* Re: [PATCH] KEYS: trusted: Use get_random-fallback for TPM
From: James Bottomley @ 2025-12-14 22:18 UTC (permalink / raw)
To: Jarkko Sakkinen, linux-integrity
Cc: David Howells, Paul Moore, James Morris, Serge E. Hallyn,
Mimi Zohar, open list:KEYS/KEYRINGS, open list:SECURITY SUBSYSTEM,
open list
In-Reply-To: <20251214213236.339586-1-jarkko@kernel.org>
On Sun, 2025-12-14 at 23:32 +0200, Jarkko Sakkinen wrote:
> 1. tpm2_get_random() is costly when TCG_TPM2_HMAC is enabled and thus
> its
> use should be pooled rather than directly used. This both reduces
> latency and improves its predictability.
>
> 2. Linux is better off overall if every subsystem uses the same
> source for
> the random bistream as the de-facto choice, unless *force majeure*
> reasons point to some other direction.
>
> In the case, of TPM there is no reason for trusted keys to invoke TPM
> directly.
That assertion isn't correct: you seem to have forgotten we had this
argument six or seven years ago, but even that was a reprise of an even
earlier one. Lore doesn't go back far enough for the intermediate one
on the tpm list, but the original was cc'd to lkml:
https://lore.kernel.org/all/1378920168.26698.64.camel@localhost/
The decision then was to use the same random source as the key
protection. Unfortunately most of the active participants have moved
on from IBM and I don't have their current email addresses, but the
bottom line is there were good reasons to do trusted keys this way that
your assertions above don't overcome. I'm not saying we shouldn't
reconsider the situation, but we need a reasoned debate rather than
simply doing it by fiat.
Regards,
James
^ permalink raw reply
* Re: [PATCH] KEYS: trusted: Use get_random-fallback for TPM
From: Jarkko Sakkinen @ 2025-12-14 21:35 UTC (permalink / raw)
To: linux-integrity
Cc: David Howells, Paul Moore, James Morris, Serge E. Hallyn,
James Bottomley, Mimi Zohar, open list:KEYS/KEYRINGS,
open list:SECURITY SUBSYSTEM, open list, David S. Miller,
Herbert Xu
In-Reply-To: <20251214213236.339586-1-jarkko@kernel.org>
On Sun, Dec 14, 2025 at 11:32:36PM +0200, Jarkko Sakkinen wrote:
> 1. tpm2_get_random() is costly when TCG_TPM2_HMAC is enabled and thus its
> use should be pooled rather than directly used. This both reduces
> latency and improves its predictability.
>
> 2. Linux is better off overall if every subsystem uses the same source for
> the random bistream as the de-facto choice, unless *force majeure*
> reasons point to some other direction.
>
> In the case, of TPM there is no reason for trusted keys to invoke TPM
> directly.
>
> Thus, unset '.get_random', which causes fallback to kernel_get_random().
>
> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
> ---
> security/keys/trusted-keys/trusted_tpm1.c | 6 ------
> 1 file changed, 6 deletions(-)
>
> diff --git a/security/keys/trusted-keys/trusted_tpm1.c b/security/keys/trusted-keys/trusted_tpm1.c
> index 636acb66a4f6..33b7739741c3 100644
> --- a/security/keys/trusted-keys/trusted_tpm1.c
> +++ b/security/keys/trusted-keys/trusted_tpm1.c
> @@ -936,11 +936,6 @@ static int trusted_tpm_unseal(struct trusted_key_payload *p, char *datablob)
> return ret;
> }
>
> -static int trusted_tpm_get_random(unsigned char *key, size_t key_len)
> -{
> - return tpm_get_random(chip, key, key_len);
> -}
> -
> static int __init init_digests(void)
> {
> int i;
> @@ -992,6 +987,5 @@ struct trusted_key_ops trusted_key_tpm_ops = {
> .init = trusted_tpm_init,
> .seal = trusted_tpm_seal,
> .unseal = trusted_tpm_unseal,
> - .get_random = trusted_tpm_get_random,
> .exit = trusted_tpm_exit,
> };
> --
> 2.39.5
>
Additional cc's as this indirectly relates to hwrng.
BR, Jarkko
^ permalink raw reply
* [PATCH] KEYS: trusted: Use get_random-fallback for TPM
From: Jarkko Sakkinen @ 2025-12-14 21:32 UTC (permalink / raw)
To: linux-integrity
Cc: Jarkko Sakkinen, David Howells, Paul Moore, James Morris,
Serge E. Hallyn, James Bottomley, Mimi Zohar,
open list:KEYS/KEYRINGS, open list:SECURITY SUBSYSTEM, open list
1. tpm2_get_random() is costly when TCG_TPM2_HMAC is enabled and thus its
use should be pooled rather than directly used. This both reduces
latency and improves its predictability.
2. Linux is better off overall if every subsystem uses the same source for
the random bistream as the de-facto choice, unless *force majeure*
reasons point to some other direction.
In the case, of TPM there is no reason for trusted keys to invoke TPM
directly.
Thus, unset '.get_random', which causes fallback to kernel_get_random().
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
security/keys/trusted-keys/trusted_tpm1.c | 6 ------
1 file changed, 6 deletions(-)
diff --git a/security/keys/trusted-keys/trusted_tpm1.c b/security/keys/trusted-keys/trusted_tpm1.c
index 636acb66a4f6..33b7739741c3 100644
--- a/security/keys/trusted-keys/trusted_tpm1.c
+++ b/security/keys/trusted-keys/trusted_tpm1.c
@@ -936,11 +936,6 @@ static int trusted_tpm_unseal(struct trusted_key_payload *p, char *datablob)
return ret;
}
-static int trusted_tpm_get_random(unsigned char *key, size_t key_len)
-{
- return tpm_get_random(chip, key, key_len);
-}
-
static int __init init_digests(void)
{
int i;
@@ -992,6 +987,5 @@ struct trusted_key_ops trusted_key_tpm_ops = {
.init = trusted_tpm_init,
.seal = trusted_tpm_seal,
.unseal = trusted_tpm_unseal,
- .get_random = trusted_tpm_get_random,
.exit = trusted_tpm_exit,
};
--
2.39.5
^ permalink raw reply related
* [PATCH] lsm: fix kernel-doc struct member names
From: Randy Dunlap @ 2025-12-14 20:15 UTC (permalink / raw)
To: linux-kernel
Cc: Randy Dunlap, Paul Moore, James Morris, Serge E. Hallyn,
linux-security-module
Use the correct struct member names to avoid kernel-doc warnings:
Warning: include/linux/lsm_hooks.h:83 struct member 'name' not described
in 'lsm_id'
Warning: include/linux/lsm_hooks.h:183 struct member 'initcall_device' not
described in 'lsm_info'
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
---
Cc: Paul Moore <paul@paul-moore.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: linux-security-module@vger.kernel.org
---
include/linux/lsm_hooks.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- linux-next-20251201.orig/include/linux/lsm_hooks.h
+++ linux-next-20251201/include/linux/lsm_hooks.h
@@ -73,7 +73,7 @@ struct lsm_static_calls_table {
/**
* struct lsm_id - Identify a Linux Security Module.
- * @lsm: name of the LSM, must be approved by the LSM maintainers
+ * @name: name of the LSM, must be approved by the LSM maintainers
* @id: LSM ID number from uapi/linux/lsm.h
*
* Contains the information that identifies the LSM.
@@ -164,7 +164,7 @@ enum lsm_order {
* @initcall_core: LSM callback for core_initcall() setup, optional
* @initcall_subsys: LSM callback for subsys_initcall() setup, optional
* @initcall_fs: LSM callback for fs_initcall setup, optional
- * @nitcall_device: LSM callback for device_initcall() setup, optional
+ * @initcall_device: LSM callback for device_initcall() setup, optional
* @initcall_late: LSM callback for late_initcall() setup, optional
*/
struct lsm_info {
^ permalink raw reply
* Re: [PATCH] host/roots: Sandbox xdg-desktop-portal-spectrum-host
From: Mickaël Salaün @ 2025-12-14 19:50 UTC (permalink / raw)
To: Demi Marie Obenour
Cc: Alyssa Ross, Spectrum OS Development, linux-security-module,
landlock, Ryan B. Sullivan, Günther Noack
In-Reply-To: <515ff0f4-2ab3-46de-8d1e-5c66a93c6ede@gmail.com>
On Sat, Dec 13, 2025 at 11:49:11PM -0500, Demi Marie Obenour wrote:
> On 12/13/25 20:39, Alyssa Ross wrote:
> > Demi Marie Obenour <demiobenour@gmail.com> writes:
> >
> >> On 12/13/25 16:42, Alyssa Ross wrote:
> >>> Demi Marie Obenour <demiobenour@gmail.com> writes:
> >>>
> >>>> On 12/13/25 14:12, Alyssa Ross wrote:
> >>>>> Demi Marie Obenour <demiobenour@gmail.com> writes:
> >>>>>
> >>>>>> It is quite possible that these Landlock rules are unnecessarily
> >>>>>> permissive, but all of the paths to which read and execute access is
> >>>>>> granted are part of the root filesystem and therefore assumed to be
> >>>>>> public knowledge. Removing access from any of them would only increase
> >>>>>> the risk of accidental breakage in the future, and would not provide any
> >>>>>> security improvements. seccomp *could* provide some improvements, but
> >>>>>> the effort needed is too high for now.
> >>>>>>
> >>>>>> Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com>
> >>>>>> ---
> >>>>>> .../template/data/service/xdg-desktop-portal-spectrum-host/run | 8 ++++++++
> >>>>>> 1 file changed, 8 insertions(+)
> >>>>>
> >>>>> Are you sure this is working as intended? There's no rule allowing
> >>>>> access to Cloud Hypervisor's VSOCK socket, and yet it still seems to be
> >>>>> able to access that. Don't you need to set a rule that *restricts*
> >>>>> filesystem access and then add holes? Did you ever see this deny
> >>>>> anything?
> >>>>
> >>>> 'man 1 setpriv' states that '--landlock-access fs' blocks all
> >>>> filesystem access unless a subsequent --landlock-rule permits it.
> >>>> I tried running with no --landlock-rule flags and the execve of
> >>>> xdg-desktop-portal-spectrum-host failed as expected.
> >>>>
> >>>> The socket is passed over stdin, and I'm pretty sure Landlock
> >>>> doesn't restrict using an already-open file descriptor.
> >>>> xdg-desktop-portal-spectrum-host does need to find the path to the
> >>>> socket, but I don't think it ever accesses that path.
> >>>
> >>> I've been looking into this a bit myself, and from what I can tell
> >>> Landlock just doesn't restrict connecting to sockets at all, even if
> >>> they're inside directories that would otherwise be inaccessible. It's
> >>> able to connect to both Cloud Hypervisor's VSOCK socket and the D-Bus
> >>> socket even with a maximally restrictive landlock rule. So you were
> >>> right after all, sorry!
> >>
> >> That's not good at all! It's a trivial sandbox escape in so many cases.
> >> For instance, with access to D-Bus I can just call `systemd-run`.
> >>
> >> I'm CCing the Landlock and LSM mailing lists because if you are
> >> correct, then this is a bad security hole.
> >
> > I don't find it that surprising given the way landlock works. "connect"
> > (to a non-abstract AF_UNIX socket) is not an operation there's a
> > landlock action for, and it's not like the other actions care about
> > access to parent directories and the like — I was able to execute a
> > program via a symlink after only giving access to the symlink's target,
> > without any access to the directory containing the symlink or the
> > symlink itself, for example. Landlock, as I understand it, is intended
> > to block a specified set of operations (on particular file hierarchies),
> > rather than to completely prevent access to those hierarchies like
> > permissions or mount namespaces could, so the lack of a way to block
> > connecting to a socket is more of a missing feature than a security
> > hole.
>
> 'man 7 unix' states:
>
> On Linux, connecting to a stream socket object requires write
> permission on that socket; sending a datagram to a datagram socket
> likewise requires write permission on that socket.
>
> Landlock is definitely being inconsistent with DAC here. Also, this
> allows real-world sandbox breakouts. On systemd systems, the simplest
> way to escape is to use systemd-run to execute arbitrary commands.
The Linux kernel is complex and the link between the VFS and named UNIX
sockets is "special" (see the linked GitHub issue). Landlock doesn't
handle named UNIX sockets yet for the same reason it doesn't handle some
other kind of kernel resources or access rights: someone needs to
implement it (including tests, doc...). There is definitely interest to
add this feature, it has been discussed for some time, but it's not
trivial. It is a work in progress though:
https://github.com/landlock-lsm/linux/issues/36
Contributions are welcome!
Regards,
Mickaël
^ permalink raw reply
* [PATCH v5 6/6] landlock: Add documentation for LANDLOCK_ADD_RULE_NO_INHERIT
From: Justin Suess @ 2025-12-14 17:05 UTC (permalink / raw)
To: Mickaël Salaün
Cc: Tingmao Wang, Günther Noack, Justin Suess, Jan Kara,
Abhinav Saxena, linux-security-module
In-Reply-To: <20251214170548.408142-1-utilityemal77@gmail.com>
Adds documentation of the flag to the userspace api, describing
the functionality of the flag and parent directory protections.
Signed-off-by: Justin Suess <utilityemal77@gmail.com>
---
v1..v5 changes:
* Initial addition
Documentation/userspace-api/landlock.rst | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/Documentation/userspace-api/landlock.rst b/Documentation/userspace-api/landlock.rst
index 1d0c2c15c22e..3671cd90fbe2 100644
--- a/Documentation/userspace-api/landlock.rst
+++ b/Documentation/userspace-api/landlock.rst
@@ -604,6 +604,23 @@ Landlock audit events with the ``LANDLOCK_RESTRICT_SELF_LOG_SAME_EXEC_OFF``,
sys_landlock_restrict_self(). See Documentation/admin-guide/LSM/landlock.rst
for more details on audit.
+Filesystem inheritance suppression (ABI < 8)
+-----------------
+
+Starting with the Landlock ABI version 8, it is possible to prevent a directory
+or file from inheriting it's parent's access grants by using the
+``LANDLOCK_ADD_RULE_NO_INHERIT`` flag passed to sys_landlock_add_rule(). This
+can be useful for policies where a parent directory needs broader access than its
+children.
+
+To mitigate sandbox-restart attacks, the inode itself, and ancestors of inodes
+tagged with ``LANDLOCK_ADD_RULE_NO_INHERIT`` cannot be removed, renamed,
+reparented, or linked into/from other directories.
+
+These parent directory protections propagate up to the root. Further inheritance
+for grants originating beneath a ``LANDLOCK_ADD_RULE_NO_INHERIT`` tagged inode
+are not affected unless also tagged with this flag.
+
.. _kernel_support:
Kernel support
--
2.51.0
^ permalink raw reply related
* [PATCH v5 5/6] landlock: Implement KUnit test for LANDLOCK_ADD_RULE_NO_INHERIT
From: Justin Suess @ 2025-12-14 17:05 UTC (permalink / raw)
To: Mickaël Salaün
Cc: Tingmao Wang, Günther Noack, Justin Suess, Jan Kara,
Abhinav Saxena, linux-security-module
In-Reply-To: <20251214170548.408142-1-utilityemal77@gmail.com>
Add a unit test for rule_flag collection, ensuring that access masks
are properly propagated with the flags.
Signed-off-by: Justin Suess <utilityemal77@gmail.com>
---
v4..v5 changes:
* None
v2..v3 changes:
* Removing erroneously misplaced code and placed in the proper
patch.
security/landlock/ruleset.c | 89 +++++++++++++++++++++++++++++++++++++
1 file changed, 89 insertions(+)
diff --git a/security/landlock/ruleset.c b/security/landlock/ruleset.c
index 9152a939d79a..8064139fde8f 100644
--- a/security/landlock/ruleset.c
+++ b/security/landlock/ruleset.c
@@ -22,6 +22,7 @@
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <uapi/linux/landlock.h>
+#include <kunit/test.h>
#include "access.h"
#include "audit.h"
@@ -770,3 +771,91 @@ landlock_init_layer_masks(const struct landlock_ruleset *const domain,
}
return handled_accesses;
}
+
+#ifdef CONFIG_SECURITY_LANDLOCK_KUNIT_TEST
+
+/**
+ * test_unmask_layers_no_inherit - Test landlock_unmask_layers() with no_inherit
+ * @test: The KUnit test context.
+ */
+static void test_unmask_layers_no_inherit(struct kunit *const test)
+{
+ struct landlock_rule *rule;
+ layer_mask_t layer_masks[LANDLOCK_NUM_ACCESS_FS];
+ struct collected_rule_flags rule_flags;
+ const access_mask_t access_request = BIT_ULL(0) | BIT_ULL(1);
+ const layer_mask_t layers_initialized = BIT_ULL(0) | BIT_ULL(1);
+ size_t i;
+
+ rule = kzalloc(struct_size(rule, layers, 2), GFP_KERNEL);
+ KUNIT_ASSERT_NOT_NULL(test, rule);
+
+ rule->num_layers = 2;
+
+ /* Layer 1: allows access 0, no_inherit */
+ rule->layers[0].level = 1;
+ rule->layers[0].access = BIT_ULL(0);
+ rule->layers[0].flags.no_inherit = 1;
+
+ /* Layer 2: allows access 1 */
+ rule->layers[1].level = 2;
+ rule->layers[1].access = BIT_ULL(1);
+
+ /* Case 1: No rule_flags provided (should behave normally) */
+ for (i = 0; i < ARRAY_SIZE(layer_masks); i++)
+ layer_masks[i] = layers_initialized;
+
+ landlock_unmask_layers(rule, access_request, &layer_masks,
+ ARRAY_SIZE(layer_masks), NULL);
+
+ /* Access 0 should be unmasked by layer 1 */
+ KUNIT_EXPECT_EQ(test, layer_masks[0], layers_initialized & ~BIT_ULL(0));
+ /* Access 1 should be unmasked by layer 2 */
+ KUNIT_EXPECT_EQ(test, layer_masks[1], layers_initialized & ~BIT_ULL(1));
+
+ /* Case 2: rule_flags provided, no existing no_inherit_masks */
+ for (i = 0; i < ARRAY_SIZE(layer_masks); i++)
+ layer_masks[i] = layers_initialized;
+ memset(&rule_flags, 0, sizeof(rule_flags));
+
+ landlock_unmask_layers(rule, access_request, &layer_masks,
+ ARRAY_SIZE(layer_masks), &rule_flags);
+
+ /* Access 0 should be unmasked by layer 1 */
+ KUNIT_EXPECT_EQ(test, layer_masks[0], layers_initialized & ~BIT_ULL(0));
+ /* Access 1 should be unmasked by layer 2 */
+ KUNIT_EXPECT_EQ(test, layer_masks[1], layers_initialized & ~BIT_ULL(1));
+
+ /* rule_flags should collect no_inherit from layer 1 */
+ KUNIT_EXPECT_EQ(test, rule_flags.no_inherit_masks, (layer_mask_t)BIT_ULL(0));
+
+ /* Case 3: rule_flags provided, layer 1 is masked by no_inherit_masks */
+ for (i = 0; i < ARRAY_SIZE(layer_masks); i++)
+ layer_masks[i] = layers_initialized;
+ memset(&rule_flags, 0, sizeof(rule_flags));
+ rule_flags.no_inherit_masks = BIT_ULL(0); /* Mask layer 1 */
+
+ landlock_unmask_layers(rule, access_request, &layer_masks,
+ ARRAY_SIZE(layer_masks), &rule_flags);
+
+ /* Access 0 should NOT be unmasked by layer 1 because it is skipped */
+ KUNIT_EXPECT_EQ(test, layer_masks[0], layers_initialized);
+ /* Access 1 should be unmasked by layer 2 */
+ KUNIT_EXPECT_EQ(test, layer_masks[1], layers_initialized & ~BIT_ULL(1));
+
+ kfree(rule);
+}
+
+static struct kunit_case ruleset_test_cases[] = {
+ KUNIT_CASE(test_unmask_layers_no_inherit),
+ {}
+};
+
+static struct kunit_suite ruleset_test_suite = {
+ .name = "landlock_ruleset",
+ .test_cases = ruleset_test_cases,
+};
+
+kunit_test_suite(ruleset_test_suite);
+
+#endif /* CONFIG_SECURITY_LANDLOCK_KUNIT_TEST */
--
2.51.0
^ permalink raw reply related
* [PATCH v5 4/6] selftests/landlock: Implement selftests for LANDLOCK_ADD_RULE_NO_INHERIT
From: Justin Suess @ 2025-12-14 17:05 UTC (permalink / raw)
To: Mickaël Salaün
Cc: Tingmao Wang, Günther Noack, Justin Suess, Jan Kara,
Abhinav Saxena, linux-security-module
In-Reply-To: <20251214170548.408142-1-utilityemal77@gmail.com>
Implements 15 selftests for the flag, covering allowed and disallowed
operations on parent and child directories when this flag is set, as
well as multi-layer configurations and flag inheritance / audit
logging. Also tests a bind mount configuration.
Signed-off-by: Justin Suess <utilityemal77@gmail.com>
---
v4..v5 changes:
* Fixed a bug in a test applying invalid access rights
to a file.
v3..v4 changes:
* Added 4 new tests for bind mount handling, increasing selftests
from 11 -> 15.
v2..v3 changes:
* Also covers flag inheritance, audit logging and
LANDLOCK_ADD_RULE_QUIET suppression.
* Increases number of selftests from 5 -> 11.
tools/testing/selftests/landlock/fs_test.c | 730 +++++++++++++++++++++
1 file changed, 730 insertions(+)
diff --git a/tools/testing/selftests/landlock/fs_test.c b/tools/testing/selftests/landlock/fs_test.c
index 44e131957fba..211c3b206710 100644
--- a/tools/testing/selftests/landlock/fs_test.c
+++ b/tools/testing/selftests/landlock/fs_test.c
@@ -1484,6 +1484,111 @@ TEST_F_FORK(layout1, inherit_superset)
ASSERT_EQ(0, test_open(file1_s1d3, O_RDONLY));
}
+TEST_F_FORK(layout1, inherit_no_inherit_flag)
+{
+ struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_fs = ACCESS_RW,
+ };
+ int ruleset_fd;
+
+ ruleset_fd =
+ landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+ ASSERT_LE(0, ruleset_fd);
+
+ add_path_beneath(_metadata, ruleset_fd, ACCESS_RW, dir_s1d1, 0);
+ add_path_beneath(_metadata, ruleset_fd, ACCESS_RO, dir_s1d2,
+ LANDLOCK_ADD_RULE_NO_INHERIT);
+
+ enforce_ruleset(_metadata, ruleset_fd);
+ ASSERT_EQ(0, close(ruleset_fd));
+
+ /* Parent directory still grants write access to its direct children. */
+ EXPECT_EQ(0, test_open(dir_s1d1, O_RDONLY | O_DIRECTORY));
+ EXPECT_EQ(0, test_open(file1_s1d1, O_WRONLY));
+
+ /* dir_s1d2 gets only its explicit read-only access rights. */
+ EXPECT_EQ(0, test_open(dir_s1d2, O_RDONLY | O_DIRECTORY));
+ EXPECT_EQ(0, test_open(file1_s1d2, O_RDONLY));
+ EXPECT_EQ(EACCES, test_open(file1_s1d2, O_WRONLY));
+
+ /* Descendants of dir_s1d2 inherit the reduced access mask. */
+ EXPECT_EQ(0, test_open(dir_s1d3, O_RDONLY | O_DIRECTORY));
+ EXPECT_EQ(0, test_open(file1_s1d3, O_RDONLY));
+ EXPECT_EQ(EACCES, test_open(file1_s1d3, O_WRONLY));
+}
+
+TEST_F_FORK(layout1, inherit_no_inherit_nested_levels)
+{
+ int ruleset_fd;
+ struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_fs = ACCESS_RW | LANDLOCK_ACCESS_FS_REFER |
+ LANDLOCK_ACCESS_FS_REMOVE_FILE |
+ LANDLOCK_ACCESS_FS_REMOVE_DIR,
+ };
+
+ ruleset_fd =
+ landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+ ASSERT_LE(0, ruleset_fd);
+
+ /* Level 1: s1d1 (RW + REFER + REMOVE + NO_INHERIT) */
+ add_path_beneath(_metadata, ruleset_fd,
+ ACCESS_RW | LANDLOCK_ACCESS_FS_REFER |
+ LANDLOCK_ACCESS_FS_REMOVE_FILE |
+ LANDLOCK_ACCESS_FS_REMOVE_DIR,
+ dir_s1d1, LANDLOCK_ADD_RULE_NO_INHERIT);
+
+ /* Level 2: s1d2 (RO + NO_INHERIT) */
+ add_path_beneath(_metadata, ruleset_fd, ACCESS_RO, dir_s1d2,
+ LANDLOCK_ADD_RULE_NO_INHERIT);
+
+ /* Level 3: s1d3 (RW + REFER + REMOVE + NO_INHERIT) */
+ add_path_beneath(_metadata, ruleset_fd,
+ ACCESS_RW | LANDLOCK_ACCESS_FS_REFER |
+ LANDLOCK_ACCESS_FS_REMOVE_FILE |
+ LANDLOCK_ACCESS_FS_REMOVE_DIR,
+ dir_s1d3, LANDLOCK_ADD_RULE_NO_INHERIT);
+
+ enforce_ruleset(_metadata, ruleset_fd);
+ ASSERT_EQ(0, close(ruleset_fd));
+
+ /*
+ * Level 3: s1d3
+ * - RW allowed (unlink file)
+ * - REFER allowed (rename file)
+ * - REMOVE_DIR denied (parent s1d2 is part of direct parent tree)
+ */
+ ASSERT_EQ(0, unlink(file1_s1d3));
+ ASSERT_EQ(0, rename(file2_s1d3, file1_s1d3));
+ ASSERT_EQ(0, rename(file1_s1d3, file2_s1d3));
+ ASSERT_EQ(-1, rmdir(dir_s1d3));
+ ASSERT_EQ(EACCES, errno);
+
+ /*
+ * Level 2: s1d2
+ * - RW denied (unlink file), layer is RO
+ * - REFER denied (rename file)
+ * - REMOVE_DIR of s1d2 not allowed (parent s1d1 is part of direct parent tree)
+ */
+ ASSERT_EQ(-1, unlink(file1_s1d2));
+ ASSERT_EQ(EACCES, errno);
+ ASSERT_EQ(-1, rename(file2_s1d2, file1_s1d2));
+ ASSERT_EQ(EACCES, errno);
+ ASSERT_EQ(-1, rmdir(dir_s1d2));
+ ASSERT_EQ(EACCES, errno);
+
+ /*
+ * Level 1: s1d1
+ * - RW allowed
+ * - Rename allowed (except for direct parent tree s1d2)
+ * - REMOVE_DIR denied (parent tmp is denied)
+ */
+ ASSERT_EQ(0, unlink(file1_s1d1));
+ ASSERT_EQ(0, rename(file2_s1d1, file1_s1d1));
+ ASSERT_EQ(0, rename(file1_s1d1, file2_s1d1));
+ ASSERT_EQ(-1, rmdir(dir_s1d1));
+ ASSERT_EQ(EACCES, errno);
+}
+
TEST_F_FORK(layout0, max_layers)
{
int i, err;
@@ -4408,6 +4513,266 @@ TEST_F_FORK(layout1, named_unix_domain_socket_ioctl)
ASSERT_EQ(0, close(cli_fd));
}
+TEST_F_FORK(layout1, inherit_no_inherit_topology_dir)
+{
+ const struct rule rules[] = {
+ {
+ .path = TMP_DIR,
+ .access = ACCESS_RW | LANDLOCK_ACCESS_FS_REMOVE_FILE,
+ },
+ {},
+ };
+ int ruleset_fd;
+
+ ruleset_fd = create_ruleset(_metadata,
+ ACCESS_RW | LANDLOCK_ACCESS_FS_REMOVE_FILE,
+ rules);
+ ASSERT_LE(0, ruleset_fd);
+
+ /* Adds a no-inherit rule on a leaf directory. */
+ add_path_beneath(_metadata, ruleset_fd, ACCESS_RO, dir_s1d3,
+ LANDLOCK_ADD_RULE_NO_INHERIT);
+
+ enforce_ruleset(_metadata, ruleset_fd);
+ ASSERT_EQ(0, close(ruleset_fd));
+
+ /*
+ * Topology modifications of the rule path and its parents are denied.
+ */
+
+ /* Target directory s1d3 */
+ ASSERT_EQ(-1, rmdir(dir_s1d3));
+ ASSERT_EQ(EACCES, errno);
+ ASSERT_EQ(-1, rename(dir_s1d3, dir_s2d3));
+ ASSERT_EQ(EACCES, errno);
+
+ /* Parent directory s1d2 */
+ ASSERT_EQ(-1, rmdir(dir_s1d2));
+ ASSERT_EQ(EACCES, errno);
+ ASSERT_EQ(-1, rename(dir_s1d2, dir_s2d2));
+ ASSERT_EQ(EACCES, errno);
+
+ /* Grandparent directory s1d1 */
+ ASSERT_EQ(-1, rmdir(dir_s1d1));
+ ASSERT_EQ(EACCES, errno);
+ ASSERT_EQ(-1, rename(dir_s1d1, dir_s2d1));
+ ASSERT_EQ(EACCES, errno);
+
+ /*
+ * Sibling operations are allowed.
