From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org,
"Eric W. Biederman" <ebiederm@xmission.com>,
Alexey Gladkov <legion@kernel.org>,
Sasha Levin <sashal@kernel.org>
Subject: [PATCH 5.10 08/29] Revert "Add a reference to ucounts for each cred"
Date: Mon, 6 Sep 2021 14:55:23 +0200 [thread overview]
Message-ID: <20210906125450.059929060@linuxfoundation.org> (raw)
In-Reply-To: <20210906125449.756437409@linuxfoundation.org>
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit b2c4d9a33cc2dec7466f97eba2c4dd571ad798a5 which is
commit 905ae01c4ae2ae3df05bb141801b1db4b7d83c61 upstream.
This commit should not have been applied to the 5.10.y stable tree, so
revert it.
Reported-by: "Eric W. Biederman" <ebiederm@xmission.com>
Link: https://lore.kernel.org/r/87v93k4bl6.fsf@disp2133
Cc: Alexey Gladkov <legion@kernel.org>
Cc: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/exec.c | 4 ----
include/linux/cred.h | 2 --
include/linux/user_namespace.h | 4 ----
kernel/cred.c | 40 ----------------------------------------
kernel/fork.c | 6 ------
kernel/sys.c | 12 ------------
kernel/ucount.c | 40 +++-------------------------------------
kernel/user_namespace.c | 3 ---
8 files changed, 3 insertions(+), 108 deletions(-)
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1347,10 +1347,6 @@ int begin_new_exec(struct linux_binprm *
WRITE_ONCE(me->self_exec_id, me->self_exec_id + 1);
flush_signal_handlers(me, 0);
- retval = set_cred_ucounts(bprm->cred);
- if (retval < 0)
- goto out_unlock;
-
/*
* install the new credentials for this executable
*/
--- a/include/linux/cred.h
+++ b/include/linux/cred.h
@@ -144,7 +144,6 @@ struct cred {
#endif
struct user_struct *user; /* real user ID subscription */
struct user_namespace *user_ns; /* user_ns the caps and keyrings are relative to. */
- struct ucounts *ucounts;
struct group_info *group_info; /* supplementary groups for euid/fsgid */
/* RCU deletion */
union {
@@ -171,7 +170,6 @@ extern int set_security_override_from_ct
extern int set_create_files_as(struct cred *, struct inode *);
extern int cred_fscmp(const struct cred *, const struct cred *);
extern void __init cred_init(void);
-extern int set_cred_ucounts(struct cred *);
/*
* check for validity of credentials
--- a/include/linux/user_namespace.h
+++ b/include/linux/user_namespace.h
@@ -101,15 +101,11 @@ struct ucounts {
};
extern struct user_namespace init_user_ns;
-extern struct ucounts init_ucounts;
bool setup_userns_sysctls(struct user_namespace *ns);
void retire_userns_sysctls(struct user_namespace *ns);
struct ucounts *inc_ucount(struct user_namespace *ns, kuid_t uid, enum ucount_type type);
void dec_ucount(struct ucounts *ucounts, enum ucount_type type);
-struct ucounts *alloc_ucounts(struct user_namespace *ns, kuid_t uid);
-struct ucounts *get_ucounts(struct ucounts *ucounts);
-void put_ucounts(struct ucounts *ucounts);
#ifdef CONFIG_USER_NS
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -60,7 +60,6 @@ struct cred init_cred = {
.user = INIT_USER,
.user_ns = &init_user_ns,
.group_info = &init_groups,
- .ucounts = &init_ucounts,
};
static inline void set_cred_subscribers(struct cred *cred, int n)
@@ -120,8 +119,6 @@ static void put_cred_rcu(struct rcu_head
if (cred->group_info)
put_group_info(cred->group_info);
free_uid(cred->user);
- if (cred->ucounts)
- put_ucounts(cred->ucounts);
put_user_ns(cred->user_ns);
kmem_cache_free(cred_jar, cred);
}
@@ -225,7 +222,6 @@ struct cred *cred_alloc_blank(void)
#ifdef CONFIG_DEBUG_CREDENTIALS
new->magic = CRED_MAGIC;
#endif
- new->ucounts = get_ucounts(&init_ucounts);
if (security_cred_alloc_blank(new, GFP_KERNEL_ACCOUNT) < 0)
goto error;
@@ -288,11 +284,6 @@ struct cred *prepare_creds(void)
if (security_prepare_creds(new, old, GFP_KERNEL_ACCOUNT) < 0)
goto error;
-
- new->ucounts = get_ucounts(new->ucounts);
- if (!new->ucounts)
- goto error;
-
validate_creds(new);
return new;
@@ -372,8 +363,6 @@ int copy_creds(struct task_struct *p, un
ret = create_user_ns(new);
if (ret < 0)
goto error_put;
- if (set_cred_ucounts(new) < 0)
- goto error_put;
}
#ifdef CONFIG_KEYS
@@ -664,31 +653,6 @@ int cred_fscmp(const struct cred *a, con
}
EXPORT_SYMBOL(cred_fscmp);
-int set_cred_ucounts(struct cred