+ */
+ /* Sibling of s1d3 */
+ ASSERT_EQ(0, unlink(file1_s1d2));
+ /* Sibling of s1d2 */
+ ASSERT_EQ(0, unlink(file1_s1d1));
+
+ /*
+ * Content of the no-inherit directory is restricted by the rule (RO).
+ */
+ ASSERT_EQ(-1, unlink(file1_s1d3));
+ ASSERT_EQ(EACCES, errno);
+}
+
+TEST_F_FORK(layout1, no_inherit_allow_inner_removal)
+{
+ int ruleset_fd;
+ struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_fs = ACCESS_RW | LANDLOCK_ACCESS_FS_REMOVE_FILE,
+ };
+
+ ruleset_fd =
+ landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+ ASSERT_LE(0, ruleset_fd);
+
+ add_path_beneath(_metadata, ruleset_fd,
+ ACCESS_RW | LANDLOCK_ACCESS_FS_REMOVE_FILE, dir_s1d2,
+ LANDLOCK_ADD_RULE_NO_INHERIT);
+
+ enforce_ruleset(_metadata, ruleset_fd);
+ ASSERT_EQ(0, close(ruleset_fd));
+
+ /*
+ * Content of the no-inherit directory is mutable (RW).
+ * This checks that the no-inherit flag does not seal the content.
+ */
+ ASSERT_EQ(0, unlink(file1_s1d2));
+
+ /*
+ * Topology modifications of the rule path are denied.
+ */
+ ASSERT_EQ(-1, rmdir(dir_s1d2));
+ ASSERT_EQ(EACCES, errno);
+ ASSERT_EQ(-1, rename(dir_s1d2, dir_s2d2));
+ ASSERT_EQ(EACCES, errno);
+}
+
+TEST_F_FORK(layout1, inherit_no_inherit_topology_unrelated)
+{
+ const struct rule rules[] = {
+ {
+ .path = TMP_DIR,
+ .access = ACCESS_RW,
+ },
+ {},
+ };
+ static const char unrelated_dir[] = TMP_DIR "/s2d1/unrelated";
+ static const char unrelated_file[] = TMP_DIR "/s2d1/unrelated/f1";
+ int ruleset_fd;
+
+ ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
+ ASSERT_LE(0, ruleset_fd);
+
+ /* Adds a no-inherit rule on a leaf directory unrelated to s2. */
+ add_path_beneath(_metadata, ruleset_fd, ACCESS_RO, dir_s1d3,
+ LANDLOCK_ADD_RULE_NO_INHERIT);
+
+ enforce_ruleset(_metadata, ruleset_fd);
+ ASSERT_EQ(0, close(ruleset_fd));
+
+ /* Ensure we can still create and delete files outside the sealed branch. */
+ ASSERT_EQ(0, mkdir(unrelated_dir, 0700));
+ ASSERT_EQ(0, mknod(unrelated_file, S_IFREG | 0600, 0));
+ ASSERT_EQ(0, unlink(unrelated_file));
+ ASSERT_EQ(0, rmdir(unrelated_dir));
+
+ /* Existing siblings in s2 remain modifiable. */
+ ASSERT_EQ(0, unlink(file1_s2d1));
+ ASSERT_EQ(0, mknod(file1_s2d1, S_IFREG | 0700, 0));
+}
+
+TEST_F_FORK(layout1, inherit_no_inherit_descendant_rw)
+{
+ const struct rule rules[] = {
+ {
+ .path = TMP_DIR,
+ .access = ACCESS_RO,
+ },
+ {},
+ };
+ const __u64 handled_access = ACCESS_RW | LANDLOCK_ACCESS_FS_MAKE_REG |
+ LANDLOCK_ACCESS_FS_REMOVE_FILE;
+ static const char child_file[] =
+ TMP_DIR "/s1d1/s1d2/s1d3/rw_descendant";
+ int ruleset_fd;
+
+ ruleset_fd = create_ruleset(_metadata, handled_access, rules);
+ ASSERT_LE(0, ruleset_fd);
+
+ add_path_beneath(_metadata, ruleset_fd, ACCESS_RO, dir_s1d2,
+ LANDLOCK_ADD_RULE_NO_INHERIT);
+ add_path_beneath(_metadata, ruleset_fd,
+ ACCESS_RW | LANDLOCK_ACCESS_FS_MAKE_REG |
+ LANDLOCK_ACCESS_FS_REMOVE_FILE,
+ dir_s1d3, 0);
+
+ enforce_ruleset(_metadata, ruleset_fd);
+ ASSERT_EQ(0, close(ruleset_fd));
+
+ ASSERT_EQ(0, mknod(child_file, S_IFREG | 0600, 0));
+ ASSERT_EQ(0, unlink(child_file));
+}
+
+TEST_F_FORK(layout1, inherit_no_inherit_topology_file)
+{
+ const struct rule rules[] = {
+ {
+ .path = TMP_DIR,
+ .access = ACCESS_RW,
+ },
+ {},
+ };
+ int ruleset_fd;
+
+ /*
+ * Both file1_s1d2 and file2_s1d2 already exist from the fixture.
+ * file2_s1d2 is in the same directory as file1_s1d2 and will be
+ * used to test inheritance vs. NO_INHERIT behavior.
+ */
+
+ ruleset_fd = create_ruleset(_metadata, ACCESS_RW, rules);
+ ASSERT_LE(0, ruleset_fd);
+
+ /*
+ * Add a NO_INHERIT rule on file1_s1d2 with READ_FILE access.
+ * This should succeed (files can have NO_INHERIT).
+ * Use READ_FILE (not ACCESS_RO which includes READ_DIR) since
+ * directory access rights don't make sense for files.
+ */
+ add_path_beneath(_metadata, ruleset_fd, LANDLOCK_ACCESS_FS_READ_FILE,
+ file1_s1d2, LANDLOCK_ADD_RULE_NO_INHERIT);
+
+ enforce_ruleset(_metadata, ruleset_fd);
+ ASSERT_EQ(0, close(ruleset_fd));
+
+ /*
+ * file1_s1d2 has NO_INHERIT with READ_FILE access only,
+ * so it should only be readable (not inheriting RW from parent TMP_DIR).
+ */
+ ASSERT_EQ(0, test_open(file1_s1d2, O_RDONLY));
+ ASSERT_EQ(EACCES, test_open(file1_s1d2, O_WRONLY));
+
+ /*
+ * file2_s1d2 does not have NO_INHERIT, so it should inherit
+ * RW access from parent TMP_DIR rule.
+ */
+ ASSERT_EQ(0, test_open(file2_s1d2, O_RDONLY));
+ ASSERT_EQ(0, test_open(file2_s1d2, O_WRONLY));
+}
+
+TEST_F_FORK(layout1, inherit_no_inherit_layered)
+{
+ const struct rule layer1_and_2[] = {
+ {
+ .path = TMP_DIR,
+ .access = ACCESS_RW | LANDLOCK_ACCESS_FS_REMOVE_FILE,
+ },
+ {},
+ };
+ int ruleset_fd;
+ static const char unrelated_dir[] = TMP_DIR "/s2d1/unrelated";
+ static const char unrelated_file[] = TMP_DIR "/s2d1/unrelated/f1";
+
+ /* Layer 1: RW on TMP_DIR */
+ ruleset_fd = create_ruleset(_metadata,
+ ACCESS_RW | LANDLOCK_ACCESS_FS_REMOVE_FILE,
+ layer1_and_2);
+ ASSERT_LE(0, ruleset_fd);
+ enforce_ruleset(_metadata, ruleset_fd);
+ ASSERT_EQ(0, close(ruleset_fd));
+
+ /* Layer 2: Add no-inherit RO rule on s1d2 */
+ ruleset_fd = create_ruleset(_metadata,
+ ACCESS_RW | LANDLOCK_ACCESS_FS_REMOVE_FILE,
+ layer1_and_2);
+ ASSERT_LE(0, ruleset_fd);
+ add_path_beneath(_metadata, ruleset_fd, ACCESS_RO, dir_s1d2,
+ LANDLOCK_ADD_RULE_NO_INHERIT);
+ enforce_ruleset(_metadata, ruleset_fd);
+ ASSERT_EQ(0, close(ruleset_fd));
+
+ /* Operations in unrelated areas should still work */
+ ASSERT_EQ(0, mkdir(unrelated_dir, 0700));
+ ASSERT_EQ(0, mknod(unrelated_file, S_IFREG | 0600, 0));
+ ASSERT_EQ(0, unlink(unrelated_file));
+ ASSERT_EQ(0, rmdir(unrelated_dir));
+
+ /* Creating in s1d1 should be allowed (parent still has RW) */
+ ASSERT_EQ(0, mknod(TMP_DIR "/s1d1/newfile", S_IFREG | 0600, 0));
+ ASSERT_EQ(0, unlink(TMP_DIR "/s1d1/newfile"));
+
+ /* Content of s1d2 should be read-only */
+ ASSERT_EQ(-1, unlink(file1_s1d2));
+ ASSERT_EQ(EACCES, errno);
+
+ /* Topology changes to s1d2 should be denied */
+ ASSERT_EQ(-1, rename(dir_s1d2, TMP_DIR "/s2d1/renamed"));
+ ASSERT_EQ(EACCES, errno);
+
+ /* Renaming s1d1 should also be denied (it's an ancestor) */
+ ASSERT_EQ(-1, rename(dir_s1d1, TMP_DIR "/s2d1/renamed"));
+ ASSERT_EQ(EACCES, errno);
+}
+
/* clang-format off */
FIXTURE(ioctl) {};
@@ -5747,6 +6112,277 @@ TEST_F_FORK(layout4_disconnected_leafs, read_rename_exchange)
test_renameat(s1d42_bind_fd, "f4", s1d42_bind_fd, "f5"));
}
+/*
+ * Test that LANDLOCK_ADD_RULE_NO_INHERIT on a directory accessed via a mount
+ * point protects the parent hierarchy within the mount from topology changes.
+ *
+ * Layout (after bind mount s1d2 -> s2d2):
+ * tmp
+ * ├── s1d1
+ * │ └── s1d2 [source of bind mount]
+ * │ ├── s1d31
+ * │ │ └── s1d41
+ * │ │ ├── f1
+ * │ │ └── f2
+ * │ └── s1d32
+ * │ └── s1d42
+ * │ ├── f3
+ * │ └── f4
+ * └── s2d1
+ * └── s2d2 [bind mount destination from s1d2]
+ * ├── s1d31 <- parent of protected dir, should be immovable
+ * │ └── s1d41 <- protected with NO_INHERIT
+ * │ ├── f1
+ * │ └── f2
+ * └── s1d32
+ * └── s1d42
+ * ├── f3
+ * └── f4
+ *
+ * When s1d41 (accessed via the mount at s2d2) is protected with NO_INHERIT,
+ * its parent directories within the mount (s1d31) should be immovable.
+ */
+TEST_F_FORK(layout4_disconnected_leafs, no_inherit_mount_parent_rename)
+{
+ int ruleset_fd, s1d41_bind_fd;
+ struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_fs = ACCESS_RW | LANDLOCK_ACCESS_FS_REFER |
+ LANDLOCK_ACCESS_FS_REMOVE_FILE |
+ LANDLOCK_ACCESS_FS_REMOVE_DIR,
+ };
+
+ ruleset_fd =
+ landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+ ASSERT_LE(0, ruleset_fd);
+
+ /* Allow full access to TMP_DIR. */
+ add_path_beneath(_metadata, ruleset_fd,
+ ACCESS_RW | LANDLOCK_ACCESS_FS_REFER |
+ LANDLOCK_ACCESS_FS_REMOVE_FILE |
+ LANDLOCK_ACCESS_FS_REMOVE_DIR,
+ TMP_DIR, 0);
+
+ /*
+ * Access s1d41 through the bind mount at s2d2 and protect it with
+ * NO_INHERIT. This should seal the parent hierarchy through the mount.
+ */
+ s1d41_bind_fd = open(TMP_DIR "/s2d1/s2d2/s1d31/s1d41",
+ O_DIRECTORY | O_PATH | O_CLOEXEC);
+ ASSERT_LE(0, s1d41_bind_fd);
+
+ ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
+ &(struct landlock_path_beneath_attr){
+ .parent_fd = s1d41_bind_fd,
+ .allowed_access = ACCESS_RO,
+ },
+ LANDLOCK_ADD_RULE_NO_INHERIT));
+ EXPECT_EQ(0, close(s1d41_bind_fd));
+
+ enforce_ruleset(_metadata, ruleset_fd);
+ ASSERT_EQ(0, close(ruleset_fd));
+
+ /*
+ * s1d31 is the parent of s1d41 within the mount. Renaming it should
+ * be denied because it is part of the protected parent hierarchy.
+ * Test via the mount path.
+ */
+ ASSERT_EQ(-1, rename(TMP_DIR "/s2d1/s2d2/s1d31",
+ TMP_DIR "/s2d1/s2d2/s1d31_renamed"));
+ ASSERT_EQ(EACCES, errno);
+
+ /*
+ * s1d32 is a sibling directory (not in the protected parent chain),
+ * so renaming it should be allowed.
+ */
+ ASSERT_EQ(0, rename(TMP_DIR "/s2d1/s2d2/s1d32",
+ TMP_DIR "/s2d1/s2d2/s1d32_renamed"));
+ ASSERT_EQ(0, rename(TMP_DIR "/s2d1/s2d2/s1d32_renamed",
+ TMP_DIR "/s2d1/s2d2/s1d32"));
+
+ /*
+ * Renaming directories not in the protected parent hierarchy should
+ * still be allowed.
+ */
+ ASSERT_EQ(0, rename(TMP_DIR "/s3d1", TMP_DIR "/s3d1_renamed"));
+ ASSERT_EQ(0, rename(TMP_DIR "/s3d1_renamed", TMP_DIR "/s3d1"));
+}
+
+TEST_F_FORK(layout4_disconnected_leafs, no_inherit_mount_parent_rmdir)
+{
+ int ruleset_fd, s1d41_bind_fd;
+ struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_fs = ACCESS_RW | LANDLOCK_ACCESS_FS_REFER |
+ LANDLOCK_ACCESS_FS_REMOVE_FILE |
+ LANDLOCK_ACCESS_FS_REMOVE_DIR,
+ };
+
+ ruleset_fd =
+ landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+ ASSERT_LE(0, ruleset_fd);
+
+ /* Allow full access to TMP_DIR. */
+ add_path_beneath(_metadata, ruleset_fd,
+ ACCESS_RW | LANDLOCK_ACCESS_FS_REFER |
+ LANDLOCK_ACCESS_FS_REMOVE_FILE |
+ LANDLOCK_ACCESS_FS_REMOVE_DIR,
+ TMP_DIR, 0);
+
+ /*
+ * Access s1d41 through the bind mount at s2d2 and protect it with
+ * NO_INHERIT. This should seal the parent hierarchy through the mount.
+ */
+ s1d41_bind_fd = open(TMP_DIR "/s2d1/s2d2/s1d31/s1d41",
+ O_DIRECTORY | O_PATH | O_CLOEXEC);
+ ASSERT_LE(0, s1d41_bind_fd);
+
+ ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
+ &(struct landlock_path_beneath_attr){
+ .parent_fd = s1d41_bind_fd,
+ .allowed_access = ACCESS_RO,
+ },
+ LANDLOCK_ADD_RULE_NO_INHERIT));
+ EXPECT_EQ(0, close(s1d41_bind_fd));
+
+ enforce_ruleset(_metadata, ruleset_fd);
+ ASSERT_EQ(0, close(ruleset_fd));
+
+ /*
+ * s1d31 is the parent of s1d41 within the mount. Removing it should
+ * be denied because it is part of the protected parent hierarchy.
+ */
+ ASSERT_EQ(-1, rmdir(TMP_DIR "/s2d1/s2d2/s1d31"));
+ ASSERT_EQ(EACCES, errno);
+
+ /*
+ * Removing an unrelated directory should still be allowed (if empty).
+ */
+ ASSERT_EQ(0, rmdir(TMP_DIR "/s3d1"));
+ ASSERT_EQ(0, mkdir(TMP_DIR "/s3d1", 0755));
+}
+
+TEST_F_FORK(layout4_disconnected_leafs, no_inherit_mount_parent_link)
+{
+ int ruleset_fd, s1d41_bind_fd;
+ struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_fs = ACCESS_RW | LANDLOCK_ACCESS_FS_REFER |
+ LANDLOCK_ACCESS_FS_REMOVE_FILE |
+ LANDLOCK_ACCESS_FS_REMOVE_DIR |
+ LANDLOCK_ACCESS_FS_MAKE_REG,
+ };
+
+ ruleset_fd =
+ landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+ ASSERT_LE(0, ruleset_fd);
+
+ /* Allow full access to TMP_DIR. */
+ add_path_beneath(_metadata, ruleset_fd,
+ ACCESS_RW | LANDLOCK_ACCESS_FS_REFER |
+ LANDLOCK_ACCESS_FS_REMOVE_FILE |
+ LANDLOCK_ACCESS_FS_REMOVE_DIR |
+ LANDLOCK_ACCESS_FS_MAKE_REG,
+ TMP_DIR, 0);
+
+ /*
+ * Access s1d41 through the bind mount at s2d2 and protect it with
+ * NO_INHERIT. This should seal the parent hierarchy through the mount.
+ */
+ s1d41_bind_fd = open(TMP_DIR "/s2d1/s2d2/s1d31/s1d41",
+ O_DIRECTORY | O_PATH | O_CLOEXEC);
+ ASSERT_LE(0, s1d41_bind_fd);
+
+ ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
+ &(struct landlock_path_beneath_attr){
+ .parent_fd = s1d41_bind_fd,
+ .allowed_access = ACCESS_RO,
+ },
+ LANDLOCK_ADD_RULE_NO_INHERIT));
+ EXPECT_EQ(0, close(s1d41_bind_fd));
+
+ enforce_ruleset(_metadata, ruleset_fd);
+ ASSERT_EQ(0, close(ruleset_fd));
+
+ /*
+ * Creating a hard link within the protected NO_INHERIT directory should
+ * be denied because NO_INHERIT grants only ACCESS_RO (no MAKE_REG).
+ */
+ ASSERT_EQ(-1, linkat(AT_FDCWD, TMP_DIR "/s2d1/s2d2/s1d31/s1d41/f1",
+ AT_FDCWD, TMP_DIR "/s2d1/s2d2/s1d31/s1d41/f1_link",
+ 0));
+ ASSERT_EQ(EACCES, errno);
+
+ /*
+ * Creating links within directories outside the protected chain
+ * (using the mount source path to avoid EXDEV) should still be allowed.
+ */
+ ASSERT_EQ(0, linkat(AT_FDCWD, TMP_DIR "/s1d1/s1d2/s1d32/s1d42/f3",
+ AT_FDCWD, TMP_DIR "/s1d1/s1d2/s1d32/s1d42/f3_link",
+ 0));
+ ASSERT_EQ(0, unlink(TMP_DIR "/s1d1/s1d2/s1d32/s1d42/f3_link"));
+}
+
+/*
+ * Test that NO_INHERIT protection extends to the mount source hierarchy.
+ * If a directory is protected via a mount path, its parents within the
+ * mount source should also be protected from topology changes.
+ */
+TEST_F_FORK(layout4_disconnected_leafs, no_inherit_source_parent_rename)
+{
+ int ruleset_fd, s1d41_bind_fd;
+ struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_fs = ACCESS_RW | LANDLOCK_ACCESS_FS_REFER |
+ LANDLOCK_ACCESS_FS_REMOVE_FILE |
+ LANDLOCK_ACCESS_FS_REMOVE_DIR,
+ };
+
+ ruleset_fd =
+ landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
+ ASSERT_LE(0, ruleset_fd);
+
+ /* Allow full access to TMP_DIR. */
+ add_path_beneath(_metadata, ruleset_fd,
+ ACCESS_RW | LANDLOCK_ACCESS_FS_REFER |
+ LANDLOCK_ACCESS_FS_REMOVE_FILE |
+ LANDLOCK_ACCESS_FS_REMOVE_DIR,
+ TMP_DIR, 0);
+
+ /*
+ * Access s1d41 through the bind mount at s2d2 and protect it with
+ * NO_INHERIT. The source mount path parents should also be protected.
+ */
+ s1d41_bind_fd = open(TMP_DIR "/s2d1/s2d2/s1d31/s1d41",
+ O_DIRECTORY | O_PATH | O_CLOEXEC);
+ ASSERT_LE(0, s1d41_bind_fd);
+
+ ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
+ &(struct landlock_path_beneath_attr){
+ .parent_fd = s1d41_bind_fd,
+ .allowed_access = ACCESS_RO,
+ },
+ LANDLOCK_ADD_RULE_NO_INHERIT));
+ EXPECT_EQ(0, close(s1d41_bind_fd));
+
+ enforce_ruleset(_metadata, ruleset_fd);
+ ASSERT_EQ(0, close(ruleset_fd));
+
+ /*
+ * The mount source is s1d1/s1d2. The protected directory s1d41 is at
+ * s1d1/s1d2/s1d31/s1d41. The parent s1d31 within the mount source
+ * should be protected from topology changes.
+ */
+ ASSERT_EQ(-1, rename(TMP_DIR "/s1d1/s1d2/s1d31",
+ TMP_DIR "/s1d1/s1d2/s1d31_renamed"));
+ ASSERT_EQ(EACCES, errno);
+
+ /*
+ * s1d32 is a sibling, not in the protected parent chain. It should
+ * be renamable.
+ */
+ ASSERT_EQ(0, rename(TMP_DIR "/s1d1/s1d2/s1d32",
+ TMP_DIR "/s1d1/s1d2/s1d32_renamed"));
+ ASSERT_EQ(0, rename(TMP_DIR "/s1d1/s1d2/s1d32_renamed",
+ TMP_DIR "/s1d1/s1d2/s1d32"));
+}
+
/*
* layout5_disconnected_branch before rename:
*
@@ -7231,6 +7867,100 @@ TEST_F(audit_layout1, write_file)
EXPECT_EQ(1, records.domain);
}
+TEST_F(audit_layout1, no_inherit_parent_is_logged)
+{
+ struct audit_records records;
+ struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_fs = ACCESS_RW,
+ };
+ int ruleset_fd;
+
+ ruleset_fd = landlock_create_ruleset(&ruleset_attr,
+ sizeof(ruleset_attr), 0);
+ ASSERT_LE(0, ruleset_fd);
+
+ /* Base read-only rule at s1d1. */
+ add_path_beneath(_metadata, ruleset_fd, ACCESS_RO, dir_s1d1, 0);
+ /* Descendant s1d1/s1d2/s1d3 forbids inheritance but should still log. */
+ add_path_beneath(_metadata, ruleset_fd, ACCESS_RO, dir_s1d3,
+ LANDLOCK_ADD_RULE_NO_INHERIT);
+
+ enforce_ruleset(_metadata, ruleset_fd);
+
+ EXPECT_EQ(EACCES, test_open(file1_s1d2, O_WRONLY));
+ EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd,
+ "fs\\.write_file", file1_s1d2));
+ EXPECT_EQ(0, audit_count_records(self->audit_fd, &records));
+ EXPECT_EQ(0, records.access);
+ EXPECT_EQ(1, records.domain);
+
+ EXPECT_EQ(0, close(ruleset_fd));
+}
+
+TEST_F(audit_layout1, no_inherit_blocks_quiet_flag_inheritance)
+{
+ struct audit_records records;
+ struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_fs = ACCESS_RW,
+ .quiet_access_fs = ACCESS_RW,
+ };
+ int ruleset_fd;
+
+ ruleset_fd = landlock_create_ruleset(&ruleset_attr,
+ sizeof(ruleset_attr), 0);
+ ASSERT_LE(0, ruleset_fd);
+
+ /* Base read-only rule at tmp/s1d1 with quiet flag. */
+ add_path_beneath(_metadata, ruleset_fd, ACCESS_RO, dir_s1d1,
+ LANDLOCK_ADD_RULE_QUIET);
+ /* Descendant tmp/s1d1/s1d2/s1d3 forbids inheritance of quiet flag and should still log. */
+ add_path_beneath(_metadata, ruleset_fd, ACCESS_RO, dir_s1d3,
+ LANDLOCK_ADD_RULE_NO_INHERIT);
+
+ enforce_ruleset(_metadata, ruleset_fd);
+
+ EXPECT_EQ(EACCES, test_open(file1_s1d3, O_WRONLY));
+ EXPECT_EQ(0, matches_log_fs(_metadata, self->audit_fd,
+ "fs\\.write_file", file1_s1d3));
+ EXPECT_EQ(0, audit_count_records(self->audit_fd, &records));
+ EXPECT_EQ(0, records.access);
+ EXPECT_EQ(1, records.domain);
+
+ EXPECT_EQ(0, close(ruleset_fd));
+}
+
+TEST_F(audit_layout1, no_inherit_quiet_parent)
+{
+ struct audit_records records;
+ struct landlock_ruleset_attr ruleset_attr = {
+ .handled_access_fs = ACCESS_RW,
+ .quiet_access_fs = ACCESS_RW,
+ };
+ int ruleset_fd;
+
+ ruleset_fd = landlock_create_ruleset(&ruleset_attr,
+ sizeof(ruleset_attr), 0);
+ ASSERT_LE(0, ruleset_fd);
+
+ /* Base read-only rule at tmp/s1d1 with quiet flag. */
+ add_path_beneath(_metadata, ruleset_fd, ACCESS_RO, dir_s1d1,
+ LANDLOCK_ADD_RULE_QUIET);
+ /* Access to dir_s1d1 shouldn't log */
+ add_path_beneath(_metadata, ruleset_fd, ACCESS_RO, dir_s1d3,
+ LANDLOCK_ADD_RULE_NO_INHERIT);
+
+ enforce_ruleset(_metadata, ruleset_fd);
+
+ EXPECT_EQ(EACCES, test_open(file1_s1d1, O_WRONLY));
+ EXPECT_NE(0, matches_log_fs(_metadata, self->audit_fd,
+ "fs\\.write_file", file1_s1d1));
+ EXPECT_EQ(0, audit_count_records(self->audit_fd, &records));
+ EXPECT_EQ(0, records.access);
+ EXPECT_EQ(0, records.domain);
+
+ EXPECT_EQ(0, close(ruleset_fd));
+}
+
TEST_F(audit_layout1, read_file)
{
struct audit_records records;
--
2.51.0
^ permalink raw reply related
* [PATCH v5 3/6] samples/landlock: Add LANDLOCK_ADD_RULE_NO_INHERIT to landlock-sandboxer
From: Justin Suess @ 2025-12-14 17:05 UTC (permalink / raw)
To: Mickaël Salaün
Cc: Tingmao Wang, Günther Noack, Justin Suess, Jan Kara,
Abhinav Saxena, linux-security-module
In-Reply-To: <20251214170548.408142-1-utilityemal77@gmail.com>
Adds support to landlock-sandboxer with environment variable
LL_FS_NO_INHERIT, which can be tagged on any filesystem object to
suppress access right inheritance.
Cc: Tingmao Wang <m@maowtm.org>
Signed-off-by: Justin Suess <utilityemal77@gmail.com>
---
v4..v5 changes:
* None
v3..v4 changes:
* Modified LL_FS_R(O/W)_NO_INHERIT variables to a single variable
to allow access rule combination. (credit to Tingmao Wang)
v2..v3 changes:
* Minor formatting fixes
samples/landlock/sandboxer.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/samples/landlock/sandboxer.c b/samples/landlock/sandboxer.c
index 07dc0013ff19..852ffa413c75 100644
--- a/samples/landlock/sandboxer.c
+++ b/samples/landlock/sandboxer.c
@@ -60,6 +60,7 @@ static inline int landlock_restrict_self(const int ruleset_fd,
#define ENV_FS_RW_NAME "LL_FS_RW"
#define ENV_FS_QUIET_NAME "LL_FS_QUIET"
#define ENV_FS_QUIET_ACCESS_NAME "LL_FS_QUIET_ACCESS"
+#define ENV_FS_NO_INHERIT_NAME "LL_FS_NO_INHERIT"
#define ENV_TCP_BIND_NAME "LL_TCP_BIND"
#define ENV_TCP_CONNECT_NAME "LL_TCP_CONNECT"
#define ENV_NET_QUIET_NAME "LL_NET_QUIET"
@@ -383,6 +384,7 @@ static const char help[] =
"but to test audit we can set " ENV_FORCE_LOG_NAME "=1\n"
ENV_FS_QUIET_NAME " and " ENV_NET_QUIET_NAME ", both optional, can then be used "
"to make access to some denied paths or network ports not trigger audit logging.\n"
+ ENV_FS_NO_INHERIT_NAME " can be used to suppress access right propagation (ABI >= 8).\n"
ENV_FS_QUIET_ACCESS_NAME " and " ENV_NET_QUIET_ACCESS_NAME " can be used to specify "
"which accesses should be quieted (defaults to all):\n"
"* " ENV_FS_QUIET_ACCESS_NAME ": file system accesses to quiet\n"
@@ -430,6 +432,7 @@ int main(const int argc, char *const argv[], char *const *const envp)
};
bool quiet_supported = true;
+ bool no_inherit_supported = true;
int supported_restrict_flags = LANDLOCK_RESTRICT_SELF_LOG_NEW_EXEC_ON;
int set_restrict_flags = 0;
@@ -517,8 +520,9 @@ int main(const int argc, char *const argv[], char *const *const envp)
LANDLOCK_ABI_LAST, abi);
__attribute__((fallthrough));
case 7:
- /* Don't add quiet flags for ABI < 8 later on. */
+ /* Don't add quiet/no_inherit flags for ABI < 8 later on. */
quiet_supported = false;
+ no_inherit_supported = false;
__attribute__((fallthrough));
case LANDLOCK_ABI_LAST:
@@ -605,6 +609,13 @@ int main(const int argc, char *const argv[], char *const *const envp)
goto err_close_ruleset;
}
+ /* Don't require this env to be present. */
+ if (no_inherit_supported && getenv(ENV_FS_NO_INHERIT_NAME)) {
+ if (populate_ruleset_fs(ENV_FS_NO_INHERIT_NAME, ruleset_fd, 0,
+ LANDLOCK_ADD_RULE_NO_INHERIT))
+ goto err_close_ruleset;
+ }
+
if (populate_ruleset_net(ENV_TCP_BIND_NAME, ruleset_fd,
LANDLOCK_ACCESS_NET_BIND_TCP, 0)) {
goto err_close_ruleset;
--
2.51.0
^ permalink raw reply related
* [PATCH v5 2/6] landlock: Implement LANDLOCK_ADD_RULE_NO_INHERIT userspace api
From: Justin Suess @ 2025-12-14 17:05 UTC (permalink / raw)
To: Mickaël Salaün
Cc: Tingmao Wang, Günther Noack, Justin Suess, Jan Kara,
Abhinav Saxena, linux-security-module
In-Reply-To: <20251214170548.408142-1-utilityemal77@gmail.com>
Implements the syscall side flag handling and kernel api headers for the
LANDLOCK_ADD_RULE_NO_INHERIT flag.
Signed-off-by: Justin Suess <utilityemal77@gmail.com>
---
v4..v5 changes:
* Moved syscall handling to this patch and moved out flag definition
to allow independent build.
v3..v4 changes:
* Changed documentation to reflect protections now apply to VFS root
instead of the mountpoint.
v2..v3 changes:
* Extended documentation for flag inheritance suppression on
LANDLOCK_ADD_RULE_NO_INHERIT.
* Extended the flag validation rules in the syscall.
* Added mention of no inherit in empty rules in add_rule_path_beneath
as per Tingmao Wang's suggestion.
* Added check for useless no-inherit flag in networking rules.
security/landlock/ruleset.c | 19 ++++++++++++++++++-
security/landlock/syscalls.c | 16 ++++++++++++----
2 files changed, 30 insertions(+), 5 deletions(-)
diff --git a/security/landlock/ruleset.c b/security/landlock/ruleset.c
index 750a444e1983..9152a939d79a 100644
--- a/security/landlock/ruleset.c
+++ b/security/landlock/ruleset.c
@@ -255,8 +255,13 @@ static int insert_rule(struct landlock_ruleset *const ruleset,
return -EINVAL;
if (WARN_ON_ONCE(this->layers[0].level != 0))
return -EINVAL;
+ /* Merge the flags into the rules */
this->layers[0].access |= (*layers)[0].access;
this->layers[0].flags.quiet |= (*layers)[0].flags.quiet;
+ this->layers[0].flags.no_inherit |=
+ (*layers)[0].flags.no_inherit;
+ this->layers[0].flags.has_no_inherit_descendant |=
+ (*layers)[0].flags.has_no_inherit_descendant;
return 0;
}
@@ -315,7 +320,10 @@ int landlock_insert_rule(struct landlock_ruleset *const ruleset,
.level = 0,
.flags = {
.quiet = !!(flags & LANDLOCK_ADD_RULE_QUIET),
- },
+ .no_inherit = !!(flags & LANDLOCK_ADD_RULE_NO_INHERIT),
+ .has_no_inherit_descendant =
+ !!(flags & LANDLOCK_ADD_RULE_NO_INHERIT),
+ }
} };
build_check_layer();
@@ -662,9 +670,18 @@ bool landlock_unmask_layers(const struct landlock_rule *const rule,
unsigned long access_bit;
bool is_empty;
+ /* Skip layers that already have no inherit flags. */
+ if (rule_flags &&
+ (rule_flags->no_inherit_masks & layer_bit))
+ continue;
+
/* Collect rule flags for each layer. */
if (rule_flags && layer->flags.quiet)
rule_flags->quiet_masks |= layer_bit;
+ if (rule_flags && layer->flags.no_inherit)
+ rule_flags->no_inherit_masks |= layer_bit;
+ if (rule_flags && layer->flags.has_no_inherit_descendant)
+ rule_flags->no_inherit_desc_masks |= layer_bit;
/*
* Records in @layer_masks which layer grants access to each requested
diff --git a/security/landlock/syscalls.c b/security/landlock/syscalls.c
index 5cf1183bb596..cffe7d944ae5 100644
--- a/security/landlock/syscalls.c
+++ b/security/landlock/syscalls.c
@@ -352,7 +352,7 @@ static int add_rule_path_beneath(struct landlock_ruleset *const ruleset,
/*
* Informs about useless rule: empty allowed_access (i.e. deny rules)
* are ignored in path walks. However, the rule is not useless if it
- * is there to hold a quiet flag
+ * is there to hold a quiet or no inherit flag.
*/
if (!flags && !path_beneath_attr.allowed_access)
return -ENOMSG;
@@ -407,6 +407,10 @@ static int add_rule_net_port(struct landlock_ruleset *ruleset,
if (flags & LANDLOCK_ADD_RULE_QUIET && !ruleset->quiet_masks.net)
return -EINVAL;
+ /* No inherit is always useless for this scope */
+ if (flags & LANDLOCK_ADD_RULE_NO_INHERIT)
+ return -EINVAL;
+
/* Denies inserting a rule with port greater than 65535. */
if (net_port_attr.port > U16_MAX)
return -EINVAL;
@@ -424,7 +428,7 @@ static int add_rule_net_port(struct landlock_ruleset *ruleset,
* @rule_type: Identify the structure type pointed to by @rule_attr:
* %LANDLOCK_RULE_PATH_BENEATH or %LANDLOCK_RULE_NET_PORT.
* @rule_attr: Pointer to a rule (matching the @rule_type).
- * @flags: Must be 0 or %LANDLOCK_ADD_RULE_QUIET.
+ * @flags: Must be 0 or %LANDLOCK_ADD_RULE_QUIET and/or %LANDLOCK_ADD_RULE_NO_INHERIT.
*
* This system call enables to define a new rule and add it to an existing
* ruleset.
@@ -462,8 +466,12 @@ SYSCALL_DEFINE4(landlock_add_rule, const int, ruleset_fd,
if (!is_initialized())
return -EOPNOTSUPP;
-
- if (flags && flags != LANDLOCK_ADD_RULE_QUIET)
+ /* Checks flag existence */
+ if (flags & ~(LANDLOCK_ADD_RULE_QUIET | LANDLOCK_ADD_RULE_NO_INHERIT))
+ return -EINVAL;
+ /* No inherit may only apply on path_beneath rules. */
+ if ((flags & LANDLOCK_ADD_RULE_NO_INHERIT) &&
+ rule_type != LANDLOCK_RULE_PATH_BENEATH)
return -EINVAL;
/* Gets and checks the ruleset. */
--
2.51.0
^ permalink raw reply related
* [PATCH v5 1/6] landlock: Implement LANDLOCK_ADD_RULE_NO_INHERIT
From: Justin Suess @ 2025-12-14 17:05 UTC (permalink / raw)
To: Mickaël Salaün
Cc: Tingmao Wang, Günther Noack, Justin Suess, Jan Kara,
Abhinav Saxena, linux-security-module
In-Reply-To: <20251214170548.408142-1-utilityemal77@gmail.com>
Implements a flag to prevent access grant inheritance within the filesystem
hierarchy for landlock rules.
If a landlock rule on an inode has this flag, any access grants on parent
inodes will be ignored. Moreover, operations that involve altering the
ancestors of the subject with LANDLOCK_ADD_RULE_NO_INHERIT will be
denied up to the VFS root.
For example, if /a/b/c/ = read only + LANDLOCK_ADD_RULE_NO_INHERIT and
/ = read write, writes to files in /a/b/c will be denied. Moreover,
moving /a to /bad, removing /a/b/c, or creating links to /a will be
prohibited.
Parent flag inheritance is automatically suppressed by the permission
harvesting logic, which will finish processing early if all relevant
layers are tagged with NO_INHERIT.
The parent directory restrictions mitigate sandbox-restart attacks. For
example, if a sandboxed program is able to move a
LANDLOCK_ADD_RULE_NO_INHERIT restricted directory, upon sandbox restart,
the policy applied naively on the same filenames would be invalid.
Preventing these operations mitigates these attacks.
Because this requires path walking, to centralize the logic in a
single location, the path walking logic is moved into a helper function
landlock_walk_path_up, which takes a path as a parameter, and returns
an enum corresponding to whether the path is a mount root, real root,
or other.
Signed-off-by: Justin Suess <utilityemal77@gmail.com>
Cc: Tingmao Wang <m@maowtm.org>
Cc: Mickaël Salaün <mic@digikod.net>
---
v4..v5 changes:
* Centralized path walking logic with landlock_walk_path_up.
* Removed redundant functions in fs.c, and streamlined core
logic, removing ~120 lines of code.
* Removed mark_no_inherit_ancestors, replacing with direct flag
setting in append_fs_rule.
* Removed micro-optimization of skipping ancestor processing
when all layers have no_inherit, as it complicated the code
significantly for little gain.
v3..v4 changes:
* Rebased on v6 of Tingmao Wang's "quiet flag" series.
* Removed unnecessary mask_no_inherit_descendant_layers and related
code at Tingmao Wang's suggestion, simplifying patch.
* Updated to use new disconnected directory handling.
* Improved WARN_ON_ONCE usage. (Thanks Tingmao Wang!)
* Removed redundant loop for single-layer rulesets (again thanks Tingmao
Wang!)
* Protections now apply up to the VFS root, not just the mountpoint.
* Indentation fixes.
* Removed redundant flag marker blocked_flag_masks.
v2..v3 changes:
* Parent directory topology protections now work by lazily
inserting blank rules on parent inodes if they do not
exist. This replaces the previous xarray implementation
with simplified logic.
* Added an optimization to skip further processing if all layers
collected have no inherit.
* Added support to block flag inheritance.
include/uapi/linux/landlock.h | 29 ++++
security/landlock/fs.c | 266 +++++++++++++++++++++++++---------
security/landlock/ruleset.h | 29 +++-
3 files changed, 258 insertions(+), 66 deletions(-)
diff --git a/include/uapi/linux/landlock.h b/include/uapi/linux/landlock.h
index d4f47d20361a..6ab3e7bd1c81 100644
--- a/include/uapi/linux/landlock.h
+++ b/include/uapi/linux/landlock.h
@@ -127,10 +127,39 @@ struct landlock_ruleset_attr {
* allowed_access in the passed in rule_attr. When this flag is
* present, the caller is also allowed to pass in an empty
* allowed_access.
+ * %LANDLOCK_ADD_RULE_NO_INHERIT
+ * When set on a rule being added to a ruleset, this flag disables the
+ * inheritance of access rights and flags from parent objects.
+ *
+ * This flag currently applies only to filesystem rules. Adding it to
+ * non-filesystem rules will return -EINVAL, unless future extensions
+ * of Landlock define other hierarchical object types.
+ *
+ * By default, Landlock filesystem rules inherit allowed accesses from
+ * ancestor directories: if a parent directory grants certain rights,
+ * those rights also apply to its children. A rule marked with
+ * LANDLOCK_ADD_RULE_NO_INHERIT stops this propagation at the directory
+ * covered by the rule. Descendants of that directory continue to inherit
+ * normally unless they also have rules using this flag.
+ *
+ * If a regular file is marked with this flag, it will not inherit any
+ * access rights from its parent directories; only the accesses explicitly
+ * allowed by the rule will apply to that file.
+ *
+ * This flag also enforces parent-directory restrictions: rename, rmdir,
+ * link, and other operations that would change the directory's immediate
+ * parent subtree are denied up to the VFS root. This prevents
+ * sandboxed processes from manipulating the filesystem hierarchy to evade
+ * restrictions (e.g., via sandbox-restart attacks).
+ *
+ * In addition, this flag blocks the inheritance of rule-layer flags
+ * (such as the quiet flag) from parent directories to the object covered
+ * by this rule.
*/
/* clang-format off */
#define LANDLOCK_ADD_RULE_QUIET (1U << 0)
+#define LANDLOCK_ADD_RULE_NO_INHERIT (1U << 1)
/* clang-format on */
/**
diff --git a/security/landlock/fs.c b/security/landlock/fs.c
index 0b589263ea42..8d8623ea857f 100644
--- a/security/landlock/fs.c
+++ b/security/landlock/fs.c
@@ -317,6 +317,37 @@ static struct landlock_object *get_inode_object(struct inode *const inode)
LANDLOCK_ACCESS_FS_IOCTL_DEV)
/* clang-format on */
+enum landlock_walk_result {
+ LANDLOCK_WALK_CONTINUE,
+ LANDLOCK_WALK_STOP_REAL_ROOT,
+ LANDLOCK_WALK_MOUNT_ROOT,
+};
+
+static enum landlock_walk_result landlock_walk_path_up(struct path *const path)
+{
+ while (path->dentry == path->mnt->mnt_root) {
+ if (!follow_up(path))
+ return LANDLOCK_WALK_STOP_REAL_ROOT;
+ }
+
+ if (unlikely(IS_ROOT(path->dentry))) {
+ if (likely(path->mnt->mnt_flags & MNT_INTERNAL))
+ return LANDLOCK_WALK_MOUNT_ROOT;
+ dput(path->dentry);
+ path->dentry = dget(path->mnt->mnt_root);
+ return LANDLOCK_WALK_CONTINUE;
+ }
+
+ struct dentry *const parent = dget_parent(path->dentry);
+
+ dput(path->dentry);
+ path->dentry = parent;
+ return LANDLOCK_WALK_CONTINUE;
+}
+
+static const struct landlock_rule *find_rule(const struct landlock_ruleset *const domain,
+ const struct dentry *const dentry);
+
/*
* @path: Should have been checked by get_path_from_fd().
*/
@@ -344,6 +375,48 @@ int landlock_append_fs_rule(struct landlock_ruleset *const ruleset,
return PTR_ERR(id.key.object);
mutex_lock(&ruleset->lock);
err = landlock_insert_rule(ruleset, id, access_rights, flags);
+ if (err || !(flags & LANDLOCK_ADD_RULE_NO_INHERIT))
+ goto out_unlock;
+
+ /* Create ancestor rules and set has_no_inherit_descendant flags */
+ struct path walker = *path;
+
+ path_get(&walker);
+ while (landlock_walk_path_up(&walker) != LANDLOCK_WALK_STOP_REAL_ROOT) {
+ struct landlock_rule *ancestor_rule;
+
+ if (WARN_ON_ONCE(!walker.dentry || d_is_negative(walker.dentry))) {
+ err = -EIO;
+ break;
+ }
+
+ ancestor_rule = (struct landlock_rule *)find_rule(ruleset, walker.dentry);
+ if (!ancestor_rule) {
+ struct landlock_id ancestor_id = {
+ .type = LANDLOCK_KEY_INODE,
+ .key.object = get_inode_object(d_backing_inode(walker.dentry)),
+ };
+
+ if (IS_ERR(ancestor_id.key.object)) {
+ err = PTR_ERR(ancestor_id.key.object);
+ break;
+ }
+ err = landlock_insert_rule(ruleset, ancestor_id, 0, 0);
+ landlock_put_object(ancestor_id.key.object);
+ if (err)
+ break;
+
+ ancestor_rule = (struct landlock_rule *)
+ find_rule(ruleset, walker.dentry);
+ }
+ if (WARN_ON_ONCE(!ancestor_rule || ancestor_rule->num_layers != 1)) {
+ err = -EIO;
+ break;
+ }
+ ancestor_rule->layers[0].flags.has_no_inherit_descendant = true;
+ }
+ path_put(&walker);
+out_unlock:
mutex_unlock(&ruleset->lock);
/*
* No need to check for an error because landlock_insert_rule()
@@ -772,8 +845,10 @@ static bool is_access_to_paths_allowed(
_layer_masks_child2[LANDLOCK_NUM_ACCESS_FS];
layer_mask_t(*layer_masks_child1)[LANDLOCK_NUM_ACCESS_FS] = NULL,
(*layer_masks_child2)[LANDLOCK_NUM_ACCESS_FS] = NULL;
- struct collected_rule_flags *rule_flags_parent1 = &log_request_parent1->rule_flags;
- struct collected_rule_flags *rule_flags_parent2 = &log_request_parent2->rule_flags;
+ struct collected_rule_flags *rule_flags_parent1 =
+ &log_request_parent1->rule_flags;
+ struct collected_rule_flags *rule_flags_parent2 =
+ log_request_parent2 ? &log_request_parent2->rule_flags : NULL;
if (!access_request_parent1 && !access_request_parent2)
return true;
@@ -784,7 +859,7 @@ static bool is_access_to_paths_allowed(
if (is_nouser_or_private(path->dentry))
return true;
- if (WARN_ON_ONCE(!layer_masks_parent1))
+ if (WARN_ON_ONCE(!layer_masks_parent1 || !log_request_parent1))
return false;
allowed_parent1 = is_layer_masks_allowed(layer_masks_parent1);
@@ -851,6 +926,7 @@ static bool is_access_to_paths_allowed(
*/
while (true) {
const struct landlock_rule *rule;
+ enum landlock_walk_result walk_res;
/*
* If at least all accesses allowed on the destination are
@@ -910,46 +986,14 @@ static bool is_access_to_paths_allowed(
if (allowed_parent1 && allowed_parent2)
break;
-jump_up:
- if (walker_path.dentry == walker_path.mnt->mnt_root) {
- if (follow_up(&walker_path)) {
- /* Ignores hidden mount points. */
- goto jump_up;
- } else {
- /*
- * Stops at the real root. Denies access
- * because not all layers have granted access.
- */
- break;
- }
- }
-
- if (unlikely(IS_ROOT(walker_path.dentry))) {
- if (likely(walker_path.mnt->mnt_flags & MNT_INTERNAL)) {
- /*
- * Stops and allows access when reaching disconnected root
- * directories that are part of internal filesystems (e.g. nsfs,
- * which is reachable through /proc/<pid>/ns/<namespace>).
- */
- allowed_parent1 = true;
- allowed_parent2 = true;
- break;
- }
-
- /*
- * We reached a disconnected root directory from a bind mount.
- * Let's continue the walk with the mount point we missed.
- */
- dput(walker_path.dentry);
- walker_path.dentry = walker_path.mnt->mnt_root;
- dget(walker_path.dentry);
- } else {
- struct dentry *const parent_dentry =
- dget_parent(walker_path.dentry);
-
- dput(walker_path.dentry);
- walker_path.dentry = parent_dentry;
+ walk_res = landlock_walk_path_up(&walker_path);
+ if (walk_res == LANDLOCK_WALK_MOUNT_ROOT) {
+ allowed_parent1 = true;
+ allowed_parent2 = true;
+ break;
}
+ if (walk_res != LANDLOCK_WALK_CONTINUE)
+ break;
}
path_put(&walker_path);
@@ -963,7 +1007,7 @@ static bool is_access_to_paths_allowed(
ARRAY_SIZE(*layer_masks_parent1);
}
- if (!allowed_parent2) {
+ if (!allowed_parent2 && log_request_parent2) {
log_request_parent2->type = LANDLOCK_REQUEST_FS_ACCESS;
log_request_parent2->audit.type = LSM_AUDIT_DATA_PATH;
log_request_parent2->audit.u.path = *path;
@@ -1037,8 +1081,8 @@ static access_mask_t maybe_remove(const struct dentry *const dentry)
* collect_domain_accesses - Walk through a file path and collect accesses
*
* @domain: Domain to check against.
- * @mnt_root: Last directory to check.
- * @dir: Directory to start the walk from.
+ * @mnt_root: Last path element to check.
+ * @dir: Directory path to start the walk from.
* @layer_masks_dom: Where to store the collected accesses.
*
* This helper is useful to begin a path walk from the @dir directory to a
@@ -1060,29 +1104,31 @@ static access_mask_t maybe_remove(const struct dentry *const dentry)
*/
static bool collect_domain_accesses(
const struct landlock_ruleset *const domain,
- const struct dentry *const mnt_root, struct dentry *dir,
+ const struct path *const mnt_root, const struct path *const dir,
layer_mask_t (*const layer_masks_dom)[LANDLOCK_NUM_ACCESS_FS],
struct collected_rule_flags *const rule_flags)
{
unsigned long access_dom;
bool ret = false;
+ struct path walker;
if (WARN_ON_ONCE(!domain || !mnt_root || !dir || !layer_masks_dom))
return true;
- if (is_nouser_or_private(dir))
+ if (is_nouser_or_private(dir->dentry))
return true;
access_dom = landlock_init_layer_masks(domain, LANDLOCK_MASK_ACCESS_FS,
layer_masks_dom,
LANDLOCK_KEY_INODE);
- dget(dir);
+ walker = *dir;
+ path_get(&walker);
while (true) {
- struct dentry *parent_dentry;
+ enum landlock_walk_result walk_res;
/* Gets all layers allowing all domain accesses. */
if (landlock_unmask_layers(
- find_rule(domain, dir), access_dom, layer_masks_dom,
+ find_rule(domain, walker.dentry), access_dom, layer_masks_dom,
ARRAY_SIZE(*layer_masks_dom), rule_flags)) {
/*
* Stops when all handled accesses are allowed by at
@@ -1091,22 +1137,69 @@ static bool collect_domain_accesses(
ret = true;
break;
}
-
- /*
- * Stops at the mount point or the filesystem root for a disconnected
- * directory.
- */
- if (dir == mnt_root || unlikely(IS_ROOT(dir)))
+ if (walker.dentry == mnt_root->dentry && walker.mnt == mnt_root->mnt)
+ break;
+ walk_res = landlock_walk_path_up(&walker);
+ if (walk_res != LANDLOCK_WALK_CONTINUE)
break;
-
- parent_dentry = dget_parent(dir);
- dput(dir);
- dir = parent_dentry;
}
- dput(dir);
+ path_put(&walker);
return ret;
}
+/**
+ * deny_no_inherit_topology_change - deny topology changes on sealed paths
+ * @subject: Subject performing the operation (contains the domain).
+ * @path: Path whose dentry is the target of the topology modification.
+ *
+ * Checks whether any domain layers are sealed against topology changes at
+ * @path. If so, emit an audit record and return -EACCES. Otherwise return 0.
+ */
+static int deny_no_inherit_topology_change(const struct landlock_cred_security
+ *subject,
+ const struct path *const path)
+{
+ layer_mask_t sealed_layers = 0;
+ layer_mask_t override_layers = 0;
+ const struct landlock_rule *rule;
+ u32 layer_index;
+ unsigned long audit_layer_index;
+
+ if (WARN_ON_ONCE(!subject || !path || !path->dentry || !path->mnt ||
+ d_is_negative(path->dentry)))
+ return 0;
+
+ rule = find_rule(subject->domain, path->dentry);
+ if (!rule)
+ return 0;
+
+ for (layer_index = 0; layer_index < rule->num_layers; layer_index++) {
+ const struct landlock_layer *layer = &rule->layers[layer_index];
+ layer_mask_t layer_bit = BIT_ULL(layer->level - 1);
+
+ if (layer->flags.no_inherit ||
+ layer->flags.has_no_inherit_descendant)
+ sealed_layers |= layer_bit;
+ else
+ override_layers |= layer_bit;
+ }
+
+ sealed_layers &= ~override_layers;
+ if (!sealed_layers)
+ return 0;
+
+ audit_layer_index = __ffs((unsigned long)sealed_layers);
+ landlock_log_denial(subject, &(struct landlock_request) {
+ .type = LANDLOCK_REQUEST_FS_CHANGE_TOPOLOGY,
+ .audit = {
+ .type = LSM_AUDIT_DATA_DENTRY,
+ .u.dentry = path->dentry,
+ },
+ .layer_plus_one = audit_layer_index + 1,
+ });
+ return -EACCES;
+}
+
/**
* current_check_refer_path - Check if a rename or link action is allowed
*
@@ -1191,6 +1284,21 @@ static int current_check_refer_path(struct dentry *const old_dentry,
access_request_parent2 =
get_mode_access(d_backing_inode(old_dentry)->i_mode);
if (removable) {
+ int err = deny_no_inherit_topology_change(subject,
+ &(struct path)
+ { .mnt = new_dir->mnt,
+ .dentry = old_dentry });
+
+ if (err)
+ return err;
+ if (exchange) {
+ err = deny_no_inherit_topology_change(subject,
+ &(struct path)
+ { .mnt = new_dir->mnt,
+ .dentry = new_dentry });
+ if (err)
+ return err;
+ }
access_request_parent1 |= maybe_remove(old_dentry);
access_request_parent2 |= maybe_remove(new_dentry);
}
@@ -1232,12 +1340,15 @@ static int current_check_refer_path(struct dentry *const old_dentry,
old_dentry->d_parent;
/* new_dir->dentry is equal to new_dentry->d_parent */
- allow_parent1 = collect_domain_accesses(subject->domain, mnt_dir.dentry,
- old_parent,
+ allow_parent1 = collect_domain_accesses(subject->domain,
+ &mnt_dir,
+ &(struct path){ .mnt = new_dir->mnt,
+ .dentry = old_parent },
&layer_masks_parent1,
&request1.rule_flags);
- allow_parent2 = collect_domain_accesses(subject->domain, mnt_dir.dentry,
- new_dir->dentry,
+ allow_parent2 = collect_domain_accesses(subject->domain, &mnt_dir,
+ &(struct path){ .mnt = new_dir->mnt,
+ .dentry = new_dir->dentry },
&layer_masks_parent2,
&request2.rule_flags);
@@ -1583,12 +1694,37 @@ static int hook_path_symlink(const struct path *const dir,
static int hook_path_unlink(const struct path *const dir,
struct dentry *const dentry)
{
+ const struct landlock_cred_security *const subject =
+ landlock_get_applicable_subject(current_cred(), any_fs, NULL);
+ int err;
+
+ if (subject) {
+ err = deny_no_inherit_topology_change(subject,
+ &(struct path)
+ { .mnt = dir->mnt,
+ .dentry = dentry });
+ if (err)
+ return err;
+ }
return current_check_access_path(dir, LANDLOCK_ACCESS_FS_REMOVE_FILE);
}
static int hook_path_rmdir(const struct path *const dir,
struct dentry *const dentry)
{
+ const struct landlock_cred_security *const subject =
+ landlock_get_applicable_subject(current_cred(), any_fs, NULL);
+ int err;
+
+ if (subject) {
+ err = deny_no_inherit_topology_change(subject,
+ &(struct path)
+ { .mnt = dir->mnt,
+ .dentry = dentry });
+ if (err)
+ return err;
+ }
+
return current_check_access_path(dir, LANDLOCK_ACCESS_FS_REMOVE_DIR);
}
diff --git a/security/landlock/ruleset.h b/security/landlock/ruleset.h
index eb60db646422..81df6c56a152 100644
--- a/security/landlock/ruleset.h
+++ b/security/landlock/ruleset.h
@@ -40,6 +40,21 @@ struct landlock_layer {
* down the file hierarchy.
*/
bool quiet:1;
+ /**
+ * @no_inherit: Prevents this rule from being inherited by
+ * descendant directories in the filesystem layer. Only used
+ * for filesystem rules.
+ */
+ bool no_inherit:1;
+ /**
+ * @has_no_inherit_descendant: Marker to indicate that this layer
+ * has at least one descendant directory with a rule having the
+ * no_inherit flag. Only used for filesystem rules.
+ * This "flag" is not set by the user, but by Landlock on
+ * parent directories of rules when the child rule has
+ * a rule with the no_inherit flag.
+ */
+ bool has_no_inherit_descendant:1;
} flags;
/**
* @access: Bitfield of allowed actions on the kernel object. They are
@@ -49,13 +64,25 @@ struct landlock_layer {
};
/**
- * struct collected_rule_flags - Hold accumulated flags for each layer.
+ * struct collected_rule_flags - Hold accumulated flags and their markers for each layer.
*/
struct collected_rule_flags {
/**
* @quiet_masks: Layers for which the quiet flag is effective.
*/
layer_mask_t quiet_masks;
+ /**
+ * @no_inherit_masks: Layers for which the no_inherit flag is effective.
+ */
+ layer_mask_t no_inherit_masks;
+ /**
+ * @no_inherit_desc_masks: Layers for which the
+ * has_no_inherit_descendant tag is effective.
+ * This is not a flag itself, but a marker set on ancestors
+ * of rules with the no_inherit flag to deny topology changes
+ * in the direct parent path.
+ */
+ layer_mask_t no_inherit_desc_masks;
};
/**
--
2.51.0
^ permalink raw reply related
* [PATCH v5 0/6] Implement LANDLOCK_ADD_RULE_NO_INHERIT
From: Justin Suess @ 2025-12-14 17:05 UTC (permalink / raw)
To: Mickaël Salaün
Cc: Tingmao Wang, Günther Noack, Justin Suess, Jan Kara,
Abhinav Saxena, linux-security-module
Hi,
This is version 5 of the LANDLOCK_ADD_RULE_NO_INHERIT series, which
implements a new flag to suppress inheritance of access rights and
flags from parent objects.
This version of the series focuses on simplification and cleanup.
Behavior of the flag is identical to the previous patch.
This version has 1136 insertions(+), 72 deletions(-), down from
1285 insertions(+), 9 deletions(-), while adding documentation
and retaining all existing tests.
This series is still based on v6 of Tingmao Wang's "quiet flag" series.
Previous patch summary:
The new flag enables policies where a parent directory needs broader
access than its children. For example, a sandbox may permit read-write
access to /home/user but still prohibit writes to ~/.bashrc or
~/.ssh, even though they are nested beneath the parent. Today this is
not possible because access rights always propagate from parent to
child inodes.
When a rule is added with LANDLOCK_ADD_RULE_NO_INHERIT:
* access rights on parent inodes are ignored for that inode and its
descendants; and
* operations that change the filesystem ancestors of such objects
(via rename, rmdir, link) are denied up to the VFS root.
* parent flags do not propagate below a NO_INHERIT rule.
These parent-directory restrictions help mitigate sandbox-restart
attacks: a sandboxed process could otherwise move a protected
directory before exit, causing the next sandbox instance to apply its
policy to the wrong path.
Changes since v4:
1. Trimmed ~120 lines from core implementation in fs.c.
2. Centralized path traversal logic with a helper function
landlock_walk_path_up.
3. Fixed bug in test on applying LANDLOCK_ADD_RULE_NO_INHERIT on
a file, giving it valid access rights.
4. Restructured commits to allow independent builds.
5. Adds userspace API documentation for the flag.
Changes since v3:
1. Trimmed core implementation in fs.c by removing redundant functions.
2. Fixed placement/inclusion of prototypes.
3. Added 4 new selftests for bind mount cases.
4. Protections now apply up to the VFS root instead of the mountpoint
root.
Changes since v2:
1. Add six new selftests for the new flag.
2. Add an optimization to stop permission harvesting when all
relevant layers are tagged with NO_INHERIT.
3. Suppress inheritance of parent flags.
4. Rebase onto v5 of the quiet-flag series.
5. Remove the xarray structure used for flag tracking in favor of
blank rule insertion, simplifying the implementation.
6. Fix edge cases involving flag inheritance across multiple
NO_INHERIT layers.
7. Add documenting comments to new functions.
Links:
v1:
https://lore.kernel.org/linux-security-module/20251105180019.1432367-1-utilityemal77@gmail.com/
v2:
https://lore.kernel.org/linux-security-module/20251120222346.1157004-1-utilityemal77@gmail.com/
v3:
https://lore.kernel.org/linux-security-module/20251126122039.3832162-1-utilityemal77@gmail.com/
v4:
https://lore.kernel.org/linux-security-module/20251207015132.800576-1-utilityemal77@gmail.com/
quiet-flag v6:
https://lore.kernel.org/linux-security-module/cover.1765040503.git.m@maowtm.org/
Example usage:
# LL_FS_RO="/a/b/c" LL_FS_RW="/" LL_FS_NO_INHERIT="/a/b/c"
landlock-sandboxer sh
# touch /a/b/c/fi # denied; / RW does not inherit
# rmdir /a/b/c # denied by ancestor protections
# mv /a /bad # denied
# mkdir /a/good; touch /a/good/fi # allowed; unrelated path
About 120 lines of code have been removed from the fs.c file, achieved by
removing/streamlining many of the previous functions, and adding shared
path traversal logic.
Simplifying the path handling has a nice side effect of making some hairy
functions (is_access_to_paths_allowed) more readable.
All tests added by this series, and all other existing landlock tests,
are passing. This patch was also validated through checkpatch.pl.
Special thanks to Tingmao Wang and Mickaël Salaün for your valuable
feedback.
Thank you for your time and review.
Regards,
Justin Suess
Justin Suess (6):
landlock: Implement LANDLOCK_ADD_RULE_NO_INHERIT
landlock: Implement LANDLOCK_ADD_RULE_NO_INHERIT userspace api
samples/landlock: Add LANDLOCK_ADD_RULE_NO_INHERIT to
landlock-sandboxer
selftests/landlock: Implement selftests for
LANDLOCK_ADD_RULE_NO_INHERIT
landlock: Implement KUnit test for LANDLOCK_ADD_RULE_NO_INHERIT
landlock: Add documentation for LANDLOCK_ADD_RULE_NO_INHERIT
Documentation/userspace-api/landlock.rst | 17 +
include/uapi/linux/landlock.h | 29 +
samples/landlock/sandboxer.c | 13 +-
security/landlock/fs.c | 266 ++++++--
security/landlock/ruleset.c | 108 ++-
security/landlock/ruleset.h | 29 +-
security/landlock/syscalls.c | 16 +-
tools/testing/selftests/landlock/fs_test.c | 730 +++++++++++++++++++++
8 files changed, 1136 insertions(+), 72 deletions(-)
base-commit: 92f98eb2cc08c6e2d093d4682f1cd1204728e97e
--
2.51.0
^ permalink raw reply
* [PATCH v6 11/11] tpm-buf: Remove tpm_buf_append_handle
From: Jarkko Sakkinen @ 2025-12-14 15:38 UTC (permalink / raw)
To: linux-integrity
Cc: Ross Philipson, Jarkko Sakkinen, Peter Huewe, Jason Gunthorpe,
David Howells, Paul Moore, James Morris, Serge E. Hallyn,
open list, open list:KEYS/KEYRINGS, open list:SECURITY SUBSYSTEM
In-Reply-To: <20251214153808.73831-1-jarkko@kernel.org>
Since the number of handles is fixed to a single handle, eliminate all uses
of buf->handles and deduce values during compile-time.
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
v2:
- Streamline the code change and remove dead code.
---
drivers/char/tpm/tpm-buf.c | 26 --------------------------
drivers/char/tpm/tpm2-cmd.c | 2 +-
drivers/char/tpm/tpm2-sessions.c | 14 ++------------
include/linux/tpm.h | 2 --
4 files changed, 3 insertions(+), 41 deletions(-)
diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c
index 6134eabe6961..752c69b8a4f5 100644
--- a/drivers/char/tpm/tpm-buf.c
+++ b/drivers/char/tpm/tpm-buf.c
@@ -40,7 +40,6 @@ static void __tpm_buf_reset(struct tpm_buf *buf, u16 buf_size, u16 tag, u32 ordi
buf->flags = 0;
buf->length = sizeof(*head);
buf->capacity = buf_size - sizeof(*buf);
- buf->handles = 0;
head->tag = cpu_to_be16(tag);
head->length = cpu_to_be32(sizeof(*head));
head->ordinal = cpu_to_be32(ordinal);
@@ -56,7 +55,6 @@ static void __tpm_buf_reset_sized(struct tpm_buf *buf, u16 buf_size)
buf->flags = TPM_BUF_TPM2B;
buf->length = 2;
buf->capacity = buf_size - sizeof(*buf);
- buf->handles = 0;
buf->data[0] = 0;
buf->data[1] = 0;
}
@@ -177,30 +175,6 @@ void tpm_buf_append_u32(struct tpm_buf *buf, const u32 value)
}
EXPORT_SYMBOL_GPL(tpm_buf_append_u32);
-/**
- * tpm_buf_append_handle() - Add a handle
- * @chip: &tpm_chip instance
- * @buf: &tpm_buf instance
- * @handle: a TPM object handle
- *
- * Add a handle to the buffer, and increase the count tracking the number of
- * handles in the command buffer. Works only for command buffers.
- */
-void tpm_buf_append_handle(struct tpm_chip *chip, struct tpm_buf *buf, u32 handle)
-{
- if (buf->flags & TPM_BUF_INVALID)
- return;
-
- if (buf->flags & TPM_BUF_TPM2B) {
- dev_err(&chip->dev, "Invalid buffer type (TPM2B)\n");
- buf->flags |= TPM_BUF_INVALID;
- return;
- }
-
- tpm_buf_append_u32(buf, handle);
- buf->handles++;
-}
-
/**
* tpm_buf_read() - Read from a TPM buffer
* @buf: &tpm_buf instance
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 27069ebabe9a..f066efb54a2c 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -205,7 +205,7 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
return rc;
tpm_buf_append_hmac_session(chip, buf, 0, NULL, 0);
} else {
- tpm_buf_append_handle(chip,buf, pcr_idx);
+ tpm_buf_append_u32(buf, pcr_idx);
tpm_buf_append_auth(chip, buf, NULL, 0);
}
diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
index 8c9a7e7c82d5..f2b8ca893e15 100644
--- a/drivers/char/tpm/tpm2-sessions.c
+++ b/drivers/char/tpm/tpm2-sessions.c
@@ -261,7 +261,7 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
}
if (!tpm2_chip_auth(chip)) {
- tpm_buf_append_handle(chip, buf, handle);
+ tpm_buf_append_u32(buf, handle);
return 0;
}
@@ -288,17 +288,7 @@ EXPORT_SYMBOL_GPL(tpm_buf_append_name);
void tpm_buf_append_auth(struct tpm_chip *chip, struct tpm_buf *buf,
u8 *passphrase, int passphrase_len)
{
- /* offset tells us where the sessions area begins */
- int offset = buf->handles * 4 + TPM_HEADER_SIZE;
- u32 len = 9 + passphrase_len;
-
- if (tpm_buf_length(buf) != offset) {
- /* not the first session so update the existing length */
- len += get_unaligned_be32(&buf->data[offset]);
- put_unaligned_be32(len, &buf->data[offset]);
- } else {
- tpm_buf_append_u32(buf, len);
- }
+ tpm_buf_append_u32(buf, 9 + passphrase_len);
/* auth handle */
tpm_buf_append_u32(buf, TPM2_RS_PW);
/* nonce */
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 24b1d253e7f5..177833d6b965 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -395,7 +395,6 @@ enum tpm_buf_flags {
*/
struct tpm_buf {
u8 flags;
- u8 handles;
u16 length;
u16 capacity;
u8 data[];
@@ -441,7 +440,6 @@ void tpm_buf_append_u32(struct tpm_buf *buf, const u32 value);
u8 tpm_buf_read_u8(struct tpm_buf *buf, off_t *offset);
u16 tpm_buf_read_u16(struct tpm_buf *buf, off_t *offset);
u32 tpm_buf_read_u32(struct tpm_buf *buf, off_t *offset);
-void tpm_buf_append_handle(struct tpm_chip *chip, struct tpm_buf *buf, u32 handle);
/*
* Check if TPM device is in the firmware upgrade mode.
--
2.39.5
^ permalink raw reply related
* [PATCH v6 10/11] tpm-buf: Implement managed allocations
From: Jarkko Sakkinen @ 2025-12-14 15:38 UTC (permalink / raw)
To: linux-integrity
Cc: Ross Philipson, Jarkko Sakkinen, Stefan Berger, Peter Huewe,
Jarkko Sakkinen, Jason Gunthorpe, David Howells, Paul Moore,
James Morris, Serge E. Hallyn, James Bottomley, Mimi Zohar,
open list, open list:KEYS/KEYRINGS, open list:SECURITY SUBSYSTEM
In-Reply-To: <20251214153808.73831-1-jarkko@kernel.org>
From: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
Decouple kzalloc from buffer creation, so that a managed allocation can be
used:
struct tpm_buf *buf __free(kfree) buf = kzalloc(TPM_BUFSIZE,
GFP_KERNEL);
if (!buf)
return -ENOMEM;
tpm_buf_init(buf, TPM_BUFSIZE);
Alternatively, stack allocations are also possible:
u8 buf_data[512];
struct tpm_buf *buf = (struct tpm_buf *)buf_data;
tpm_buf_init(buf, sizeof(buf_data));
This is achieved by embedding buffer's header inside the allocated blob,
instead of having an outer wrapper.
Cc: Ross Philipson <ross.philipson@oracle.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
---
drivers/char/tpm/tpm-buf.c | 124 ++++++----
drivers/char/tpm/tpm-interface.c | 66 +++---
drivers/char/tpm/tpm-sysfs.c | 21 +-
drivers/char/tpm/tpm.h | 1 -
drivers/char/tpm/tpm1-cmd.c | 129 +++++------
drivers/char/tpm/tpm2-cmd.c | 266 ++++++++++------------
drivers/char/tpm/tpm2-sessions.c | 142 ++++++------
drivers/char/tpm/tpm2-space.c | 44 ++--
drivers/char/tpm/tpm_vtpm_proxy.c | 30 ++-
include/linux/tpm.h | 20 +-
security/keys/trusted-keys/trusted_tpm1.c | 36 +--
security/keys/trusted-keys/trusted_tpm2.c | 173 +++++++-------
12 files changed, 500 insertions(+), 552 deletions(-)
diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c
index 69ee77400539..6134eabe6961 100644
--- a/drivers/char/tpm/tpm-buf.c
+++ b/drivers/char/tpm/tpm-buf.c
@@ -7,82 +7,109 @@
#include <linux/module.h>
#include <linux/tpm.h>
-/**
- * tpm_buf_init() - Allocate and initialize a TPM command
- * @buf: A &tpm_buf
- * @tag: TPM_TAG_RQU_COMMAND, TPM2_ST_NO_SESSIONS or TPM2_ST_SESSIONS
- * @ordinal: A command ordinal
- *
- * Return: 0 or -ENOMEM
- */
-int tpm_buf_init(struct tpm_buf *buf, u16 tag, u32 ordinal)
+static void __tpm_buf_size_invariant(struct tpm_buf *buf, u16 buf_size)
{
- buf->data = (u8 *)__get_free_page(GFP_KERNEL);
- if (!buf->data)
- return -ENOMEM;
-
- tpm_buf_reset(buf, tag, ordinal);
- return 0;
+ u32 buf_size_2 = (u32)buf->capacity + (u32)sizeof(*buf);
+
+ if (!buf->capacity) {
+ if (buf_size > TPM_BUFSIZE) {
+ WARN(1, "%s: size overflow: %u\n", __func__, buf_size);
+ buf->flags |= TPM_BUF_INVALID;
+ }
+ } else {
+ if (buf_size != buf_size_2) {
+ WARN(1, "%s: size mismatch: %u != %u\n", __func__, buf_size,
+ buf_size_2);
+ buf->flags |= TPM_BUF_INVALID;
+ }
+ }
}
-EXPORT_SYMBOL_GPL(tpm_buf_init);
-/**
- * tpm_buf_reset() - Initialize a TPM command
- * @buf: A &tpm_buf
- * @tag: TPM_TAG_RQU_COMMAND, TPM2_ST_NO_SESSIONS or TPM2_ST_SESSIONS
- * @ordinal: A command ordinal
- */
-void tpm_buf_reset(struct tpm_buf *buf, u16 tag, u32 ordinal)
+static void __tpm_buf_reset(struct tpm_buf *buf, u16 buf_size, u16 tag, u32 ordinal)
{
struct tpm_header *head = (struct tpm_header *)buf->data;
+ __tpm_buf_size_invariant(buf, buf_size);
+
+ if (buf->flags & TPM_BUF_INVALID)
+ return;
+
WARN_ON(tag != TPM_TAG_RQU_COMMAND && tag != TPM2_ST_NO_SESSIONS &&
tag != TPM2_ST_SESSIONS && tag != 0);
buf->flags = 0;
buf->length = sizeof(*head);
+ buf->capacity = buf_size - sizeof(*buf);
+ buf->handles = 0;
head->tag = cpu_to_be16(tag);
head->length = cpu_to_be32(sizeof(*head));
head->ordinal = cpu_to_be32(ordinal);
+}
+
+static void __tpm_buf_reset_sized(struct tpm_buf *buf, u16 buf_size)
+{
+ __tpm_buf_size_invariant(buf, buf_size);
+
+ if (buf->flags & TPM_BUF_INVALID)
+ return;
+
+ buf->flags = TPM_BUF_TPM2B;
+ buf->length = 2;
+ buf->capacity = buf_size - sizeof(*buf);
buf->handles = 0;
+ buf->data[0] = 0;
+ buf->data[1] = 0;
}
-EXPORT_SYMBOL_GPL(tpm_buf_reset);
/**
- * tpm_buf_init_sized() - Allocate and initialize a sized (TPM2B) buffer
- * @buf: A @tpm_buf
- *
- * Return: 0 or -ENOMEM
+ * tpm_buf_init() - Initialize a TPM command
+ * @buf: A &tpm_buf
+ * @buf_size: Size of the buffer.
*/
-int tpm_buf_init_sized(struct tpm_buf *buf)
+void tpm_buf_init(struct tpm_buf *buf, u16 buf_size)
{
- buf->data = (u8 *)__get_free_page(GFP_KERNEL);
- if (!buf->data)
- return -ENOMEM;
+ memset(buf, 0, buf_size);
+ __tpm_buf_reset(buf, buf_size, TPM_TAG_RQU_COMMAND, 0);
+}
+EXPORT_SYMBOL_GPL(tpm_buf_init);
- tpm_buf_reset_sized(buf);
- return 0;
+/**
+ * tpm_buf_init_sized() - Initialize a sized buffer
+ * @buf: A &tpm_buf
+ * @buf_size: Size of the buffer.
+ */
+void tpm_buf_init_sized(struct tpm_buf *buf, u16 buf_size)
+{
+ memset(buf, 0, buf_size);
+ __tpm_buf_reset_sized(buf, buf_size);
}
EXPORT_SYMBOL_GPL(tpm_buf_init_sized);
/**
- * tpm_buf_reset_sized() - Initialize a sized buffer
+ * tpm_buf_reset() - Re-initialize a TPM command
* @buf: A &tpm_buf
+ * @tag: TPM_TAG_RQU_COMMAND, TPM2_ST_NO_SESSIONS or TPM2_ST_SESSIONS
+ * @ordinal: A command ordinal
*/
-void tpm_buf_reset_sized(struct tpm_buf *buf)
+void tpm_buf_reset(struct tpm_buf *buf, u16 tag, u32 ordinal)
{
- buf->flags = TPM_BUF_TPM2B;
- buf->length = 2;
- buf->data[0] = 0;
- buf->data[1] = 0;
+ u16 buf_size = buf->capacity + sizeof(*buf);
+
+ __tpm_buf_reset(buf, buf_size, tag, ordinal);
}
-EXPORT_SYMBOL_GPL(tpm_buf_reset_sized);
+EXPORT_SYMBOL_GPL(tpm_buf_reset);
-void tpm_buf_destroy(struct tpm_buf *buf)
+/**
+ * tpm_buf_reset_sized() - Re-initialize a sized buffer
+ * @buf: A &tpm_buf
+ */
+void tpm_buf_reset_sized(struct tpm_buf *buf)
{
- free_page((unsigned long)buf->data);
+ u16 buf_size = buf->capacity + sizeof(*buf);
+
+ __tpm_buf_reset_sized(buf, buf_size);
}
-EXPORT_SYMBOL_GPL(tpm_buf_destroy);
+EXPORT_SYMBOL_GPL(tpm_buf_reset_sized);
/**
* tpm_buf_length() - Return the number of bytes consumed by the data
@@ -90,8 +117,11 @@ EXPORT_SYMBOL_GPL(tpm_buf_destroy);
*
* Return: The number of bytes consumed by the buffer
*/
-u32 tpm_buf_length(struct tpm_buf *buf)
+u16 tpm_buf_length(struct tpm_buf *buf)
{
+ if (buf->flags & TPM_BUF_INVALID)
+ return 0;
+
return buf->length;
}
EXPORT_SYMBOL_GPL(tpm_buf_length);
@@ -104,10 +134,12 @@ EXPORT_SYMBOL_GPL(tpm_buf_length);
*/
void tpm_buf_append(struct tpm_buf *buf, const u8 *new_data, u16 new_length)
{
+ u32 total_length = (u32)buf->length + (u32)new_length;
+
if (buf->flags & TPM_BUF_INVALID)
return;
- if ((buf->length + new_length) > PAGE_SIZE) {
+ if (total_length > (u32)buf->capacity) {
WARN(1, "tpm_buf: write overflow\n");
buf->flags |= TPM_BUF_INVALID;
return;
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 021553e8a314..594ad095a90b 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -494,46 +494,38 @@ struct tpm1_get_random_out {
static int tpm1_get_random(struct tpm_chip *chip, u8 *out, size_t max)
{
struct tpm1_get_random_out *resp;
- struct tpm_buf buf;
u32 recd;
int rc;
if (!out || !max || max > TPM_MAX_RNG_DATA)
return -EINVAL;
- rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GETRANDOM);
- if (rc)
- return rc;
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
- tpm_buf_append_u32(&buf, max);
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GETRANDOM);
+ tpm_buf_append_u32(buf, max);
- rc = tpm_transmit_cmd(chip, &buf, sizeof(resp->rng_data_len), "TPM_GetRandom");
+ rc = tpm_transmit_cmd(chip, buf, sizeof(resp->rng_data_len), "TPM_GetRandom");
if (rc) {
if (rc > 0)
rc = -EIO;
- goto err;
+ return rc;
}
- resp = (struct tpm1_get_random_out *)&buf.data[TPM_HEADER_SIZE];
+ resp = (struct tpm1_get_random_out *)&buf->data[TPM_HEADER_SIZE];
recd = be32_to_cpu(resp->rng_data_len);
- if (recd > max) {
- rc = -EIO;
- goto err;
- }
+ if (recd > max)
+ return -EIO;
- if (buf.length < TPM_HEADER_SIZE + sizeof(resp->rng_data_len) + recd) {
- rc = -EIO;
- goto err;
- }
+ if (buf->length < TPM_HEADER_SIZE + sizeof(resp->rng_data_len) + recd)
+ return -EIO;
memcpy(out, resp->rng_data, recd);
- tpm_buf_destroy(&buf);
return recd;
-
-err:
- tpm_buf_destroy(&buf);
- return rc;
}
struct tpm2_get_random_out {
@@ -545,7 +537,6 @@ static int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
{
struct tpm2_get_random_out *resp;
struct tpm_header *head;
- struct tpm_buf buf;
off_t offset;
u32 recd;
int ret;
@@ -553,30 +544,30 @@ static int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
if (!out || !max || max > TPM_MAX_RNG_DATA)
return -EINVAL;
- ret = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_GET_RANDOM);
- if (ret)
- return ret;
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_GET_RANDOM);
if (tpm2_chip_auth(chip)) {
- tpm_buf_append_hmac_session(chip, &buf,
+ tpm_buf_append_hmac_session(chip, buf,
TPM2_SA_ENCRYPT | TPM2_SA_CONTINUE_SESSION,
NULL, 0);
} else {
- head = (struct tpm_header *)buf.data;
+ head = (struct tpm_header *)buf->data;
head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
}
- tpm_buf_append_u16(&buf, max);
+ tpm_buf_append_u16(buf, max);
- ret = tpm_buf_fill_hmac_session(chip, &buf);
- if (ret) {
- tpm_buf_destroy(&buf);
+ ret = tpm_buf_fill_hmac_session(chip, buf);
+ if (ret)
return ret;
- }
- ret = tpm_transmit_cmd(chip, &buf, offsetof(struct tpm2_get_random_out, buffer),
+ ret = tpm_transmit_cmd(chip, buf, offsetof(struct tpm2_get_random_out, buffer),
"TPM2_GetRandom");
- ret = tpm_buf_check_hmac_response(chip, &buf, ret);
+ ret = tpm_buf_check_hmac_response(chip, buf, ret);
if (ret) {
if (ret > 0)
ret = -EIO;
@@ -584,17 +575,17 @@ static int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
goto out;
}
- head = (struct tpm_header *)buf.data;
+ head = (struct tpm_header *)buf->data;
offset = TPM_HEADER_SIZE;
/* Skip the parameter size field: */
if (be16_to_cpu(head->tag) == TPM2_ST_SESSIONS)
offset += 4;
- resp = (struct tpm2_get_random_out *)&buf.data[offset];
+ resp = (struct tpm2_get_random_out *)&buf->data[offset];
recd = min_t(u32, be16_to_cpu(resp->size), max);
- if (tpm_buf_length(&buf) <
+ if (tpm_buf_length(buf) <
TPM_HEADER_SIZE + offsetof(struct tpm2_get_random_out, buffer) + recd) {
ret = -EIO;
goto out;
@@ -605,7 +596,6 @@ static int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
out:
tpm2_end_auth_session(chip);
- tpm_buf_destroy(&buf);
return ret;
}
diff --git a/drivers/char/tpm/tpm-sysfs.c b/drivers/char/tpm/tpm-sysfs.c
index 4a6a27ee295d..0f321c307bc6 100644
--- a/drivers/char/tpm/tpm-sysfs.c
+++ b/drivers/char/tpm/tpm-sysfs.c
@@ -32,28 +32,29 @@ struct tpm_readpubek_out {
static ssize_t pubek_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
- struct tpm_buf tpm_buf;
struct tpm_readpubek_out *out;
int i;
char *str = buf;
struct tpm_chip *chip = to_tpm_chip(dev);
char anti_replay[20];
+ struct tpm_buf *tpm_buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!tpm_buf)
+ return -ENOMEM;
+
memset(&anti_replay, 0, sizeof(anti_replay));
if (tpm_try_get_ops(chip))
return 0;
- if (tpm_buf_init(&tpm_buf, TPM_TAG_RQU_COMMAND, TPM_ORD_READPUBEK))
- goto out_ops;
-
- tpm_buf_append(&tpm_buf, anti_replay, sizeof(anti_replay));
+ tpm_buf_init(tpm_buf, TPM_BUFSIZE);
+ tpm_buf_reset(tpm_buf, TPM_TAG_RQU_COMMAND, TPM_ORD_READPUBEK);
+ tpm_buf_append(tpm_buf, anti_replay, sizeof(anti_replay));
- if (tpm_transmit_cmd(chip, &tpm_buf, READ_PUBEK_RESULT_MIN_BODY_SIZE,
- "attempting to read the PUBEK"))
- goto out_buf;
+ if (tpm_transmit_cmd(chip, tpm_buf, READ_PUBEK_RESULT_MIN_BODY_SIZE, "TPM_ReadPubek"))
+ goto out_ops;
- out = (struct tpm_readpubek_out *)&tpm_buf.data[10];
+ out = (struct tpm_readpubek_out *)&tpm_buf->data[10];
str +=
sprintf(str,
"Algorithm: %4ph\n"
@@ -71,8 +72,6 @@ static ssize_t pubek_show(struct device *dev, struct device_attribute *attr,
for (i = 0; i < 256; i += 16)
str += sprintf(str, "%16ph\n", &out->modulus[i]);
-out_buf:
- tpm_buf_destroy(&tpm_buf);
out_ops:
tpm_put_ops(chip);
return str - buf;
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index f698d01401de..c4bbd8f04605 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -32,7 +32,6 @@
#endif
#define TPM_MINOR 224 /* officially assigned */
-#define TPM_BUFSIZE 4096
#define TPM_NUM_DEVICES 65536
#define TPM_RETRY 50
diff --git a/drivers/char/tpm/tpm1-cmd.c b/drivers/char/tpm/tpm1-cmd.c
index 0604e11c9778..d8f16e66666b 100644
--- a/drivers/char/tpm/tpm1-cmd.c
+++ b/drivers/char/tpm/tpm1-cmd.c
@@ -323,20 +323,14 @@ unsigned long tpm1_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
*/
static int tpm1_startup(struct tpm_chip *chip)
{
- struct tpm_buf buf;
- int rc;
-
- dev_info(&chip->dev, "starting up the TPM manually\n");
-
- rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_STARTUP);
- if (rc < 0)
- return rc;
-
- tpm_buf_append_u16(&buf, TPM_ST_CLEAR);
-
- rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to start the TPM");
- tpm_buf_destroy(&buf);
- return rc;
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_STARTUP);
+ tpm_buf_append_u16(buf, TPM_ST_CLEAR);
+ return tpm_transmit_cmd(chip, buf, 0, "TPM_Startup");
}
int tpm1_get_timeouts(struct tpm_chip *chip)
@@ -463,50 +457,47 @@ int tpm1_get_timeouts(struct tpm_chip *chip)
int tpm1_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash,
const char *log_msg)
{
- struct tpm_buf buf;
- int rc;
-
- rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_PCR_EXTEND);
- if (rc)
- return rc;
-
- tpm_buf_append_u32(&buf, pcr_idx);
- tpm_buf_append(&buf, hash, TPM_DIGEST_SIZE);
-
- rc = tpm_transmit_cmd(chip, &buf, TPM_DIGEST_SIZE, log_msg);
- tpm_buf_destroy(&buf);
- return rc;
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_PCR_EXTEND);
+ tpm_buf_append_u32(buf, pcr_idx);
+ tpm_buf_append(buf, hash, TPM_DIGEST_SIZE);
+ return tpm_transmit_cmd(chip, buf, TPM_DIGEST_SIZE, log_msg);
}
#define TPM_ORD_GET_CAP 101
ssize_t tpm1_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
const char *desc, size_t min_cap_length)
{
- struct tpm_buf buf;
int rc;
- rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_CAP);
- if (rc)
- return rc;
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_CAP);
if (subcap_id == TPM_CAP_VERSION_1_1 ||
subcap_id == TPM_CAP_VERSION_1_2) {
- tpm_buf_append_u32(&buf, subcap_id);
- tpm_buf_append_u32(&buf, 0);
+ tpm_buf_append_u32(buf, subcap_id);
+ tpm_buf_append_u32(buf, 0);
} else {
if (subcap_id == TPM_CAP_FLAG_PERM ||
subcap_id == TPM_CAP_FLAG_VOL)
- tpm_buf_append_u32(&buf, TPM_CAP_FLAG);
+ tpm_buf_append_u32(buf, TPM_CAP_FLAG);
else
- tpm_buf_append_u32(&buf, TPM_CAP_PROP);
+ tpm_buf_append_u32(buf, TPM_CAP_PROP);
- tpm_buf_append_u32(&buf, 4);
- tpm_buf_append_u32(&buf, subcap_id);
+ tpm_buf_append_u32(buf, 4);
+ tpm_buf_append_u32(buf, subcap_id);
}
- rc = tpm_transmit_cmd(chip, &buf, min_cap_length, desc);
+ rc = tpm_transmit_cmd(chip, buf, min_cap_length, desc);
if (!rc)
- *cap = *(cap_t *)&buf.data[TPM_HEADER_SIZE + 4];
- tpm_buf_destroy(&buf);
+ *cap = *(cap_t *)&buf->data[TPM_HEADER_SIZE + 4];
return rc;
}
EXPORT_SYMBOL_GPL(tpm1_getcap);
@@ -514,29 +505,24 @@ EXPORT_SYMBOL_GPL(tpm1_getcap);
#define TPM_ORD_PCRREAD 21
int tpm1_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf)
{
- struct tpm_buf buf;
int rc;
- rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_PCRREAD);
- if (rc)
- return rc;
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
- tpm_buf_append_u32(&buf, pcr_idx);
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_PCRREAD);
+ tpm_buf_append_u32(buf, pcr_idx);
- rc = tpm_transmit_cmd(chip, &buf, TPM_DIGEST_SIZE,
- "attempting to read a pcr value");
+ rc = tpm_transmit_cmd(chip, buf, TPM_DIGEST_SIZE, "TPM_PCRRead");
if (rc)
- goto out;
-
- if (tpm_buf_length(&buf) < TPM_DIGEST_SIZE) {
- rc = -EFAULT;
- goto out;
- }
+ return rc;
- memcpy(res_buf, &buf.data[TPM_HEADER_SIZE], TPM_DIGEST_SIZE);
+ if (buf->length < TPM_DIGEST_SIZE)
+ return -EFAULT;
-out:
- tpm_buf_destroy(&buf);
+ memcpy(res_buf, &buf->data[TPM_HEADER_SIZE], TPM_DIGEST_SIZE);
return rc;
}
@@ -550,16 +536,13 @@ int tpm1_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf)
*/
static int tpm1_continue_selftest(struct tpm_chip *chip)
{
- struct tpm_buf buf;
- int rc;
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
- rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_CONTINUE_SELFTEST);
- if (rc)
- return rc;
-
- rc = tpm_transmit_cmd(chip, &buf, 0, "continue selftest");
- tpm_buf_destroy(&buf);
- return rc;
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_CONTINUE_SELFTEST);
+ return tpm_transmit_cmd(chip, buf, 0, "TPM_ContinueSelfTest");
}
/**
@@ -673,22 +656,24 @@ int tpm1_auto_startup(struct tpm_chip *chip)
int tpm1_pm_suspend(struct tpm_chip *chip, u32 tpm_suspend_pcr)
{
u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
- struct tpm_buf buf;
unsigned int try;
int rc;
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
/* for buggy tpm, flush pcrs with extend to selected dummy */
if (tpm_suspend_pcr)
rc = tpm1_pcr_extend(chip, tpm_suspend_pcr, dummy_hash,
"extending dummy pcr before suspend");
- rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_SAVESTATE);
- if (rc)
- return rc;
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_SAVESTATE);
+
/* now do the actual savestate */
for (try = 0; try < TPM_RETRY; try++) {
- rc = tpm_transmit_cmd(chip, &buf, 0, NULL);
+ rc = tpm_transmit_cmd(chip, buf, 0, NULL);
/*
* If the TPM indicates that it is too busy to respond to
* this command then retry before giving up. It can take
@@ -703,7 +688,7 @@ int tpm1_pm_suspend(struct tpm_chip *chip, u32 tpm_suspend_pcr)
break;
tpm_msleep(TPM_TIMEOUT_RETRY);
- tpm_buf_reset(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_SAVESTATE);
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_SAVESTATE);
}
if (rc)
@@ -713,8 +698,6 @@ int tpm1_pm_suspend(struct tpm_chip *chip, u32 tpm_suspend_pcr)
dev_warn(&chip->dev, "TPM savestate took %dms\n",
try * TPM_TIMEOUT_RETRY);
- tpm_buf_destroy(&buf);
-
return rc;
}
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 461e85c3abe5..27069ebabe9a 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -119,12 +119,15 @@ int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
{
int i;
int rc;
- struct tpm_buf buf;
struct tpm2_pcr_read_out *out;
u8 pcr_select[TPM2_PCR_SELECT_MIN] = {0};
u16 digest_size;
u16 expected_digest_size = 0;
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
if (pcr_idx >= TPM2_PLATFORM_PCR)
return -EINVAL;
@@ -139,36 +142,31 @@ int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
expected_digest_size = chip->allocated_banks[i].digest_size;
}
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_PCR_READ);
- if (rc)
- return rc;
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_PCR_READ);
pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
- tpm_buf_append_u32(&buf, 1);
- tpm_buf_append_u16(&buf, digest->alg_id);
- tpm_buf_append_u8(&buf, TPM2_PCR_SELECT_MIN);
- tpm_buf_append(&buf, (const unsigned char *)pcr_select,
+ tpm_buf_append_u32(buf, 1);
+ tpm_buf_append_u16(buf, digest->alg_id);
+ tpm_buf_append_u8(buf, TPM2_PCR_SELECT_MIN);
+ tpm_buf_append(buf, (const unsigned char *)pcr_select,
sizeof(pcr_select));
- rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to read a pcr value");
+ rc = tpm_transmit_cmd(chip, buf, 0, "TPM2_PCR_Read");
if (rc)
- goto out;
+ return rc;
- out = (struct tpm2_pcr_read_out *)&buf.data[TPM_HEADER_SIZE];
+ out = (struct tpm2_pcr_read_out *)&buf->data[TPM_HEADER_SIZE];
digest_size = be16_to_cpu(out->digest_size);
if (digest_size > sizeof(digest->digest) ||
- (!digest_size_ptr && digest_size != expected_digest_size)) {
- rc = -EINVAL;
- goto out;
- }
+ (!digest_size_ptr && digest_size != expected_digest_size))
+ return rc;
if (digest_size_ptr)
*digest_size_ptr = digest_size;
memcpy(digest->digest, out->digest, digest_size);
-out:
- tpm_buf_destroy(&buf);
return rc;
}
@@ -184,57 +182,53 @@ int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
struct tpm_digest *digests)
{
- struct tpm_buf buf;
int rc;
int i;
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
if (!disable_pcr_integrity) {
rc = tpm2_start_auth_session(chip);
if (rc)
return rc;
}
- rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND);
- if (rc) {
- if (!disable_pcr_integrity)
- tpm2_end_auth_session(chip);
- return rc;
- }
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND);
if (!disable_pcr_integrity) {
- rc = tpm_buf_append_name(chip, &buf, pcr_idx, (u8 *)&pcr_idx,
+ rc = tpm_buf_append_name(chip, buf, pcr_idx, (u8 *)&pcr_idx,
sizeof(u32));
- if (rc) {
- tpm_buf_destroy(&buf);
+ if (rc)
return rc;
- }
- tpm_buf_append_hmac_session(chip, &buf, 0, NULL, 0);
+ tpm_buf_append_hmac_session(chip, buf, 0, NULL, 0);
} else {
- tpm_buf_append_handle(chip, &buf, pcr_idx);
- tpm_buf_append_auth(chip, &buf, NULL, 0);
+ tpm_buf_append_handle(chip,buf, pcr_idx);
+ tpm_buf_append_auth(chip, buf, NULL, 0);
}
- tpm_buf_append_u32(&buf, chip->nr_allocated_banks);
+ tpm_buf_append_u32(buf, chip->nr_allocated_banks);
for (i = 0; i < chip->nr_allocated_banks; i++) {
- tpm_buf_append_u16(&buf, digests[i].alg_id);
- tpm_buf_append(&buf, (const unsigned char *)&digests[i].digest,
+ tpm_buf_append_u16(buf, digests[i].alg_id);
+ tpm_buf_append(buf, (const unsigned char *)&digests[i].digest,
chip->allocated_banks[i].digest_size);
}
+ if (buf->flags & TPM_BUF_INVALID)
+ return -EINVAL;
if (!disable_pcr_integrity) {
- rc = tpm_buf_fill_hmac_session(chip, &buf);
- if (rc) {
- tpm_buf_destroy(&buf);
+ rc = tpm_buf_fill_hmac_session(chip, buf);
+ if (rc)
return rc;
- }
}
- rc = tpm_transmit_cmd(chip, &buf, 0, "attempting extend a PCR value");
- if (!disable_pcr_integrity)
- rc = tpm_buf_check_hmac_response(chip, &buf, rc);
+ rc = tpm_transmit_cmd(chip, buf, 0, "TPM2_PCR_Extend");
- tpm_buf_destroy(&buf);
+ if (!disable_pcr_integrity)
+ rc = tpm_buf_check_hmac_response(chip, buf, rc);
return rc;
}
@@ -246,20 +240,18 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
*/
void tpm2_flush_context(struct tpm_chip *chip, u32 handle)
{
- struct tpm_buf buf;
- int rc;
-
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
- if (rc) {
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf) {
dev_warn(&chip->dev, "0x%08x was not flushed, out of memory\n",
handle);
return;
}
- tpm_buf_append_u32(&buf, handle);
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
+ tpm_buf_append_u32(buf, handle);
- tpm_transmit_cmd(chip, &buf, 0, "flushing context");
- tpm_buf_destroy(&buf);
+ tpm_transmit_cmd(chip, buf, 0, "TPM2_FlushContext");
}
EXPORT_SYMBOL_GPL(tpm2_flush_context);
@@ -286,19 +278,20 @@ ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id, u32 *value,
const char *desc)
{
struct tpm2_get_cap_out *out;
- struct tpm_buf buf;
int rc;
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
- if (rc)
- return rc;
- tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
- tpm_buf_append_u32(&buf, property_id);
- tpm_buf_append_u32(&buf, 1);
- rc = tpm_transmit_cmd(chip, &buf, 0, NULL);
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
+ tpm_buf_append_u32(buf, TPM2_CAP_TPM_PROPERTIES);
+ tpm_buf_append_u32(buf, property_id);
+ tpm_buf_append_u32(buf, 1);
+ rc = tpm_transmit_cmd(chip, buf, 0, NULL);
if (!rc) {
- out = (struct tpm2_get_cap_out *)
- &buf.data[TPM_HEADER_SIZE];
+ out = (struct tpm2_get_cap_out *)&buf->data[TPM_HEADER_SIZE];
/*
* To prevent failing boot up of some systems, Infineon TPM2.0
* returns SUCCESS on TPM2_Startup in field upgrade mode. Also
@@ -310,7 +303,6 @@ ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id, u32 *value,
else
rc = -ENODATA;
}
- tpm_buf_destroy(&buf);
return rc;
}
EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt);
@@ -327,15 +319,14 @@ EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt);
*/
void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
{
- struct tpm_buf buf;
- int rc;
-
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SHUTDOWN);
- if (rc)
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
return;
- tpm_buf_append_u16(&buf, shutdown_type);
- tpm_transmit_cmd(chip, &buf, 0, "stopping the TPM");
- tpm_buf_destroy(&buf);
+
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SHUTDOWN);
+ tpm_buf_append_u16(buf, shutdown_type);
+ tpm_transmit_cmd(chip, buf, 0, "TPM2_Shutdown");
}
/**
@@ -353,20 +344,19 @@ void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
*/
static int tpm2_do_selftest(struct tpm_chip *chip)
{
- struct tpm_buf buf;
int full;
int rc;
- for (full = 0; full < 2; full++) {
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SELF_TEST);
- if (rc)
- return rc;
-
- tpm_buf_append_u8(&buf, full);
- rc = tpm_transmit_cmd(chip, &buf, 0,
- "attempting the self test");
- tpm_buf_destroy(&buf);
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SELF_TEST);
+ for (full = 0; full < 2; full++) {
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SELF_TEST);
+ tpm_buf_append_u8(buf, full);
+ rc = tpm_transmit_cmd(chip, buf, 0, "TPM2_SelfTest");
if (rc == TPM2_RC_TESTING)
rc = TPM2_RC_SUCCESS;
if (rc == TPM2_RC_INITIALIZE || rc == TPM2_RC_SUCCESS)
@@ -391,23 +381,24 @@ static int tpm2_do_selftest(struct tpm_chip *chip)
int tpm2_probe(struct tpm_chip *chip)
{
struct tpm_header *out;
- struct tpm_buf buf;
int rc;
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
- if (rc)
- return rc;
- tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
- tpm_buf_append_u32(&buf, TPM_PT_TOTAL_COMMANDS);
- tpm_buf_append_u32(&buf, 1);
- rc = tpm_transmit_cmd(chip, &buf, 0, NULL);
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
+ tpm_buf_append_u32(buf, TPM2_CAP_TPM_PROPERTIES);
+ tpm_buf_append_u32(buf, TPM_PT_TOTAL_COMMANDS);
+ tpm_buf_append_u32(buf, 1);
+ rc = tpm_transmit_cmd(chip, buf, 0, NULL);
/* We ignore TPM return codes on purpose. */
if (rc >= 0) {
- out = (struct tpm_header *)buf.data;
+ out = (struct tpm_header *)buf->data;
if (be16_to_cpu(out->tag) == TPM2_ST_NO_SESSIONS)
chip->flags |= TPM_CHIP_FLAG_TPM2;
}
- tpm_buf_destroy(&buf);
return 0;
}
EXPORT_SYMBOL_GPL(tpm2_probe);
@@ -447,7 +438,6 @@ struct tpm2_pcr_selection {
ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
{
struct tpm2_pcr_selection pcr_selection;
- struct tpm_buf buf;
void *marker;
void *end;
void *pcr_select_offset;
@@ -459,39 +449,37 @@ ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
int rc;
int i = 0;
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
- if (rc)
- return rc;
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
- tpm_buf_append_u32(&buf, TPM2_CAP_PCRS);
- tpm_buf_append_u32(&buf, 0);
- tpm_buf_append_u32(&buf, 1);
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
+ tpm_buf_append_u32(buf, TPM2_CAP_PCRS);
+ tpm_buf_append_u32(buf, 0);
+ tpm_buf_append_u32(buf, 1);
- rc = tpm_transmit_cmd(chip, &buf, 9, "get tpm pcr allocation");
+ rc = tpm_transmit_cmd(chip, buf, 9, "TPM2_GetCapability(PCRS)");
if (rc)
- goto out;
+ return rc;
- nr_possible_banks = be32_to_cpup(
- (__be32 *)&buf.data[TPM_HEADER_SIZE + 5]);
+ nr_possible_banks = be32_to_cpup((__be32 *)&buf->data[TPM_HEADER_SIZE + 5]);
if (nr_possible_banks > TPM2_MAX_PCR_BANKS) {
pr_err("tpm: out of bank capacity: %u > %u\n",
nr_possible_banks, TPM2_MAX_PCR_BANKS);
- rc = -ENOMEM;
- goto out;
+ return -ENOMEM;
}
- marker = &buf.data[TPM_HEADER_SIZE + 9];
+ marker = &buf->data[TPM_HEADER_SIZE + 9];
- rsp_len = be32_to_cpup((__be32 *)&buf.data[2]);
- end = &buf.data[rsp_len];
+ rsp_len = be32_to_cpup((__be32 *)&buf->data[2]);
+ end = &buf->data[rsp_len];
for (i = 0; i < nr_possible_banks; i++) {
pcr_select_offset = marker +
offsetof(struct tpm2_pcr_selection, size_of_select);
- if (pcr_select_offset >= end) {
- rc = -EFAULT;
- break;
- }
+ if (pcr_select_offset >= end)
+ return -EFAULT;
memcpy(&pcr_selection, marker, sizeof(pcr_selection));
hash_alg = be16_to_cpu(pcr_selection.hash_alg);
@@ -503,7 +491,7 @@ ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
rc = tpm2_init_bank_info(chip, nr_alloc_banks);
if (rc < 0)
- break;
+ return rc;
nr_alloc_banks++;
}
@@ -515,21 +503,21 @@ ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
}
chip->nr_allocated_banks = nr_alloc_banks;
-out:
- tpm_buf_destroy(&buf);
-
- return rc;
+ return 0;
}
int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
{
- struct tpm_buf buf;
u32 nr_commands;
__be32 *attrs;
u32 cc;
int i;
int rc;
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
rc = tpm2_get_tpm_pt(chip, TPM_PT_TOTAL_COMMANDS, &nr_commands, NULL);
if (rc)
goto out;
@@ -546,30 +534,24 @@ int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
goto out;
}
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
- if (rc)
- goto out;
-
- tpm_buf_append_u32(&buf, TPM2_CAP_COMMANDS);
- tpm_buf_append_u32(&buf, TPM2_CC_FIRST);
- tpm_buf_append_u32(&buf, nr_commands);
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
+ tpm_buf_append_u32(buf, TPM2_CAP_COMMANDS);
+ tpm_buf_append_u32(buf, TPM2_CC_FIRST);
+ tpm_buf_append_u32(buf, nr_commands);
- rc = tpm_transmit_cmd(chip, &buf, 9 + 4 * nr_commands, NULL);
- if (rc) {
- tpm_buf_destroy(&buf);
+ rc = tpm_transmit_cmd(chip, buf, 9 + 4 * nr_commands, NULL);
+ if (rc)
goto out;
- }
- if (nr_commands !=
- be32_to_cpup((__be32 *)&buf.data[TPM_HEADER_SIZE + 5])) {
+ if (nr_commands != be32_to_cpup((__be32 *)&buf->data[TPM_HEADER_SIZE + 5])) {
rc = -EFAULT;
- tpm_buf_destroy(&buf);
goto out;
}
chip->nr_commands = nr_commands;
- attrs = (__be32 *)&buf.data[TPM_HEADER_SIZE + 9];
+ attrs = (__be32 *)&buf->data[TPM_HEADER_SIZE + 9];
for (i = 0; i < nr_commands; i++, attrs++) {
chip->cc_attrs_tbl[i] = be32_to_cpup(attrs);
cc = chip->cc_attrs_tbl[i] & 0xFFFF;
@@ -581,8 +563,6 @@ int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
}
}
- tpm_buf_destroy(&buf);
-
out:
if (rc > 0)
rc = -ENODEV;
@@ -603,20 +583,14 @@ EXPORT_SYMBOL_GPL(tpm2_get_cc_attrs_tbl);
static int tpm2_startup(struct tpm_chip *chip)
{
- struct tpm_buf buf;
- int rc;
-
- dev_info(&chip->dev, "starting up the TPM manually\n");
-
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_STARTUP);
- if (rc < 0)
- return rc;
-
- tpm_buf_append_u16(&buf, TPM2_SU_CLEAR);
- rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to start the TPM");
- tpm_buf_destroy(&buf);
-
- return rc;
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_STARTUP);
+ tpm_buf_append_u16(buf, TPM2_SU_CLEAR);
+ return tpm_transmit_cmd(chip, buf, 0, "TPM2_Startup");
}
/**
diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
index 37570dc088cf..8c9a7e7c82d5 100644
--- a/drivers/char/tpm/tpm2-sessions.c
+++ b/drivers/char/tpm/tpm2-sessions.c
@@ -175,7 +175,6 @@ int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name)
u32 mso = tpm2_handle_mso(handle);
off_t offset = TPM_HEADER_SIZE;
int rc, name_size_alg;
- struct tpm_buf buf;
if (mso != TPM2_MSO_PERSISTENT && mso != TPM2_MSO_VOLATILE &&
mso != TPM2_MSO_NVRAM) {
@@ -183,47 +182,41 @@ int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name)
return sizeof(u32);
}
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_READ_PUBLIC);
- if (rc)
- return rc;
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
- tpm_buf_append_u32(&buf, handle);
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_READ_PUBLIC);
+ tpm_buf_append_u32(buf, handle);
- rc = tpm_transmit_cmd(chip, &buf, 0, "TPM2_ReadPublic");
- if (rc) {
- tpm_buf_destroy(&buf);
+ rc = tpm_transmit_cmd(chip, buf, 0, "TPM2_ReadPublic");
+ if (rc)
return tpm_ret_to_err(rc);
- }
/* Skip TPMT_PUBLIC: */
- offset += tpm_buf_read_u16(&buf, &offset);
+ offset += tpm_buf_read_u16(buf, &offset);
/*
* Ensure space for the length field of TPM2B_NAME and hashAlg field of
* TPMT_HA (the extra four bytes).
*/
- if (offset + 4 > tpm_buf_length(&buf)) {
- tpm_buf_destroy(&buf);
+ if (offset + 4 > tpm_buf_length(buf))
return -EIO;
- }
- rc = tpm_buf_read_u16(&buf, &offset);
- name_size_alg = name_size(&buf.data[offset]);
+ rc = tpm_buf_read_u16(buf, &offset);
+ name_size_alg = name_size(&buf->data[offset]);
if (name_size_alg < 0)
return name_size_alg;
- if (rc != name_size_alg) {
- tpm_buf_destroy(&buf);
+ if (rc != name_size_alg)
return -EIO;
- }
- if (offset + rc > tpm_buf_length(&buf)) {
- tpm_buf_destroy(&buf);
+ if (offset + rc > tpm_buf_length(buf))
return -EIO;
- }
- memcpy(name, &buf.data[offset], rc);
+ memcpy(name, &buf->data[offset], rc);
return name_size_alg;
}
EXPORT_SYMBOL_GPL(tpm2_read_public);
@@ -934,7 +927,6 @@ static int tpm2_load_null(struct tpm_chip *chip, u32 *null_key)
int tpm2_start_auth_session(struct tpm_chip *chip)
{
struct tpm2_auth *auth;
- struct tpm_buf buf;
u32 null_key;
int rc;
@@ -943,6 +935,10 @@ int tpm2_start_auth_session(struct tpm_chip *chip)
return 0;
}
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
auth = kzalloc(sizeof(*auth), GFP_KERNEL);
if (!auth)
return -ENOMEM;
@@ -953,41 +949,37 @@ int tpm2_start_auth_session(struct tpm_chip *chip)
auth->session = TPM_HEADER_SIZE;
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_START_AUTH_SESS);
- if (rc)
- goto out;
-
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_START_AUTH_SESS);
/* salt key handle */
- tpm_buf_append_u32(&buf, null_key);
+ tpm_buf_append_u32(buf, null_key);
/* bind key handle */
- tpm_buf_append_u32(&buf, TPM2_RH_NULL);
+ tpm_buf_append_u32(buf, TPM2_RH_NULL);
/* nonce caller */
get_random_bytes(auth->our_nonce, sizeof(auth->our_nonce));
- tpm_buf_append_u16(&buf, sizeof(auth->our_nonce));
- tpm_buf_append(&buf, auth->our_nonce, sizeof(auth->our_nonce));
+ tpm_buf_append_u16(buf, sizeof(auth->our_nonce));
+ tpm_buf_append(buf, auth->our_nonce, sizeof(auth->our_nonce));
/* append encrypted salt and squirrel away unencrypted in auth */
- tpm_buf_append_salt(&buf, chip, auth);
+ tpm_buf_append_salt(buf, chip, auth);
/* session type (HMAC, audit or policy) */
- tpm_buf_append_u8(&buf, TPM2_SE_HMAC);
+ tpm_buf_append_u8(buf, TPM2_SE_HMAC);
/* symmetric encryption parameters */
/* symmetric algorithm */
- tpm_buf_append_u16(&buf, TPM_ALG_AES);
+ tpm_buf_append_u16(buf, TPM_ALG_AES);
/* bits for symmetric algorithm */
- tpm_buf_append_u16(&buf, AES_KEY_BITS);
+ tpm_buf_append_u16(buf, AES_KEY_BITS);
/* symmetric algorithm mode (must be CFB) */
- tpm_buf_append_u16(&buf, TPM_ALG_CFB);
+ tpm_buf_append_u16(buf, TPM_ALG_CFB);
/* hash algorithm for session */
- tpm_buf_append_u16(&buf, TPM_ALG_SHA256);
+ tpm_buf_append_u16(buf, TPM_ALG_SHA256);
- rc = tpm_ret_to_err(tpm_transmit_cmd(chip, &buf, 0, "StartAuthSession"));
+ rc = tpm_ret_to_err(tpm_transmit_cmd(chip, buf, 0, "TPM2_StartAuthSession"));
tpm2_flush_context(chip, null_key);
if (rc == TPM2_RC_SUCCESS)
- rc = tpm2_parse_start_auth_session(auth, &buf);
-
- tpm_buf_destroy(&buf);
+ rc = tpm2_parse_start_auth_session(auth, buf);
if (rc == TPM2_RC_SUCCESS) {
chip->auth = auth;
@@ -1209,18 +1201,18 @@ static int tpm2_create_primary(struct tpm_chip *chip, u32 hierarchy,
u32 *handle, u8 *name)
{
int rc;
- struct tpm_buf buf;
- struct tpm_buf template;
- rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE_PRIMARY);
- if (rc)
- return rc;
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
- rc = tpm_buf_init_sized(&template);
- if (rc) {
- tpm_buf_destroy(&buf);
- return rc;
- }
+ struct tpm_buf *template __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!template)
+ return -ENOMEM;
+
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE_PRIMARY);
+ tpm_buf_init_sized(template, TPM_BUFSIZE);
/*
* create the template. Note: in order for userspace to
@@ -1232,75 +1224,71 @@ static int tpm2_create_primary(struct tpm_chip *chip, u32 hierarchy,
*/
/* key type */
- tpm_buf_append_u16(&template, TPM_ALG_ECC);
+ tpm_buf_append_u16(template, TPM_ALG_ECC);
/* name algorithm */
- tpm_buf_append_u16(&template, TPM_ALG_SHA256);
+ tpm_buf_append_u16(template, TPM_ALG_SHA256);
/* object properties */
- tpm_buf_append_u32(&template, TPM2_OA_NULL_KEY);
+ tpm_buf_append_u32(template, TPM2_OA_NULL_KEY);
/* sauth policy (empty) */
- tpm_buf_append_u16(&template, 0);
+ tpm_buf_append_u16(template, 0);
/* BEGIN parameters: key specific; for ECC*/
/* symmetric algorithm */
- tpm_buf_append_u16(&template, TPM_ALG_AES);
+ tpm_buf_append_u16(template, TPM_ALG_AES);
/* bits for symmetric algorithm */
- tpm_buf_append_u16(&template, AES_KEY_BITS);
+ tpm_buf_append_u16(template, AES_KEY_BITS);
/* algorithm mode (must be CFB) */
- tpm_buf_append_u16(&template, TPM_ALG_CFB);
+ tpm_buf_append_u16(template, TPM_ALG_CFB);
/* scheme (NULL means any scheme) */
- tpm_buf_append_u16(&template, TPM_ALG_NULL);
+ tpm_buf_append_u16(template, TPM_ALG_NULL);
/* ECC Curve ID */
- tpm_buf_append_u16(&template, TPM2_ECC_NIST_P256);
+ tpm_buf_append_u16(template, TPM2_ECC_NIST_P256);
/* KDF Scheme */
- tpm_buf_append_u16(&template, TPM_ALG_NULL);
+ tpm_buf_append_u16(template, TPM_ALG_NULL);
/* unique: key specific; for ECC it is two zero size points */
- tpm_buf_append_u16(&template, 0);
- tpm_buf_append_u16(&template, 0);
+ tpm_buf_append_u16(template, 0);
+ tpm_buf_append_u16(template, 0);
/* END parameters */
/* primary handle */
- tpm_buf_append_u32(&buf, hierarchy);
- tpm_buf_append_empty_auth(&buf, TPM2_RS_PW);
+ tpm_buf_append_u32(buf, hierarchy);
+ tpm_buf_append_empty_auth(buf, TPM2_RS_PW);
/* sensitive create size is 4 for two empty buffers */
- tpm_buf_append_u16(&buf, 4);
+ tpm_buf_append_u16(buf, 4);
/* sensitive create auth data (empty) */
- tpm_buf_append_u16(&buf, 0);
+ tpm_buf_append_u16(buf, 0);
/* sensitive create sensitive data (empty) */
- tpm_buf_append_u16(&buf, 0);
+ tpm_buf_append_u16(buf, 0);
/* the public template */
- tpm_buf_append(&buf, template.data, template.length);
- tpm_buf_destroy(&template);
+ tpm_buf_append(buf, template->data, template->length);
/* outside info (empty) */
- tpm_buf_append_u16(&buf, 0);
+ tpm_buf_append_u16(buf, 0);
/* creation PCR (none) */
- tpm_buf_append_u32(&buf, 0);
+ tpm_buf_append_u32(buf, 0);
- rc = tpm_transmit_cmd(chip, &buf, 0,
- "attempting to create NULL primary");
+ rc = tpm_transmit_cmd(chip, buf, 0, "TPM2_CreatePrimary");
if (rc == TPM2_RC_SUCCESS)
- rc = tpm2_parse_create_primary(chip, &buf, handle, hierarchy,
+ rc = tpm2_parse_create_primary(chip, buf, handle, hierarchy,
name);
- tpm_buf_destroy(&buf);
-
return rc;
}
diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c
index 60354cd53b5c..cbf86ff5931f 100644
--- a/drivers/char/tpm/tpm2-space.c
+++ b/drivers/char/tpm/tpm2-space.c
@@ -71,24 +71,25 @@ void tpm2_del_space(struct tpm_chip *chip, struct tpm_space *space)
int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
unsigned int *offset, u32 *handle)
{
- struct tpm_buf tbuf;
struct tpm2_context *ctx;
unsigned int body_size;
int rc;
- rc = tpm_buf_init(&tbuf, TPM2_ST_NO_SESSIONS, TPM2_CC_CONTEXT_LOAD);
- if (rc)
- return rc;
+ struct tpm_buf *tbuf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!tbuf)
+ return -ENOMEM;
+
+ tpm_buf_init(tbuf, TPM_BUFSIZE);
+ tpm_buf_reset(tbuf, TPM2_ST_NO_SESSIONS, TPM2_CC_CONTEXT_LOAD);
ctx = (struct tpm2_context *)&buf[*offset];
body_size = sizeof(*ctx) + be16_to_cpu(ctx->blob_size);
- tpm_buf_append(&tbuf, &buf[*offset], body_size);
+ tpm_buf_append(tbuf, &buf[*offset], body_size);
- rc = tpm_transmit_cmd(chip, &tbuf, 4, NULL);
+ rc = tpm_transmit_cmd(chip, tbuf, 4, NULL);
if (rc < 0) {
dev_warn(&chip->dev, "%s: failed with a system error %d\n",
__func__, rc);
- tpm_buf_destroy(&tbuf);
return -EFAULT;
} else if (tpm2_rc_value(rc) == TPM2_RC_HANDLE ||
rc == TPM2_RC_REFERENCE_H0) {
@@ -103,64 +104,55 @@ int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
* flushed outside the space
*/
*handle = 0;
- tpm_buf_destroy(&tbuf);
return -ENOENT;
} else if (tpm2_rc_value(rc) == TPM2_RC_INTEGRITY) {
- tpm_buf_destroy(&tbuf);
return -EINVAL;
} else if (rc > 0) {
dev_warn(&chip->dev, "%s: failed with a TPM error 0x%04X\n",
__func__, rc);
- tpm_buf_destroy(&tbuf);
return -EFAULT;
}
- *handle = be32_to_cpup((__be32 *)&tbuf.data[TPM_HEADER_SIZE]);
+ *handle = be32_to_cpup((__be32 *)&tbuf->data[TPM_HEADER_SIZE]);
*offset += body_size;
-
- tpm_buf_destroy(&tbuf);
return 0;
}
int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf,
unsigned int buf_size, unsigned int *offset)
{
- struct tpm_buf tbuf;
unsigned int body_size;
int rc;
- rc = tpm_buf_init(&tbuf, TPM2_ST_NO_SESSIONS, TPM2_CC_CONTEXT_SAVE);
- if (rc)
- return rc;
+ struct tpm_buf *tbuf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!tbuf)
+ return -ENOMEM;
- tpm_buf_append_u32(&tbuf, handle);
+ tpm_buf_init(tbuf, TPM_BUFSIZE);
+ tpm_buf_reset(tbuf, TPM2_ST_NO_SESSIONS, TPM2_CC_CONTEXT_SAVE);
+ tpm_buf_append_u32(tbuf, handle);
- rc = tpm_transmit_cmd(chip, &tbuf, 0, NULL);
+ rc = tpm_transmit_cmd(chip, tbuf, 0, NULL);
if (rc < 0) {
dev_warn(&chip->dev, "%s: failed with a system error %d\n",
__func__, rc);
- tpm_buf_destroy(&tbuf);
return -EFAULT;
} else if (tpm2_rc_value(rc) == TPM2_RC_REFERENCE_H0) {
- tpm_buf_destroy(&tbuf);
return -ENOENT;
} else if (rc) {
dev_warn(&chip->dev, "%s: failed with a TPM error 0x%04X\n",
__func__, rc);
- tpm_buf_destroy(&tbuf);
return -EFAULT;
}
- body_size = tpm_buf_length(&tbuf) - TPM_HEADER_SIZE;
+ body_size = tpm_buf_length(tbuf) - TPM_HEADER_SIZE;
if ((*offset + body_size) > buf_size) {
dev_warn(&chip->dev, "%s: out of backing storage\n", __func__);
- tpm_buf_destroy(&tbuf);
return -ENOMEM;
}
- memcpy(&buf[*offset], &tbuf.data[TPM_HEADER_SIZE], body_size);
+ memcpy(&buf[*offset], &tbuf->data[TPM_HEADER_SIZE], body_size);
*offset += body_size;
- tpm_buf_destroy(&tbuf);
return 0;
}
diff --git a/drivers/char/tpm/tpm_vtpm_proxy.c b/drivers/char/tpm/tpm_vtpm_proxy.c
index 0818bb517805..682dfc93845d 100644
--- a/drivers/char/tpm/tpm_vtpm_proxy.c
+++ b/drivers/char/tpm/tpm_vtpm_proxy.c
@@ -395,40 +395,36 @@ static bool vtpm_proxy_tpm_req_canceled(struct tpm_chip *chip, u8 status)
static int vtpm_proxy_request_locality(struct tpm_chip *chip, int locality)
{
- struct tpm_buf buf;
int rc;
const struct tpm_header *header;
struct proxy_dev *proxy_dev = dev_get_drvdata(&chip->dev);
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ tpm_buf_init(buf, TPM_BUFSIZE);
if (chip->flags & TPM_CHIP_FLAG_TPM2)
- rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS,
- TPM2_CC_SET_LOCALITY);
+ tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_SET_LOCALITY);
else
- rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND,
- TPM_ORD_SET_LOCALITY);
- if (rc)
- return rc;
- tpm_buf_append_u8(&buf, locality);
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_SET_LOCALITY);
+
+ tpm_buf_append_u8(buf, locality);
proxy_dev->state |= STATE_DRIVER_COMMAND;
- rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to set locality");
+ rc = tpm_transmit_cmd(chip, buf, 0, "attempting to set locality");
proxy_dev->state &= ~STATE_DRIVER_COMMAND;
- if (rc < 0) {
- locality = rc;
- goto out;
- }
+ if (rc < 0)
+ return rc;
- header = (const struct tpm_header *)buf.data;
+ header = (const struct tpm_header *)buf->data;
rc = be32_to_cpu(header->return_code);
if (rc)
locality = -1;
-out:
- tpm_buf_destroy(&buf);
-
return locality;
}
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 8470ad6dd090..24b1d253e7f5 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -25,7 +25,8 @@
#include <crypto/hash_info.h>
#include <crypto/aes.h>
-#define TPM_DIGEST_SIZE 20 /* Max TPM v1.2 PCR size */
+#define TPM_DIGEST_SIZE 20 /* Max TPM v1.2 PCR size */
+#define TPM_BUFSIZE 4096
/*
* SHA-512 is, as of today, the largest digest in the TCG algorithm repository.
@@ -389,13 +390,15 @@ enum tpm_buf_flags {
};
/*
- * A string buffer type for constructing TPM commands.
+ * A buffer for constructing and parsing TPM commands, responses and sized
+ * (TPM2B) buffers.
*/
struct tpm_buf {
- u32 flags;
- u32 length;
- u8 *data;
+ u8 flags;
u8 handles;
+ u16 length;
+ u16 capacity;
+ u8 data[];
};
enum tpm2_object_attributes {
@@ -426,12 +429,11 @@ struct tpm2_hash {
unsigned int tpm_id;
};
-int tpm_buf_init(struct tpm_buf *buf, u16 tag, u32 ordinal);
+void tpm_buf_init(struct tpm_buf *buf, u16 buf_size);
+void tpm_buf_init_sized(struct tpm_buf *buf, u16 buf_size);
void tpm_buf_reset(struct tpm_buf *buf, u16 tag, u32 ordinal);
-int tpm_buf_init_sized(struct tpm_buf *buf);
void tpm_buf_reset_sized(struct tpm_buf *buf);
-void tpm_buf_destroy(struct tpm_buf *buf);
-u32 tpm_buf_length(struct tpm_buf *buf);
+u16 tpm_buf_length(struct tpm_buf *buf);
void tpm_buf_append(struct tpm_buf *buf, const u8 *new_data, u16 new_length);
void tpm_buf_append_u8(struct tpm_buf *buf, const u8 value);
void tpm_buf_append_u16(struct tpm_buf *buf, const u16 value);
diff --git a/security/keys/trusted-keys/trusted_tpm1.c b/security/keys/trusted-keys/trusted_tpm1.c
index 5b5f7a029bc3..f36f6a0b533f 100644
--- a/security/keys/trusted-keys/trusted_tpm1.c
+++ b/security/keys/trusted-keys/trusted_tpm1.c
@@ -310,9 +310,10 @@ static int TSS_checkhmac2(unsigned char *buffer,
* For key specific tpm requests, we will generate and send our
* own TPM command packets using the drivers send function.
*/
-static int trusted_tpm_send(unsigned char *cmd, size_t buflen)
+static int trusted_tpm_send(void *cmd, size_t cmd_len)
{
- struct tpm_buf buf;
+ u8 buf_data[512];
+ struct tpm_buf *buf = (struct tpm_buf *)buf_data;
int rc;
if (!chip)
@@ -322,11 +323,10 @@ static int trusted_tpm_send(unsigned char *cmd, size_t buflen)
if (rc)
return rc;
- buf.flags = 0;
- buf.length = buflen;
- buf.data = cmd;
+ tpm_buf_init(buf, sizeof(buf_data));
+ tpm_buf_append(buf, cmd, cmd_len);
dump_tpm_buf(cmd);
- rc = tpm_transmit_cmd(chip, &buf, 4, "sending data");
+ rc = tpm_transmit_cmd(chip, buf, 4, "sending data");
dump_tpm_buf(cmd);
if (rc > 0)
@@ -624,23 +624,23 @@ static int tpm_unseal(struct tpm_buf *tb,
static int key_seal(struct trusted_key_payload *p,
struct trusted_key_options *o)
{
- struct tpm_buf tb;
int ret;
- ret = tpm_buf_init(&tb, 0, 0);
- if (ret)
- return ret;
+ struct tpm_buf *tb __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!tb)
+ return -ENOMEM;
+
+ tpm_buf_init(tb, TPM_BUFSIZE);
/* include migratable flag at end of sealed key */
p->key[p->key_len] = p->migratable;
- ret = tpm_seal(&tb, o->keytype, o->keyhandle, o->keyauth,
+ ret = tpm_seal(tb, o->keytype, o->keyhandle, o->keyauth,
p->key, p->key_len + 1, p->blob, &p->blob_len,
o->blobauth, o->pcrinfo, o->pcrinfo_len);
if (ret < 0)
pr_info("srkseal failed (%d)\n", ret);
- tpm_buf_destroy(&tb);
return ret;
}
@@ -650,14 +650,15 @@ static int key_seal(struct trusted_key_payload *p,
static int key_unseal(struct trusted_key_payload *p,
struct trusted_key_options *o)
{
- struct tpm_buf tb;
int ret;
- ret = tpm_buf_init(&tb, 0, 0);
- if (ret)
- return ret;
+ struct tpm_buf *tb __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!tb)
+ return -ENOMEM;
+
+ tpm_buf_init(tb, TPM_BUFSIZE);
- ret = tpm_unseal(&tb, o->keyhandle, o->keyauth, p->blob, p->blob_len,
+ ret = tpm_unseal(tb, o->keyhandle, o->keyauth, p->blob, p->blob_len,
o->blobauth, p->key, &p->key_len);
if (ret < 0)
pr_info("srkunseal failed (%d)\n", ret);
@@ -665,7 +666,6 @@ static int key_unseal(struct trusted_key_payload *p,
/* pull migratable flag out of sealed key */
p->migratable = p->key[--p->key_len];
- tpm_buf_destroy(&tb);
return ret;
}
diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
index 6fcff1066873..4d8d8705cbbc 100644
--- a/security/keys/trusted-keys/trusted_tpm2.c
+++ b/security/keys/trusted-keys/trusted_tpm2.c
@@ -205,7 +205,6 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
{
u8 parent_name[TPM2_MAX_NAME_SIZE];
off_t offset = TPM_HEADER_SIZE;
- struct tpm_buf buf, sized;
u16 parent_name_size;
int blob_len = 0;
int hash;
@@ -233,98 +232,100 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
if (rc)
goto out_put;
- rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
- if (rc) {
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf) {
+ rc = -ENOMEM;
tpm2_end_auth_session(chip);
goto out_put;
}
- rc = tpm_buf_init_sized(&sized);
- if (rc) {
- tpm_buf_destroy(&buf);
- tpm2_end_auth_session(chip);
- goto out_put;
- }
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
- rc = tpm_buf_append_name(chip, &buf, options->keyhandle, parent_name,
+ rc = tpm_buf_append_name(chip, buf, options->keyhandle, parent_name,
parent_name_size);
if (rc)
- goto out;
+ goto out_put;
- tpm_buf_append_hmac_session(chip, &buf, TPM2_SA_DECRYPT,
+ tpm_buf_append_hmac_session(chip, buf, TPM2_SA_DECRYPT,
options->keyauth, TPM_DIGEST_SIZE);
+ struct tpm_buf *sized __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!sized) {
+ rc = -ENOMEM;
+ tpm2_end_auth_session(chip);
+ goto out_put;
+ }
+
/* sensitive */
- tpm_buf_append_u16(&sized, options->blobauth_len);
+ tpm_buf_init_sized(sized, TPM_BUFSIZE);
+ tpm_buf_append_u16(sized, options->blobauth_len);
if (options->blobauth_len)
- tpm_buf_append(&sized, options->blobauth, options->blobauth_len);
+ tpm_buf_append(sized, options->blobauth, options->blobauth_len);
- tpm_buf_append_u16(&sized, payload->key_len);
- tpm_buf_append(&sized, payload->key, payload->key_len);
- tpm_buf_append(&buf, sized.data, sized.length);
+ tpm_buf_append_u16(sized, payload->key_len);
+ tpm_buf_append(sized, payload->key, payload->key_len);
+ tpm_buf_append(buf, sized->data, sized->length);
/* public */
- tpm_buf_reset_sized(&sized);
- tpm_buf_append_u16(&sized, TPM_ALG_KEYEDHASH);
- tpm_buf_append_u16(&sized, hash);
+ tpm_buf_init_sized(sized, TPM_BUFSIZE);
+ tpm_buf_append_u16(sized, TPM_ALG_KEYEDHASH);
+ tpm_buf_append_u16(sized, hash);
/* key properties */
flags = 0;
flags |= options->policydigest_len ? 0 : TPM2_OA_USER_WITH_AUTH;
flags |= payload->migratable ? 0 : (TPM2_OA_FIXED_TPM | TPM2_OA_FIXED_PARENT);
- tpm_buf_append_u32(&sized, flags);
+ tpm_buf_append_u32(sized, flags);
/* policy */
- tpm_buf_append_u16(&sized, options->policydigest_len);
+ tpm_buf_append_u16(sized, options->policydigest_len);
if (options->policydigest_len)
- tpm_buf_append(&sized, options->policydigest, options->policydigest_len);
+ tpm_buf_append(sized, options->policydigest, options->policydigest_len);
/* public parameters */
- tpm_buf_append_u16(&sized, TPM_ALG_NULL);
- tpm_buf_append_u16(&sized, 0);
+ tpm_buf_append_u16(sized, TPM_ALG_NULL);
+ tpm_buf_append_u16(sized, 0);
- tpm_buf_append(&buf, sized.data, sized.length);
+ tpm_buf_append(buf, sized->data, sized->length);
/* outside info */
- tpm_buf_append_u16(&buf, 0);
+ tpm_buf_append_u16(buf, 0);
/* creation PCR */
- tpm_buf_append_u32(&buf, 0);
+ tpm_buf_append_u32(buf, 0);
- if (buf.flags & TPM_BUF_INVALID) {
+ if (buf->flags & TPM_BUF_INVALID) {
rc = -E2BIG;
tpm2_end_auth_session(chip);
goto out;
}
- rc = tpm_buf_fill_hmac_session(chip, &buf);
+ rc = tpm_buf_fill_hmac_session(chip, buf);
if (rc)
goto out;
- rc = tpm_transmit_cmd(chip, &buf, 4, "sealing data");
- rc = tpm_buf_check_hmac_response(chip, &buf, rc);
+ rc = tpm_transmit_cmd(chip, buf, 4, "sealing data");
+ rc = tpm_buf_check_hmac_response(chip, buf, rc);
if (rc)
goto out;
- blob_len = tpm_buf_read_u32(&buf, &offset);
- if (blob_len > MAX_BLOB_SIZE || buf.flags & TPM_BUF_INVALID) {
+ blob_len = tpm_buf_read_u32(buf, &offset);
+ if (blob_len > MAX_BLOB_SIZE || buf->flags & TPM_BUF_INVALID) {
rc = -E2BIG;
goto out;
}
- if (buf.length - offset < blob_len) {
+ if (buf->length - offset < blob_len) {
rc = -EFAULT;
goto out;
}
- blob_len = tpm2_key_encode(payload, options, &buf.data[offset], blob_len);
+ blob_len = tpm2_key_encode(payload, options, &buf->data[offset], blob_len);
if (blob_len < 0)
rc = blob_len;
out:
- tpm_buf_destroy(&sized);
- tpm_buf_destroy(&buf);
-
if (!rc)
payload->blob_len = blob_len;
@@ -356,7 +357,6 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
u32 *blob_handle)
{
u8 *blob_ref __free(kfree) = NULL;
- struct tpm_buf buf;
unsigned int private_len;
unsigned int public_len;
unsigned int blob_len;
@@ -396,40 +396,39 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
if (rc)
return rc;
- rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
- if (rc) {
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf) {
tpm2_end_auth_session(chip);
- return rc;
+ return -ENOMEM;
}
- rc = tpm_buf_append_name(chip, &buf, options->keyhandle, parent_name,
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
+
+ rc = tpm_buf_append_name(chip, buf, options->keyhandle, parent_name,
parent_name_size);
if (rc)
- goto out;
+ return rc;
- tpm_buf_append_hmac_session(chip, &buf, 0, options->keyauth,
+ tpm_buf_append_hmac_session(chip, buf, 0, options->keyauth,
TPM_DIGEST_SIZE);
- tpm_buf_append(&buf, blob, blob_len);
+ tpm_buf_append(buf, blob, blob_len);
- if (buf.flags & TPM_BUF_INVALID) {
- rc = -E2BIG;
+ if (buf->flags & TPM_BUF_INVALID) {
tpm2_end_auth_session(chip);
- goto out;
+ return -E2BIG;
}
- rc = tpm_buf_fill_hmac_session(chip, &buf);
+ rc = tpm_buf_fill_hmac_session(chip, buf);
if (rc)
- goto out;
+ return rc;
- rc = tpm_transmit_cmd(chip, &buf, 4, "loading blob");
- rc = tpm_buf_check_hmac_response(chip, &buf, rc);
+ rc = tpm_transmit_cmd(chip, buf, 4, "loading blob");
+ rc = tpm_buf_check_hmac_response(chip, buf, rc);
if (!rc)
*blob_handle = be32_to_cpup(
- (__be32 *) &buf.data[TPM_HEADER_SIZE]);
-
-out:
- tpm_buf_destroy(&buf);
+ (__be32 *)&buf->data[TPM_HEADER_SIZE]);
return tpm_ret_to_err(rc);
}
@@ -454,28 +453,28 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
u16 parent_name_size,
u32 blob_handle)
{
- struct tpm_buf buf;
u16 data_len;
u8 *data;
int rc;
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
rc = tpm2_start_auth_session(chip);
if (rc)
return rc;
- rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
- if (rc) {
- tpm2_end_auth_session(chip);
- return rc;
- }
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
- rc = tpm_buf_append_name(chip, &buf, options->keyhandle, parent_name,
+ rc = tpm_buf_append_name(chip, buf, options->keyhandle, parent_name,
parent_name_size);
if (rc)
- goto out;
+ return rc;
if (!options->policyhandle) {
- tpm_buf_append_hmac_session(chip, &buf, TPM2_SA_ENCRYPT,
+ tpm_buf_append_hmac_session(chip, buf, TPM2_SA_ENCRYPT,
options->blobauth,
options->blobauth_len);
} else {
@@ -490,37 +489,33 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
* could repeat our actions with the exfiltrated
* password.
*/
- tpm_buf_append_u32(&buf, 9 + options->blobauth_len);
- tpm_buf_append_u32(&buf, options->policyhandle);
- tpm_buf_append_u16(&buf, 0);
- tpm_buf_append_u8(&buf, 0);
- tpm_buf_append_u16(&buf, options->blobauth_len);
- tpm_buf_append(&buf, options->blobauth, options->blobauth_len);
+ tpm_buf_append_u32(buf, 9 + options->blobauth_len);
+ tpm_buf_append_u32(buf, options->policyhandle);
+ tpm_buf_append_u16(buf, 0);
+ tpm_buf_append_u8(buf, 0);
+ tpm_buf_append_u16(buf, options->blobauth_len);
+ tpm_buf_append(buf, options->blobauth, options->blobauth_len);
if (tpm2_chip_auth(chip))
- tpm_buf_append_hmac_session(chip, &buf, TPM2_SA_ENCRYPT, NULL, 0);
+ tpm_buf_append_hmac_session(chip, buf, TPM2_SA_ENCRYPT, NULL, 0);
}
- rc = tpm_buf_fill_hmac_session(chip, &buf);
+ rc = tpm_buf_fill_hmac_session(chip, buf);
if (rc)
- goto out;
+ return rc;
- rc = tpm_transmit_cmd(chip, &buf, 6, "unsealing");
- rc = tpm_buf_check_hmac_response(chip, &buf, rc);
+ rc = tpm_transmit_cmd(chip, buf, 6, "unsealing");
+ rc = tpm_buf_check_hmac_response(chip, buf, rc);
if (!rc) {
data_len = be16_to_cpup(
- (__be16 *) &buf.data[TPM_HEADER_SIZE + 4]);
- if (data_len < MIN_KEY_SIZE || data_len > MAX_KEY_SIZE) {
- rc = -EFAULT;
- goto out;
- }
+ (__be16 *)&buf->data[TPM_HEADER_SIZE + 4]);
+ if (data_len < MIN_KEY_SIZE || data_len > MAX_KEY_SIZE)
+ return -EFAULT;
- if (tpm_buf_length(&buf) < TPM_HEADER_SIZE + 6 + data_len) {
- rc = -EFAULT;
- goto out;
- }
- data = &buf.data[TPM_HEADER_SIZE + 6];
+ if (tpm_buf_length(buf) < TPM_HEADER_SIZE + 6 + data_len)
+ return -EFAULT;
+ data = &buf->data[TPM_HEADER_SIZE + 6];
if (payload->old_format) {
/* migratable flag is at the end of the key */
@@ -537,8 +532,6 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
}
}
-out:
- tpm_buf_destroy(&buf);
return tpm_ret_to_err(rc);
}
--
2.39.5
^ permalink raw reply related
* [PATCH v6 09/11] tpm-buf: Merge TPM_BUF_BOUNDARY_ERROR and TPM_BUF_OVERFLOW
From: Jarkko Sakkinen @ 2025-12-14 15:38 UTC (permalink / raw)
To: linux-integrity
Cc: Ross Philipson, Jarkko Sakkinen, Jonathan McDowell, Peter Huewe,
Jarkko Sakkinen, Jason Gunthorpe, David Howells, Paul Moore,
James Morris, Serge E. Hallyn, James Bottomley, Mimi Zohar,
open list, open list:KEYS/KEYRINGS, open list:SECURITY SUBSYSTEM
In-Reply-To: <20251214153808.73831-1-jarkko@kernel.org>
From: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
Merge TPM_BUF_BOUNDARY_ERROR and TPM_BUF_OVERFLOW into TPM_BUF_INVALID,
given that they are identical. The only difference are the log messages.
In addition, add a missing TPM_BUF_INVALID check to tpm_buf_append_handle()
following the pattern from other functions in tpm-buf.c.
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
Reviewed-by: Jonathan McDowell <noodles@meta.com>
---
drivers/char/tpm/tpm-buf.c | 14 ++++++++------
include/linux/tpm.h | 8 +++-----
security/keys/trusted-keys/trusted_tpm2.c | 6 +++---
3 files changed, 14 insertions(+), 14 deletions(-)
diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c
index dc882fc9fa9e..69ee77400539 100644
--- a/drivers/char/tpm/tpm-buf.c
+++ b/drivers/char/tpm/tpm-buf.c
@@ -104,13 +104,12 @@ EXPORT_SYMBOL_GPL(tpm_buf_length);
*/
void tpm_buf_append(struct tpm_buf *buf, const u8 *new_data, u16 new_length)
{
- /* Return silently if overflow has already happened. */
- if (buf->flags & TPM_BUF_OVERFLOW)
+ if (buf->flags & TPM_BUF_INVALID)
return;
if ((buf->length + new_length) > PAGE_SIZE) {
WARN(1, "tpm_buf: write overflow\n");
- buf->flags |= TPM_BUF_OVERFLOW;
+ buf->flags |= TPM_BUF_INVALID;
return;
}
@@ -157,8 +156,12 @@ EXPORT_SYMBOL_GPL(tpm_buf_append_u32);
*/
void tpm_buf_append_handle(struct tpm_chip *chip, struct tpm_buf *buf, u32 handle)
{
+ if (buf->flags & TPM_BUF_INVALID)
+ return;
+
if (buf->flags & TPM_BUF_TPM2B) {
dev_err(&chip->dev, "Invalid buffer type (TPM2B)\n");
+ buf->flags |= TPM_BUF_INVALID;
return;
}
@@ -177,14 +180,13 @@ static void tpm_buf_read(struct tpm_buf *buf, off_t *offset, size_t count, void
{
off_t next_offset;
- /* Return silently if overflow has already happened. */
- if (buf->flags & TPM_BUF_BOUNDARY_ERROR)
+ if (buf->flags & TPM_BUF_INVALID)
return;
next_offset = *offset + count;
if (next_offset > buf->length) {
WARN(1, "tpm_buf: read out of boundary\n");
- buf->flags |= TPM_BUF_BOUNDARY_ERROR;
+ buf->flags |= TPM_BUF_INVALID;
return;
}
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index d710a3aea2ff..8470ad6dd090 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -382,12 +382,10 @@ struct tpm_header {
} __packed;
enum tpm_buf_flags {
- /* the capacity exceeded: */
- TPM_BUF_OVERFLOW = BIT(0),
/* TPM2B format: */
- TPM_BUF_TPM2B = BIT(1),
- /* read out of boundary: */
- TPM_BUF_BOUNDARY_ERROR = BIT(2),
+ TPM_BUF_TPM2B = BIT(0),
+ /* The buffer is in invalid and unusable state: */
+ TPM_BUF_INVALID = BIT(1),
};
/*
diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
index 3de84b30b655..6fcff1066873 100644
--- a/security/keys/trusted-keys/trusted_tpm2.c
+++ b/security/keys/trusted-keys/trusted_tpm2.c
@@ -292,7 +292,7 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
/* creation PCR */
tpm_buf_append_u32(&buf, 0);
- if (buf.flags & TPM_BUF_OVERFLOW) {
+ if (buf.flags & TPM_BUF_INVALID) {
rc = -E2BIG;
tpm2_end_auth_session(chip);
goto out;
@@ -308,7 +308,7 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
goto out;
blob_len = tpm_buf_read_u32(&buf, &offset);
- if (blob_len > MAX_BLOB_SIZE || buf.flags & TPM_BUF_BOUNDARY_ERROR) {
+ if (blob_len > MAX_BLOB_SIZE || buf.flags & TPM_BUF_INVALID) {
rc = -E2BIG;
goto out;
}
@@ -412,7 +412,7 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
tpm_buf_append(&buf, blob, blob_len);
- if (buf.flags & TPM_BUF_OVERFLOW) {
+ if (buf.flags & TPM_BUF_INVALID) {
rc = -E2BIG;
tpm2_end_auth_session(chip);
goto out;
--
2.39.5
^ permalink raw reply related
* [PATCH v6 08/11] tpm: In tpm_get_random() replace 'retries' with a zero check
From: Jarkko Sakkinen @ 2025-12-14 15:38 UTC (permalink / raw)
To: linux-integrity
Cc: Ross Philipson, Jarkko Sakkinen, Peter Huewe, Jason Gunthorpe,
David Howells, Paul Moore, James Morris, Serge E. Hallyn,
open list, open list:KEYS/KEYRINGS, open list:SECURITY SUBSYSTEM
In-Reply-To: <20251214153808.73831-1-jarkko@kernel.org>
Check for zero byte read instead of having retries counter in order to make
wait flag properly enforcing. Progress is still guaranteed given the zero
check and iterations are capped up to TPM_MAX_RNG_DATA iterations at most
(as per theoretical limit).
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
drivers/char/tpm/tpm-interface.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 0a79ed3696b7..021553e8a314 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -630,7 +630,6 @@ int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max, bool wait)
{
u32 num_bytes = max;
u8 *out_ptr = out;
- int retries = 5;
int total = 0;
int rc;
@@ -656,8 +655,12 @@ int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max, bool wait)
else
rc = tpm1_get_random(chip, out_ptr, num_bytes);
- if (rc < 0)
+ if (rc <= 0) {
+ if (!rc)
+ rc = -EIO;
+
goto err;
+ }
if (!wait) {
total = rc;
@@ -667,7 +670,7 @@ int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max, bool wait)
out_ptr += rc;
total += rc;
num_bytes -= rc;
- } while (retries-- && total < max);
+ } while (total < max);
tpm_put_ops(chip);
return total ? total : -EIO;
--
2.39.5
^ permalink raw reply related
* [PATCH v6 07/11] tpm: Send only one at most TPM2_GetRandom command
From: Jarkko Sakkinen @ 2025-12-14 15:38 UTC (permalink / raw)
To: linux-integrity
Cc: Ross Philipson, Jarkko Sakkinen, David S . Miller, Herbert Xu,
Peter Huewe, Jason Gunthorpe, David Howells, Paul Moore,
James Morris, Serge E. Hallyn, James Bottomley, Mimi Zohar,
open list, open list:KEYS/KEYRINGS, open list:SECURITY SUBSYSTEM
In-Reply-To: <20251214153808.73831-1-jarkko@kernel.org>
hwrng framework does not have a requirement that the all bytes requested
need to be provided. By enforcing such a requirement internally, TPM driver
can cause unpredictability in latency, as a single tpm_get_random() call
can result multiple TPM commands.
Especially, when TCG_TPM2_HMAC is enabled, extra roundtrips could have
significant effect to the system latency.
Add a wait-parameter to enforce the old behavior and set it to true only at
the call sites for TPM 1.2 keys. At the call sites of hwrng, set @wait to
false.
Cc: David S. Miller <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
v4:
- Fixed grammar mistakes.
---
drivers/char/tpm/tpm-chip.c | 2 +-
drivers/char/tpm/tpm-interface.c | 11 +++++++++--
include/linux/tpm.h | 2 +-
security/keys/trusted-keys/trusted_tpm1.c | 8 ++++----
4 files changed, 15 insertions(+), 8 deletions(-)
diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index 082b910ddf0d..8fca4373e2df 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -494,7 +494,7 @@ static int tpm_hwrng_read(struct hwrng *rng, void *data, size_t max, bool wait)
{
struct tpm_chip *chip = container_of(rng, struct tpm_chip, hwrng);
- return tpm_get_random(chip, data, max);
+ return tpm_get_random(chip, data, max, false);
}
static bool tpm_is_hwrng_enabled(struct tpm_chip *chip)
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index d157be738612..0a79ed3696b7 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -614,9 +614,11 @@ static int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
* @chip: A &tpm_chip instance. Whenset to %NULL, the default chip is used.
* @out: Destination buffer for the acquired random bytes.
* @max: The maximum number of bytes to write to @out.
+ * @wait: Set to true when all of the @max bytes need to be acquired.
*
* Iterates pulling more bytes from TPM up until all of the @max bytes have been
- * received.
+ * received, when @wait it sets true. Otherwise, the queries for @max bytes from
+ * TPM exactly once, and returns the bytes that were received.
*
* Returns the number of random bytes read on success.
* Returns -EINVAL when @out is NULL, or @max is not between zero and
@@ -624,7 +626,7 @@ static int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
* Returns tpm_transmit_cmd() error codes when the TPM command results an
* error.
*/
-int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max)
+int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max, bool wait)
{
u32 num_bytes = max;
u8 *out_ptr = out;
@@ -657,6 +659,11 @@ int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max)
if (rc < 0)
goto err;
+ if (!wait) {
+ total = rc;
+ break;
+ }
+
out_ptr += rc;
total += rc;
num_bytes -= rc;
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 72610f1aa402..d710a3aea2ff 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -487,7 +487,7 @@ extern int tpm_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
struct tpm_digest *digest);
extern int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
struct tpm_digest *digests);
-extern int tpm_get_random(struct tpm_chip *chip, u8 *data, size_t max);
+int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max, bool wait);
extern struct tpm_chip *tpm_default_chip(void);
void tpm2_flush_context(struct tpm_chip *chip, u32 handle);
int tpm2_find_hash_alg(unsigned int crypto_id);
diff --git a/security/keys/trusted-keys/trusted_tpm1.c b/security/keys/trusted-keys/trusted_tpm1.c
index 636acb66a4f6..5b5f7a029bc3 100644
--- a/security/keys/trusted-keys/trusted_tpm1.c
+++ b/security/keys/trusted-keys/trusted_tpm1.c
@@ -361,7 +361,7 @@ static int osap(struct tpm_buf *tb, struct osapsess *s,
unsigned char ononce[TPM_NONCE_SIZE];
int ret;
- ret = tpm_get_random(chip, ononce, TPM_NONCE_SIZE);
+ ret = tpm_get_random(chip, ononce, TPM_NONCE_SIZE, true);
if (ret < 0)
return ret;
@@ -454,7 +454,7 @@ static int tpm_seal(struct tpm_buf *tb, uint16_t keytype,
memcpy(td->xorwork + SHA1_DIGEST_SIZE, sess.enonce, SHA1_DIGEST_SIZE);
sha1(td->xorwork, SHA1_DIGEST_SIZE * 2, td->xorhash);
- ret = tpm_get_random(chip, td->nonceodd, TPM_NONCE_SIZE);
+ ret = tpm_get_random(chip, td->nonceodd, TPM_NONCE_SIZE, true);
if (ret < 0)
goto out;
@@ -565,7 +565,7 @@ static int tpm_unseal(struct tpm_buf *tb,
}
ordinal = htonl(TPM_ORD_UNSEAL);
- ret = tpm_get_random(chip, nonceodd, TPM_NONCE_SIZE);
+ ret = tpm_get_random(chip, nonceodd, TPM_NONCE_SIZE, true);
if (ret < 0)
return ret;
@@ -938,7 +938,7 @@ static int trusted_tpm_unseal(struct trusted_key_payload *p, char *datablob)
static int trusted_tpm_get_random(unsigned char *key, size_t key_len)
{
- return tpm_get_random(chip, key, key_len);
+ return tpm_get_random(chip, key, key_len, true);
}
static int __init init_digests(void)
--
2.39.5
^ permalink raw reply related
* [PATCH v6 06/11] tpm: Orchestrate TPM commands in tpm_get_random()
From: Jarkko Sakkinen @ 2025-12-14 15:38 UTC (permalink / raw)
To: linux-integrity
Cc: Ross Philipson, Jarkko Sakkinen, Peter Huewe, Jason Gunthorpe,
David Howells, Paul Moore, James Morris, Serge E. Hallyn,
open list, open list:KEYS/KEYRINGS, open list:SECURITY SUBSYSTEM
In-Reply-To: <20251214153808.73831-1-jarkko@kernel.org>
tpm1_get_random() and tpm2_get_random() contain duplicate orchestration
code. Consolidate orchestration to tpm_get_random().
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
drivers/char/tpm/tpm-interface.c | 175 +++++++++++++++++++++++++++++--
drivers/char/tpm/tpm.h | 2 -
drivers/char/tpm/tpm1-cmd.c | 69 ------------
drivers/char/tpm/tpm2-cmd.c | 104 ------------------
4 files changed, 164 insertions(+), 186 deletions(-)
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index f745a098908b..d157be738612 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -26,7 +26,7 @@
#include <linux/suspend.h>
#include <linux/freezer.h>
#include <linux/tpm_eventlog.h>
-
+#include <linux/tpm_command.h>
#include "tpm.h"
/*
@@ -486,19 +486,153 @@ int tpm_pm_resume(struct device *dev)
}
EXPORT_SYMBOL_GPL(tpm_pm_resume);
+struct tpm1_get_random_out {
+ __be32 rng_data_len;
+ u8 rng_data[TPM_MAX_RNG_DATA];
+} __packed;
+
+static int tpm1_get_random(struct tpm_chip *chip, u8 *out, size_t max)
+{
+ struct tpm1_get_random_out *resp;
+ struct tpm_buf buf;
+ u32 recd;
+ int rc;
+
+ if (!out || !max || max > TPM_MAX_RNG_DATA)
+ return -EINVAL;
+
+ rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GETRANDOM);
+ if (rc)
+ return rc;
+
+ tpm_buf_append_u32(&buf, max);
+
+ rc = tpm_transmit_cmd(chip, &buf, sizeof(resp->rng_data_len), "TPM_GetRandom");
+ if (rc) {
+ if (rc > 0)
+ rc = -EIO;
+ goto err;
+ }
+
+ resp = (struct tpm1_get_random_out *)&buf.data[TPM_HEADER_SIZE];
+
+ recd = be32_to_cpu(resp->rng_data_len);
+ if (recd > max) {
+ rc = -EIO;
+ goto err;
+ }
+
+ if (buf.length < TPM_HEADER_SIZE + sizeof(resp->rng_data_len) + recd) {
+ rc = -EIO;
+ goto err;
+ }
+
+ memcpy(out, resp->rng_data, recd);
+ tpm_buf_destroy(&buf);
+ return recd;
+
+err:
+ tpm_buf_destroy(&buf);
+ return rc;
+}
+
+struct tpm2_get_random_out {
+ __be16 size;
+ u8 buffer[TPM_MAX_RNG_DATA];
+} __packed;
+
+static int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
+{
+ struct tpm2_get_random_out *resp;
+ struct tpm_header *head;
+ struct tpm_buf buf;
+ off_t offset;
+ u32 recd;
+ int ret;
+
+ if (!out || !max || max > TPM_MAX_RNG_DATA)
+ return -EINVAL;
+
+ ret = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_GET_RANDOM);
+ if (ret)
+ return ret;
+
+ if (tpm2_chip_auth(chip)) {
+ tpm_buf_append_hmac_session(chip, &buf,
+ TPM2_SA_ENCRYPT | TPM2_SA_CONTINUE_SESSION,
+ NULL, 0);
+ } else {
+ head = (struct tpm_header *)buf.data;
+ head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
+ }
+ tpm_buf_append_u16(&buf, max);
+
+ ret = tpm_buf_fill_hmac_session(chip, &buf);
+ if (ret) {
+ tpm_buf_destroy(&buf);
+ return ret;
+ }
+
+ ret = tpm_transmit_cmd(chip, &buf, offsetof(struct tpm2_get_random_out, buffer),
+ "TPM2_GetRandom");
+
+ ret = tpm_buf_check_hmac_response(chip, &buf, ret);
+ if (ret) {
+ if (ret > 0)
+ ret = -EIO;
+
+ goto out;
+ }
+
+ head = (struct tpm_header *)buf.data;
+ offset = TPM_HEADER_SIZE;
+
+ /* Skip the parameter size field: */
+ if (be16_to_cpu(head->tag) == TPM2_ST_SESSIONS)
+ offset += 4;
+
+ resp = (struct tpm2_get_random_out *)&buf.data[offset];
+ recd = min_t(u32, be16_to_cpu(resp->size), max);
+
+ if (tpm_buf_length(&buf) <
+ TPM_HEADER_SIZE + offsetof(struct tpm2_get_random_out, buffer) + recd) {
+ ret = -EIO;
+ goto out;
+ }
+
+ memcpy(out, resp->buffer, recd);
+ return recd;
+
+out:
+ tpm2_end_auth_session(chip);
+ tpm_buf_destroy(&buf);
+ return ret;
+}
+
/**
- * tpm_get_random() - get random bytes from the TPM's RNG
- * @chip: a &struct tpm_chip instance, %NULL for the default chip
- * @out: destination buffer for the random bytes
- * @max: the max number of bytes to write to @out
+ * tpm_get_random() - Get random bytes from the TPM's RNG
+ * @chip: A &tpm_chip instance. Whenset to %NULL, the default chip is used.
+ * @out: Destination buffer for the acquired random bytes.
+ * @max: The maximum number of bytes to write to @out.
+ *
+ * Iterates pulling more bytes from TPM up until all of the @max bytes have been
+ * received.
*
- * Return: number of random bytes read or a negative error value.
+ * Returns the number of random bytes read on success.
+ * Returns -EINVAL when @out is NULL, or @max is not between zero and
+ * %TPM_MAX_RNG_DATA.
+ * Returns tpm_transmit_cmd() error codes when the TPM command results an
+ * error.
*/
int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max)
{
+ u32 num_bytes = max;
+ u8 *out_ptr = out;
+ int retries = 5;
+ int total = 0;
int rc;
- if (!out || max > TPM_MAX_RNG_DATA)
+ if (!out || !max || max > TPM_MAX_RNG_DATA)
return -EINVAL;
if (!chip)
@@ -508,11 +642,30 @@ int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max)
if (rc)
return rc;
- if (chip->flags & TPM_CHIP_FLAG_TPM2)
- rc = tpm2_get_random(chip, out, max);
- else
- rc = tpm1_get_random(chip, out, max);
+ if (chip->flags & TPM_CHIP_FLAG_TPM2) {
+ rc = tpm2_start_auth_session(chip);
+ if (rc)
+ return rc;
+ }
+
+ do {
+ if (chip->flags & TPM_CHIP_FLAG_TPM2)
+ rc = tpm2_get_random(chip, out_ptr, num_bytes);
+ else
+ rc = tpm1_get_random(chip, out_ptr, num_bytes);
+
+ if (rc < 0)
+ goto err;
+
+ out_ptr += rc;
+ total += rc;
+ num_bytes -= rc;
+ } while (retries-- && total < max);
+
+ tpm_put_ops(chip);
+ return total ? total : -EIO;
+err:
tpm_put_ops(chip);
return rc;
}
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 02c07fef41ba..f698d01401de 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -251,7 +251,6 @@ int tpm1_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash,
int tpm1_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf);
ssize_t tpm1_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
const char *desc, size_t min_cap_length);
-int tpm1_get_random(struct tpm_chip *chip, u8 *out, size_t max);
int tpm1_get_pcr_allocation(struct tpm_chip *chip);
unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal);
int tpm_pm_suspend(struct device *dev);
@@ -291,7 +290,6 @@ int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
struct tpm_digest *digest, u16 *digest_size_ptr);
int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
struct tpm_digest *digests);
-int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max);
ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,
u32 *value, const char *desc);
diff --git a/drivers/char/tpm/tpm1-cmd.c b/drivers/char/tpm/tpm1-cmd.c
index b49a790f1bd5..0604e11c9778 100644
--- a/drivers/char/tpm/tpm1-cmd.c
+++ b/drivers/char/tpm/tpm1-cmd.c
@@ -511,75 +511,6 @@ ssize_t tpm1_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
}
EXPORT_SYMBOL_GPL(tpm1_getcap);
-#define TPM_ORD_GET_RANDOM 70
-struct tpm1_get_random_out {
- __be32 rng_data_len;
- u8 rng_data[TPM_MAX_RNG_DATA];
-} __packed;
-
-/**
- * tpm1_get_random() - get random bytes from the TPM's RNG
- * @chip: a &struct tpm_chip instance
- * @dest: destination buffer for the random bytes
- * @max: the maximum number of bytes to write to @dest
- *
- * Return:
- * * number of bytes read
- * * -errno (positive TPM return codes are masked to -EIO)
- */
-int tpm1_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
-{
- struct tpm1_get_random_out *out;
- u32 num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA);
- struct tpm_buf buf;
- u32 total = 0;
- int retries = 5;
- u32 recd;
- int rc;
-
- rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_RANDOM);
- if (rc)
- return rc;
-
- do {
- tpm_buf_append_u32(&buf, num_bytes);
-
- rc = tpm_transmit_cmd(chip, &buf, sizeof(out->rng_data_len),
- "attempting get random");
- if (rc) {
- if (rc > 0)
- rc = -EIO;
- goto out;
- }
-
- out = (struct tpm1_get_random_out *)&buf.data[TPM_HEADER_SIZE];
-
- recd = be32_to_cpu(out->rng_data_len);
- if (recd > num_bytes) {
- rc = -EFAULT;
- goto out;
- }
-
- if (tpm_buf_length(&buf) < TPM_HEADER_SIZE +
- sizeof(out->rng_data_len) + recd) {
- rc = -EFAULT;
- goto out;
- }
- memcpy(dest, out->rng_data, recd);
-
- dest += recd;
- total += recd;
- num_bytes -= recd;
-
- tpm_buf_reset(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_RANDOM);
- } while (retries-- && total < max);
-
- rc = total ? (int)total : -EIO;
-out:
- tpm_buf_destroy(&buf);
- return rc;
-}
-
#define TPM_ORD_PCRREAD 21
int tpm1_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf)
{
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 1f561ad3bdcf..461e85c3abe5 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -239,110 +239,6 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
return rc;
}
-struct tpm2_get_random_out {
- __be16 size;
- u8 buffer[TPM_MAX_RNG_DATA];
-} __packed;
-
-/**
- * tpm2_get_random() - get random bytes from the TPM RNG
- *
- * @chip: a &tpm_chip instance
- * @dest: destination buffer
- * @max: the max number of random bytes to pull
- *
- * Return:
- * size of the buffer on success,
- * -errno otherwise (positive TPM return codes are masked to -EIO)
- */
-int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
-{
- struct tpm2_get_random_out *out;
- struct tpm_header *head;
- struct tpm_buf buf;
- u32 recd;
- u32 num_bytes = max;
- int err;
- int total = 0;
- int retries = 5;
- u8 *dest_ptr = dest;
- off_t offset;
-
- if (!num_bytes || max > TPM_MAX_RNG_DATA)
- return -EINVAL;
-
- err = tpm2_start_auth_session(chip);
- if (err)
- return err;
-
- err = tpm_buf_init(&buf, 0, 0);
- if (err) {
- tpm2_end_auth_session(chip);
- return err;
- }
-
- do {
- tpm_buf_reset(&buf, TPM2_ST_SESSIONS, TPM2_CC_GET_RANDOM);
- if (tpm2_chip_auth(chip)) {
- tpm_buf_append_hmac_session(chip, &buf,
- TPM2_SA_ENCRYPT |
- TPM2_SA_CONTINUE_SESSION,
- NULL, 0);
- } else {
- offset = buf.handles * 4 + TPM_HEADER_SIZE;
- head = (struct tpm_header *)buf.data;
- if (tpm_buf_length(&buf) == offset)
- head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
- }
- tpm_buf_append_u16(&buf, num_bytes);
- err = tpm_buf_fill_hmac_session(chip, &buf);
- if (err) {
- tpm_buf_destroy(&buf);
- return err;
- }
-
- err = tpm_transmit_cmd(chip, &buf,
- offsetof(struct tpm2_get_random_out,
- buffer),
- "attempting get random");
- err = tpm_buf_check_hmac_response(chip, &buf, err);
- if (err) {
- if (err > 0)
- err = -EIO;
- goto out;
- }
-
- head = (struct tpm_header *)buf.data;
- offset = TPM_HEADER_SIZE;
- /* Skip the parameter size field: */
- if (be16_to_cpu(head->tag) == TPM2_ST_SESSIONS)
- offset += 4;
-
- out = (struct tpm2_get_random_out *)&buf.data[offset];
- recd = min_t(u32, be16_to_cpu(out->size), num_bytes);
- if (tpm_buf_length(&buf) <
- TPM_HEADER_SIZE +
- offsetof(struct tpm2_get_random_out, buffer) +
- recd) {
- err = -EFAULT;
- goto out;
- }
- memcpy(dest_ptr, out->buffer, recd);
-
- dest_ptr += recd;
- total += recd;
- num_bytes -= recd;
- } while (retries-- && total < max);
-
- tpm_buf_destroy(&buf);
-
- return total ? total : -EIO;
-out:
- tpm_buf_destroy(&buf);
- tpm2_end_auth_session(chip);
- return err;
-}
-
/**
* tpm2_flush_context() - execute a TPM2_FlushContext command
* @chip: TPM chip to use
--
2.39.5
^ permalink raw reply related
* [PATCH v6 05/11] tpm2-sessions: Remove AUTH_MAX_NAMES
From: Jarkko Sakkinen @ 2025-12-14 15:38 UTC (permalink / raw)
To: linux-integrity
Cc: Ross Philipson, Jarkko Sakkinen, Peter Huewe, Jason Gunthorpe,
David Howells, Paul Moore, James Morris, Serge E. Hallyn,
open list, open list:KEYS/KEYRINGS, open list:SECURITY SUBSYSTEM
In-Reply-To: <20251214153808.73831-1-jarkko@kernel.org>
In all of the call sites only one session is ever append. Thus, reduce
AUTH_MAX_NAMES, which leads into removing constant completely.
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
drivers/char/tpm/tpm2-sessions.c | 31 +++++++++++--------------------
1 file changed, 11 insertions(+), 20 deletions(-)
diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
index 3bc3c31cf512..37570dc088cf 100644
--- a/drivers/char/tpm/tpm2-sessions.c
+++ b/drivers/char/tpm/tpm2-sessions.c
@@ -72,9 +72,6 @@
#include <crypto/sha2.h>
#include <crypto/utils.h>
-/* maximum number of names the TPM must remember for authorization */
-#define AUTH_MAX_NAMES 3
-
#define AES_KEY_BYTES AES_KEYSIZE_128
#define AES_KEY_BITS (AES_KEY_BYTES*8)
@@ -136,8 +133,8 @@ struct tpm2_auth {
* handle, but they are part of the session by name, which
* we must compute and remember
*/
- u8 name[AUTH_MAX_NAMES][TPM2_MAX_NAME_SIZE];
- u16 name_size_tbl[AUTH_MAX_NAMES];
+ u8 name[TPM2_MAX_NAME_SIZE];
+ u16 name_size;
};
#ifdef CONFIG_TCG_TPM2_HMAC
@@ -261,11 +258,14 @@ EXPORT_SYMBOL_GPL(tpm2_read_public);
int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
u32 handle, u8 *name, u16 name_size)
{
-#ifdef CONFIG_TCG_TPM2_HMAC
struct tpm2_auth *auth;
- int slot;
int ret;
-#endif
+
+ if (tpm_buf_length(buf) != TPM_HEADER_SIZE) {
+ dev_err(&chip->dev, "too many handles\n");
+ ret = -EIO;
+ goto err;
+ }
if (!tpm2_chip_auth(chip)) {
tpm_buf_append_handle(chip, buf, handle);
@@ -273,12 +273,6 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
}
#ifdef CONFIG_TCG_TPM2_HMAC
- slot = (tpm_buf_length(buf) - TPM_HEADER_SIZE) / 4;
- if (slot >= AUTH_MAX_NAMES) {
- dev_err(&chip->dev, "too many handles\n");
- ret = -EIO;
- goto err;
- }
auth = chip->auth;
if (auth->session != tpm_buf_length(buf)) {
dev_err(&chip->dev, "session state malformed");
@@ -287,16 +281,14 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
}
tpm_buf_append_u32(buf, handle);
auth->session += 4;
- memcpy(auth->name[slot], name, name_size);
- auth->name_size_tbl[slot] = name_size;
+ memcpy(auth->name, name, name_size);
+ auth->name_size = name_size;
#endif
return 0;
-#ifdef CONFIG_TCG_TPM2_HMAC
err:
tpm2_end_auth_session(chip);
return ret;
-#endif
}
EXPORT_SYMBOL_GPL(tpm_buf_append_name);
@@ -665,8 +657,7 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf)
/* ordinal is already BE */
sha256_update(&sctx, (u8 *)&head->ordinal, sizeof(head->ordinal));
/* add the handle names */
- for (i = 0; i < handles; i++)
- sha256_update(&sctx, auth->name[i], auth->name_size_tbl[i]);
+ sha256_update(&sctx, auth->name, auth->name_size);
if (offset_s != tpm_buf_length(buf))
sha256_update(&sctx, &buf->data[offset_s],
tpm_buf_length(buf) - offset_s);
--
2.39.5
^ permalink raw reply related
* [PATCH v6 04/11] KEYS: trusted: Re-orchestrate tpm2_read_public() calls
From: Jarkko Sakkinen @ 2025-12-14 15:38 UTC (permalink / raw)
To: linux-integrity
Cc: Ross Philipson, Jarkko Sakkinen, Peter Huewe, Jason Gunthorpe,
David Howells, Paul Moore, James Morris, Serge E. Hallyn,
James Bottomley, Mimi Zohar, open list, open list:KEYS/KEYRINGS,
open list:SECURITY SUBSYSTEM
In-Reply-To: <20251214153808.73831-1-jarkko@kernel.org>
tpm2_load_cmd() and tpm2_unseal_cmd() use the same parent, and calls to
tpm_buf_append_name() cause the exact same TPM2_ReadPublic command to be
sent to the chip, causing unnecessary traffic.
1. Export tpm2_read_public in order to make it callable from
'trusted_tpm2'.
2. Re-orchestrate tpm2_seal_trusted() and tpm2_unseal_trusted() in order to
halve the name resolutions required:
2a. Move tpm2_read_public() calls into trusted_tpm2.
2b. Pass TPM name to tpm_buf_append_name().
2c. Rework tpm_buf_append_name() to use the pre-resolved name.
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
drivers/char/tpm/tpm2-cmd.c | 3 +-
drivers/char/tpm/tpm2-sessions.c | 95 +++++------------
include/linux/tpm.h | 10 +-
security/keys/trusted-keys/trusted_tpm2.c | 124 ++++++++++++++--------
4 files changed, 118 insertions(+), 114 deletions(-)
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 3a77be7ebf4a..1f561ad3bdcf 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -202,7 +202,8 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
}
if (!disable_pcr_integrity) {
- rc = tpm_buf_append_name(chip, &buf, pcr_idx, NULL);
+ rc = tpm_buf_append_name(chip, &buf, pcr_idx, (u8 *)&pcr_idx,
+ sizeof(u32));
if (rc) {
tpm_buf_destroy(&buf);
return rc;
diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
index 525b8622d1c3..3bc3c31cf512 100644
--- a/drivers/char/tpm/tpm2-sessions.c
+++ b/drivers/char/tpm/tpm2-sessions.c
@@ -136,8 +136,8 @@ struct tpm2_auth {
* handle, but they are part of the session by name, which
* we must compute and remember
*/
- u32 name_h[AUTH_MAX_NAMES];
u8 name[AUTH_MAX_NAMES][TPM2_MAX_NAME_SIZE];
+ u16 name_size_tbl[AUTH_MAX_NAMES];
};
#ifdef CONFIG_TCG_TPM2_HMAC
@@ -163,7 +163,17 @@ static int name_size(const u8 *name)
}
}
-static int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name)
+/**
+ * tpm2_read_public: Resolve TPM name for a handle
+ * @chip: TPM chip to use.
+ * @handle: TPM handle.
+ * @name: A buffer for returning the name blob. Must have a
+ * capacity of 'SHA512_DIGET_SIZE + 2' bytes at minimum
+ *
+ * Returns size of TPM handle name of success.
+ * Returns tpm_transmit_cmd error codes when TPM2_ReadPublic fails.
+ */
+int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name)
{
u32 mso = tpm2_handle_mso(handle);
off_t offset = TPM_HEADER_SIZE;
@@ -219,14 +229,16 @@ static int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name)
memcpy(name, &buf.data[offset], rc);
return name_size_alg;
}
+EXPORT_SYMBOL_GPL(tpm2_read_public);
#endif /* CONFIG_TCG_TPM2_HMAC */
/**
- * tpm_buf_append_name() - add a handle area to the buffer
- * @chip: the TPM chip structure
- * @buf: The buffer to be appended
- * @handle: The handle to be appended
- * @name: The name of the handle (may be NULL)
+ * tpm_buf_append_name() - Append a handle and store TPM name
+ * @chip: TPM chip to use.
+ * @buf: TPM buffer containing the TPM command in-transit.
+ * @handle: TPM handle to be appended.
+ * @name: TPM name of the handle
+ * @name_size: Size of the TPM name.
*
* In order to compute session HMACs, we need to know the names of the
* objects pointed to by the handles. For most objects, this is simply
@@ -243,15 +255,14 @@ static int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name)
* will be caused by an incorrect programming model and indicated by a
* kernel message.
*
- * Ends the authorization session on failure.
+ * Returns zero on success.
+ * Returns -EIO when the authorization area state is malformed.
*/
int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
- u32 handle, u8 *name)
+ u32 handle, u8 *name, u16 name_size)
{
#ifdef CONFIG_TCG_TPM2_HMAC
- enum tpm2_mso_type mso = tpm2_handle_mso(handle);
struct tpm2_auth *auth;
- u16 name_size_alg;
int slot;
int ret;
#endif
@@ -276,36 +287,15 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
}
tpm_buf_append_u32(buf, handle);
auth->session += 4;
-
- if (mso == TPM2_MSO_PERSISTENT ||
- mso == TPM2_MSO_VOLATILE ||
- mso == TPM2_MSO_NVRAM) {
- if (!name) {
- ret = tpm2_read_public(chip, handle, auth->name[slot]);
- if (ret < 0)
- goto err;
-
- name_size_alg = ret;
- }
- } else {
- if (name) {
- dev_err(&chip->dev, "handle 0x%08x does not use a name\n",
- handle);
- ret = -EIO;
- goto err;
- }
- }
-
- auth->name_h[slot] = handle;
- if (name)
- memcpy(auth->name[slot], name, name_size_alg);
+ memcpy(auth->name[slot], name, name_size);
+ auth->name_size_tbl[slot] = name_size;
#endif
return 0;
#ifdef CONFIG_TCG_TPM2_HMAC
err:
tpm2_end_auth_session(chip);
- return tpm_ret_to_err(ret);
+ return ret;
#endif
}
EXPORT_SYMBOL_GPL(tpm_buf_append_name);
@@ -613,22 +603,8 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf)
attrs = chip->cc_attrs_tbl[i];
handles = (attrs >> TPM2_CC_ATTR_CHANDLES) & GENMASK(2, 0);
+ offset_s += handles * sizeof(u32);
- /*
- * just check the names, it's easy to make mistakes. This
- * would happen if someone added a handle via
- * tpm_buf_append_u32() instead of tpm_buf_append_name()
- */
- for (i = 0; i < handles; i++) {
- u32 handle = tpm_buf_read_u32(buf, &offset_s);
-
- if (auth->name_h[i] != handle) {
- dev_err(&chip->dev, "invalid handle 0x%08x\n", handle);
- ret = -EIO;
- goto err;
- }
- }
- /* point offset_s to the start of the sessions */
val = tpm_buf_read_u32(buf, &offset_s);
/* point offset_p to the start of the parameters */
offset_p = offset_s + val;
@@ -689,23 +665,8 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf)
/* ordinal is already BE */
sha256_update(&sctx, (u8 *)&head->ordinal, sizeof(head->ordinal));
/* add the handle names */
- for (i = 0; i < handles; i++) {
- enum tpm2_mso_type mso = tpm2_handle_mso(auth->name_h[i]);
-
- if (mso == TPM2_MSO_PERSISTENT ||
- mso == TPM2_MSO_VOLATILE ||
- mso == TPM2_MSO_NVRAM) {
- ret = name_size(auth->name[i]);
- if (ret < 0)
- goto err;
-
- sha256_update(&sctx, auth->name[i], ret);
- } else {
- __be32 h = cpu_to_be32(auth->name_h[i]);
-
- sha256_update(&sctx, (u8 *)&h, 4);
- }
- }
+ for (i = 0; i < handles; i++)
+ sha256_update(&sctx, auth->name[i], auth->name_size_tbl[i]);
if (offset_s != tpm_buf_length(buf))
sha256_update(&sctx, &buf->data[offset_s],
tpm_buf_length(buf) - offset_s);
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index e10f2096eae7..72610f1aa402 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -543,7 +543,7 @@ static inline struct tpm2_auth *tpm2_chip_auth(struct tpm_chip *chip)
}
int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
- u32 handle, u8 *name);
+ u32 handle, u8 *name, u16 name_size);
void tpm_buf_append_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf,
u8 attributes, u8 *passphrase,
int passphraselen);
@@ -557,6 +557,7 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf);
int tpm_buf_check_hmac_response(struct tpm_chip *chip, struct tpm_buf *buf,
int rc);
void tpm2_end_auth_session(struct tpm_chip *chip);
+int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name);
#else
#include <linux/unaligned.h>
@@ -580,6 +581,13 @@ static inline int tpm_buf_check_hmac_response(struct tpm_chip *chip,
{
return rc;
}
+
+static inline int tpm2_read_public(struct tpm_chip *chip, u32 handle,
+ void *name)
+{
+ memcpy(name, &handle, sizeof(u32));
+ return sizeof(u32);
+}
#endif /* CONFIG_TCG_TPM2_HMAC */
#endif
diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
index 3666e3e48eab..3de84b30b655 100644
--- a/security/keys/trusted-keys/trusted_tpm2.c
+++ b/security/keys/trusted-keys/trusted_tpm2.c
@@ -203,8 +203,10 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options)
{
+ u8 parent_name[TPM2_MAX_NAME_SIZE];
off_t offset = TPM_HEADER_SIZE;
struct tpm_buf buf, sized;
+ u16 parent_name_size;
int blob_len = 0;
int hash;
u32 flags;
@@ -221,6 +223,12 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
if (rc)
return rc;
+ rc = tpm2_read_public(chip, options->keyhandle, parent_name);
+ if (rc < 0)
+ goto out_put;
+
+ parent_name_size = rc;
+
rc = tpm2_start_auth_session(chip);
if (rc)
goto out_put;
@@ -238,7 +246,8 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
goto out_put;
}
- rc = tpm_buf_append_name(chip, &buf, options->keyhandle, NULL);
+ rc = tpm_buf_append_name(chip, &buf, options->keyhandle, parent_name,
+ parent_name_size);
if (rc)
goto out;
@@ -325,21 +334,25 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
}
/**
- * tpm2_load_cmd() - execute a TPM2_Load command
- *
- * @chip: TPM chip to use
- * @payload: the key data in clear and encrypted form
- * @options: authentication values and other options
- * @blob_handle: returned blob handle
+ * tpm2_load_cmd() - Execute TPM2_Load
+ * @chip: TPM chip to use.
+ * @payload: Key data in clear text.
+ * @options: Trusted key options.
+ * @parent_name: A cryptographic name, i.e. a TPMT_HA blob, of the
+ * parent key.
+ * @blob: The decoded payload for the key.
+ * @blob_handle: On success, will contain handle to the loaded keyedhash
+ * blob.
*
- * Return: 0 on success.
- * -E2BIG on wrong payload size.
- * -EPERM on tpm error status.
- * < 0 error from tpm_send.
+ * Return -E2BIG when the blob size is too small for all the data.
+ * Returns tpm_transmit_cmd() error codes when either TPM2_Load fails.
*/
static int tpm2_load_cmd(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options,
+ u8 *parent_name,
+ u16 parent_name_size,
+ const u8 *blob,
u32 *blob_handle)
{
u8 *blob_ref __free(kfree) = NULL;
@@ -347,27 +360,13 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
unsigned int private_len;
unsigned int public_len;
unsigned int blob_len;
- u8 *blob, *pub;
+ const u8 *pub;
int rc;
u32 attrs;
- rc = tpm2_key_decode(payload, options, &blob);
- if (rc) {
- /* old form */
- blob = payload->blob;
- payload->old_format = 1;
- } else {
- /* Bind for cleanup: */
- blob_ref = blob;
- }
-
- /* new format carries keyhandle but old format doesn't */
- if (!options->keyhandle)
- return -EINVAL;
-
/* must be big enough for at least the two be16 size counts */
if (payload->blob_len < 4)
- return -EINVAL;
+ return -E2BIG;
private_len = get_unaligned_be16(blob);
@@ -403,7 +402,8 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
return rc;
}
- rc = tpm_buf_append_name(chip, &buf, options->keyhandle, NULL);
+ rc = tpm_buf_append_name(chip, &buf, options->keyhandle, parent_name,
+ parent_name_size);
if (rc)
goto out;
@@ -435,20 +435,23 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
}
/**
- * tpm2_unseal_cmd() - execute a TPM2_Unload command
+ * tpm2_unseal_cmd() - Execute TPM2_Unload
*
- * @chip: TPM chip to use
- * @payload: the key data in clear and encrypted form
- * @options: authentication values and other options
- * @blob_handle: blob handle
+ * @chip: TPM chip to use
+ * @payload: Key data in clear text.
+ * @options: Trusted key options.
+ * @parent_name: A cryptographic name, i.e. a TPMT_HA blob, of the
+ * parent key.
+ * @blob_handle: Handle to the loaded keyedhash blob.
*
- * Return: 0 on success
- * -EPERM on tpm error status
- * < 0 error from tpm_send
+ * Return -E2BIG when the blob size is too small for all the data.
+ * Returns tpm_transmit_cmd() error codes when either TPM2_Load fails.
*/
static int tpm2_unseal_cmd(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options,
+ u8 *parent_name,
+ u16 parent_name_size,
u32 blob_handle)
{
struct tpm_buf buf;
@@ -466,7 +469,8 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
return rc;
}
- rc = tpm_buf_append_name(chip, &buf, options->keyhandle, NULL);
+ rc = tpm_buf_append_name(chip, &buf, options->keyhandle, parent_name,
+ parent_name_size);
if (rc)
goto out;
@@ -539,30 +543,60 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
}
/**
- * tpm2_unseal_trusted() - unseal the payload of a trusted key
+ * tpm2_unseal_trusted() - Unseal a trusted key
+ * @chip: TPM chip to use.
+ * @payload: Key data in clear text.
+ * @options: Trusted key options.
*
- * @chip: TPM chip to use
- * @payload: the key data in clear and encrypted form
- * @options: authentication values and other options
- *
- * Return: Same as with tpm_send.
+ * Return -E2BIG when the blob size is too small for all the data.
+ * Return -EINVAL when parent's key handle has not been set.
+ * Returns tpm_transmit_cmd() error codes when either TPM2_Load or TPM2_Unseal
+ * fails.
*/
int tpm2_unseal_trusted(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options)
{
+ u8 *blob_ref __free(kfree) = NULL;
+ u8 parent_name[TPM2_MAX_NAME_SIZE];
+ u16 parent_name_size;
u32 blob_handle;
+ u8 *blob;
int rc;
+ /*
+ * Try to decode the provided blob as an ASN.1 blob. Assume that the
+ * blob is in the legacy format if decoding does not end successfully.
+ */
+ rc = tpm2_key_decode(payload, options, &blob);
+ if (rc) {
+ blob = payload->blob;
+ payload->old_format = 1;
+ } else {
+ blob_ref = blob;
+ }
+
+ if (!options->keyhandle)
+ return -EINVAL;
+
rc = tpm_try_get_ops(chip);
if (rc)
return rc;
- rc = tpm2_load_cmd(chip, payload, options, &blob_handle);
+ rc = tpm2_read_public(chip, options->keyhandle, parent_name);
+ if (rc < 0)
+ goto out;
+
+ parent_name_size = rc;
+
+ rc = tpm2_load_cmd(chip, payload, options, parent_name,
+ parent_name_size, blob, &blob_handle);
if (rc)
goto out;
- rc = tpm2_unseal_cmd(chip, payload, options, blob_handle);
+ rc = tpm2_unseal_cmd(chip, payload, options, parent_name,
+ parent_name_size, blob_handle);
+
tpm2_flush_context(chip, blob_handle);
out:
--
2.39.5
^ permalink raw reply related
* [PATCH v6 03/11] KEYS: trusted: Remove dead branch from tpm2_unseal_cmd
From: Jarkko Sakkinen @ 2025-12-14 15:38 UTC (permalink / raw)
To: linux-integrity
Cc: Ross Philipson, Jarkko Sakkinen, David Howells, Paul Moore,
James Morris, Serge E. Hallyn, James Bottomley, Mimi Zohar,
open list:KEYS/KEYRINGS, open list:SECURITY SUBSYSTEM, open list
In-Reply-To: <20251214153808.73831-1-jarkko@kernel.org>
TPM2_Unseal requires TPM2_ST_SESSIONS, and tpm2_unseal_cmd() always does
set up either password or HMAC session.
Remove the branch in tpm2_unseal_cmd() conditionally setting
TPM2_ST_NO_SESSIONS. It is faulty but luckily it is never exercised at
run-time, and thus does not cause regressions.
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
security/keys/trusted-keys/trusted_tpm2.c | 10 +---------
1 file changed, 1 insertion(+), 9 deletions(-)
diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
index d3a5c5f2b926..3666e3e48eab 100644
--- a/security/keys/trusted-keys/trusted_tpm2.c
+++ b/security/keys/trusted-keys/trusted_tpm2.c
@@ -451,10 +451,8 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
struct trusted_key_options *options,
u32 blob_handle)
{
- struct tpm_header *head;
struct tpm_buf buf;
u16 data_len;
- int offset;
u8 *data;
int rc;
@@ -495,14 +493,8 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
tpm_buf_append_u16(&buf, options->blobauth_len);
tpm_buf_append(&buf, options->blobauth, options->blobauth_len);
- if (tpm2_chip_auth(chip)) {
+ if (tpm2_chip_auth(chip))
tpm_buf_append_hmac_session(chip, &buf, TPM2_SA_ENCRYPT, NULL, 0);
- } else {
- offset = buf.handles * 4 + TPM_HEADER_SIZE;
- head = (struct tpm_header *)buf.data;
- if (tpm_buf_length(&buf) == offset)
- head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
- }
}
rc = tpm_buf_fill_hmac_session(chip, &buf);
--
2.39.5
^ permalink raw reply related
* [PATCH v6 02/11] KEYS: trusted: Open code tpm2_buf_append()
From: Jarkko Sakkinen @ 2025-12-14 15:37 UTC (permalink / raw)
To: linux-integrity
Cc: Ross Philipson, Jarkko Sakkinen, Jonathan McDowell, David Howells,
Jarkko Sakkinen, Paul Moore, James Morris, Serge E. Hallyn,
James Bottomley, Mimi Zohar, open list:KEYS/KEYRINGS,
open list:SECURITY SUBSYSTEM, open list
In-Reply-To: <20251214153808.73831-1-jarkko@kernel.org>
From: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
tpm2_buf_append_auth() has a single call site and most of its parameters
are redundant. Open code it to the call site so that less cross-referencing
is required while browsing the source code.
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
Reviewed-by: Jonathan McDowell <noodles@earth.li>
---
v6:
- Trimmed the patch by removing comment update as it is out of scope.
---
security/keys/trusted-keys/trusted_tpm2.c | 40 ++++-------------------
1 file changed, 7 insertions(+), 33 deletions(-)
diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
index a7ea4a1c3bed..d3a5c5f2b926 100644
--- a/security/keys/trusted-keys/trusted_tpm2.c
+++ b/security/keys/trusted-keys/trusted_tpm2.c
@@ -190,36 +190,6 @@ int tpm2_key_priv(void *context, size_t hdrlen,
return 0;
}
-/**
- * tpm2_buf_append_auth() - append TPMS_AUTH_COMMAND to the buffer.
- *
- * @buf: an allocated tpm_buf instance
- * @session_handle: session handle
- * @nonce: the session nonce, may be NULL if not used
- * @nonce_len: the session nonce length, may be 0 if not used
- * @attributes: the session attributes
- * @hmac: the session HMAC or password, may be NULL if not used
- * @hmac_len: the session HMAC or password length, maybe 0 if not used
- */
-static void tpm2_buf_append_auth(struct tpm_buf *buf, u32 session_handle,
- const u8 *nonce, u16 nonce_len,
- u8 attributes,
- const u8 *hmac, u16 hmac_len)
-{
- tpm_buf_append_u32(buf, 9 + nonce_len + hmac_len);
- tpm_buf_append_u32(buf, session_handle);
- tpm_buf_append_u16(buf, nonce_len);
-
- if (nonce && nonce_len)
- tpm_buf_append(buf, nonce, nonce_len);
-
- tpm_buf_append_u8(buf, attributes);
- tpm_buf_append_u16(buf, hmac_len);
-
- if (hmac && hmac_len)
- tpm_buf_append(buf, hmac, hmac_len);
-}
-
/**
* tpm2_seal_trusted() - seal the payload of a trusted key
*
@@ -518,9 +488,13 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
* could repeat our actions with the exfiltrated
* password.
*/
- tpm2_buf_append_auth(&buf, options->policyhandle,
- NULL /* nonce */, 0, 0,
- options->blobauth, options->blobauth_len);
+ tpm_buf_append_u32(&buf, 9 + options->blobauth_len);
+ tpm_buf_append_u32(&buf, options->policyhandle);
+ tpm_buf_append_u16(&buf, 0);
+ tpm_buf_append_u8(&buf, 0);
+ tpm_buf_append_u16(&buf, options->blobauth_len);
+ tpm_buf_append(&buf, options->blobauth, options->blobauth_len);
+
if (tpm2_chip_auth(chip)) {
tpm_buf_append_hmac_session(chip, &buf, TPM2_SA_ENCRYPT, NULL, 0);
} else {
--
2.39.5
^ permalink raw reply related
* [PATCH v6 01/11] tpm2-sessions: Define TPM2_NAME_MAX_SIZE
From: Jarkko Sakkinen @ 2025-12-14 15:37 UTC (permalink / raw)
To: linux-integrity
Cc: Ross Philipson, Jarkko Sakkinen, Peter Huewe, Jason Gunthorpe,
David Howells, Paul Moore, James Morris, Serge E. Hallyn,
open list, open list:KEYS/KEYRINGS, open list:SECURITY SUBSYSTEM
In-Reply-To: <20251214153808.73831-1-jarkko@kernel.org>
Define TPM2_NAME_MAX_SIZE, which describes the maximum size for hashes
encoded as TPMT_HA, which the prime identifier used for persistent and
transient keys in TPM2 protocol.
Set its value to 'SHA512_DIGEST_SIZE + 2', as SHA512 has the largest
digest size of the algorithms in TCG algorithm repository.
In additionl, rename TPM2_NAME_SIZE as TPM2_NULL_NAME_SIZE in order to
avoid any possible confusion.
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
v6:
- Rewrote the commit message.
v2:
- Rename TPM2_NAME_SIZE as TPM2_NULL_NAME_SIZE.
---
drivers/char/tpm/tpm-sysfs.c | 2 +-
drivers/char/tpm/tpm2-sessions.c | 2 +-
include/linux/tpm.h | 37 +++++++++++++++++++++-----------
3 files changed, 27 insertions(+), 14 deletions(-)
diff --git a/drivers/char/tpm/tpm-sysfs.c b/drivers/char/tpm/tpm-sysfs.c
index 94231f052ea7..4a6a27ee295d 100644
--- a/drivers/char/tpm/tpm-sysfs.c
+++ b/drivers/char/tpm/tpm-sysfs.c
@@ -314,7 +314,7 @@ static ssize_t null_name_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct tpm_chip *chip = to_tpm_chip(dev);
- int size = TPM2_NAME_SIZE;
+ int size = TPM2_NULL_NAME_SIZE;
bin2hex(buf, chip->null_key_name, size);
size *= 2;
diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
index 4149379665c4..525b8622d1c3 100644
--- a/drivers/char/tpm/tpm2-sessions.c
+++ b/drivers/char/tpm/tpm2-sessions.c
@@ -137,7 +137,7 @@ struct tpm2_auth {
* we must compute and remember
*/
u32 name_h[AUTH_MAX_NAMES];
- u8 name[AUTH_MAX_NAMES][2 + SHA512_DIGEST_SIZE];
+ u8 name[AUTH_MAX_NAMES][TPM2_MAX_NAME_SIZE];
};
#ifdef CONFIG_TCG_TPM2_HMAC
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 202da079d500..e10f2096eae7 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -27,9 +27,33 @@
#define TPM_DIGEST_SIZE 20 /* Max TPM v1.2 PCR size */
+/*
+ * SHA-512 is, as of today, the largest digest in the TCG algorithm repository.
+ */
#define TPM2_MAX_DIGEST_SIZE SHA512_DIGEST_SIZE
+
+/*
+ * A TPM name digest i.e., TPMT_HA, is a concatenation of TPM_ALG_ID of the
+ * name algorithm and hash of TPMT_PUBLIC.
+ */
+#define TPM2_MAX_NAME_SIZE (TPM2_MAX_DIGEST_SIZE + 2)
+
+/*
+ * The maximum number of PCR banks.
+ */
#define TPM2_MAX_PCR_BANKS 8
+/*
+ * fixed define for the size of a name. This is actually HASHALG size
+ * plus 2, so 32 for SHA256
+ */
+#define TPM2_NULL_NAME_SIZE 34
+
+/*
+ * The maximum size for an object context
+ */
+#define TPM2_MAX_CONTEXT_SIZE 4096
+
struct tpm_chip;
struct trusted_key_payload;
struct trusted_key_options;
@@ -139,17 +163,6 @@ struct tpm_chip_seqops {
/* fixed define for the curve we use which is NIST_P256 */
#define EC_PT_SZ 32
-/*
- * fixed define for the size of a name. This is actually HASHALG size
- * plus 2, so 32 for SHA256
- */
-#define TPM2_NAME_SIZE 34
-
-/*
- * The maximum size for an object context
- */
-#define TPM2_MAX_CONTEXT_SIZE 4096
-
struct tpm_chip {
struct device dev;
struct device devs;
@@ -211,7 +224,7 @@ struct tpm_chip {
/* saved context for NULL seed */
u8 null_key_context[TPM2_MAX_CONTEXT_SIZE];
/* name of NULL seed */
- u8 null_key_name[TPM2_NAME_SIZE];
+ u8 null_key_name[TPM2_NULL_NAME_SIZE];
u8 null_ec_key_x[EC_PT_SZ];
u8 null_ec_key_y[EC_PT_SZ];
struct tpm2_auth *auth;
--
2.39.5
^ permalink raw reply related
* [PATCH v6 00/11] Streamline TPM2 HMAC sessions
From: Jarkko Sakkinen @ 2025-12-14 15:37 UTC (permalink / raw)
To: linux-integrity
Cc: Ross Philipson, Jarkko Sakkinen, David Howells, Paul Moore,
James Morris, Serge E. Hallyn, open list:KEYS/KEYRINGS,
open list:SECURITY SUBSYSTEM, open list
Since we cannot at this point cache names of the keys given limitations
of the ASN.1 file format, I'll start a fresh patch set. Let's fixup what
we can right now.
This patch set addresses two major issues in the feature:
1. Dynamic resolution without gain. All kernel sites have at most single
handle to authorize. Even if this changes some day this is how it is
as of today and we definitely do not want to dictate the future but
instead downscale code to the metrics that we have as of today.
2. Eliminate at least one unnnecessary tpm2_read_public() call.
Change Log
==========
v6:
- OK, so I decided to send one more update with managed allocations
moved to the tail so that it does not block reviewing more trivial
patches.
- Trimmed some of the patches and improved commit messages.
v5:
- I decided to add the managed allocation patch to this and take it from
the master branch for the time being, as it needs more eyes despite
having already one reviewed-by tag (especially tested-by tags).
Jarkko Sakkinen (11):
tpm2-sessions: Define TPM2_NAME_MAX_SIZE
KEYS: trusted: Open code tpm2_buf_append()
KEYS: trusted: Remove dead branch from tpm2_unseal_cmd
KEYS: trusted: Re-orchestrate tpm2_read_public() calls
tpm2-sessions: Remove AUTH_MAX_NAMES
tpm: Orchestrate TPM commands in tpm_get_random()
tpm: Send only one at most TPM2_GetRandom command
tpm: In tpm_get_random() replace 'retries' with a zero check
tpm-buf: Merge TPM_BUF_BOUNDARY_ERROR and TPM_BUF_OVERFLOW
tpm-buf: Implement managed allocations
tpm-buf: Remove tpm_buf_append_handle
drivers/char/tpm/tpm-buf.c | 154 ++++-----
drivers/char/tpm/tpm-chip.c | 2 +-
drivers/char/tpm/tpm-interface.c | 177 ++++++++++-
drivers/char/tpm/tpm-sysfs.c | 23 +-
drivers/char/tpm/tpm.h | 3 -
drivers/char/tpm/tpm1-cmd.c | 198 ++++--------
drivers/char/tpm/tpm2-cmd.c | 371 +++++++---------------
drivers/char/tpm/tpm2-sessions.c | 272 ++++++----------
drivers/char/tpm/tpm2-space.c | 44 ++-
drivers/char/tpm/tpm_vtpm_proxy.c | 30 +-
include/linux/tpm.h | 79 +++--
security/keys/trusted-keys/trusted_tpm1.c | 44 +--
security/keys/trusted-keys/trusted_tpm2.c | 329 ++++++++++---------
13 files changed, 799 insertions(+), 927 deletions(-)
--
2.39.5
^ permalink raw reply
* Re: [PATCH] host/roots: Sandbox xdg-desktop-portal-spectrum-host
From: Demi Marie Obenour @ 2025-12-14 4:49 UTC (permalink / raw)
To: Alyssa Ross; +Cc: Spectrum OS Development, linux-security-module, landlock
In-Reply-To: <87bjk16dvv.fsf@alyssa.is>
[-- Attachment #1.1.1: Type: text/plain, Size: 3864 bytes --]
On 12/13/25 20:39, Alyssa Ross wrote:
> Demi Marie Obenour <demiobenour@gmail.com> writes:
>
>> On 12/13/25 16:42, Alyssa Ross wrote:
>>> Demi Marie Obenour <demiobenour@gmail.com> writes:
>>>
>>>> On 12/13/25 14:12, Alyssa Ross wrote:
>>>>> Demi Marie Obenour <demiobenour@gmail.com> writes:
>>>>>
>>>>>> It is quite possible that these Landlock rules are unnecessarily
>>>>>> permissive, but all of the paths to which read and execute access is
>>>>>> granted are part of the root filesystem and therefore assumed to be
>>>>>> public knowledge. Removing access from any of them would only increase
>>>>>> the risk of accidental breakage in the future, and would not provide any
>>>>>> security improvements. seccomp *could* provide some improvements, but
>>>>>> the effort needed is too high for now.
>>>>>>
>>>>>> Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com>
>>>>>> ---
>>>>>> .../template/data/service/xdg-desktop-portal-spectrum-host/run | 8 ++++++++
>>>>>> 1 file changed, 8 insertions(+)
>>>>>
>>>>> Are you sure this is working as intended? There's no rule allowing
>>>>> access to Cloud Hypervisor's VSOCK socket, and yet it still seems to be
>>>>> able to access that. Don't you need to set a rule that *restricts*
>>>>> filesystem access and then add holes? Did you ever see this deny
>>>>> anything?
>>>>
>>>> 'man 1 setpriv' states that '--landlock-access fs' blocks all
>>>> filesystem access unless a subsequent --landlock-rule permits it.
>>>> I tried running with no --landlock-rule flags and the execve of
>>>> xdg-desktop-portal-spectrum-host failed as expected.
>>>>
>>>> The socket is passed over stdin, and I'm pretty sure Landlock
>>>> doesn't restrict using an already-open file descriptor.
>>>> xdg-desktop-portal-spectrum-host does need to find the path to the
>>>> socket, but I don't think it ever accesses that path.
>>>
>>> I've been looking into this a bit myself, and from what I can tell
>>> Landlock just doesn't restrict connecting to sockets at all, even if
>>> they're inside directories that would otherwise be inaccessible. It's
>>> able to connect to both Cloud Hypervisor's VSOCK socket and the D-Bus
>>> socket even with a maximally restrictive landlock rule. So you were
>>> right after all, sorry!
>>
>> That's not good at all! It's a trivial sandbox escape in so many cases.
>> For instance, with access to D-Bus I can just call `systemd-run`.
>>
>> I'm CCing the Landlock and LSM mailing lists because if you are
>> correct, then this is a bad security hole.
>
> I don't find it that surprising given the way landlock works. "connect"
> (to a non-abstract AF_UNIX socket) is not an operation there's a
> landlock action for, and it's not like the other actions care about
> access to parent directories and the like — I was able to execute a
> program via a symlink after only giving access to the symlink's target,
> without any access to the directory containing the symlink or the
> symlink itself, for example. Landlock, as I understand it, is intended
> to block a specified set of operations (on particular file hierarchies),
> rather than to completely prevent access to those hierarchies like
> permissions or mount namespaces could, so the lack of a way to block
> connecting to a socket is more of a missing feature than a security
> hole.
'man 7 unix' states:
On Linux, connecting to a stream socket object requires write
permission on that socket; sending a datagram to a datagram socket
likewise requires write permission on that socket.
Landlock is definitely being inconsistent with DAC here. Also, this
allows real-world sandbox breakouts. On systemd systems, the simplest
way to escape is to use systemd-run to execute arbitrary commands.
--
Sincerely,
Demi Marie Obenour (she/her/hers)
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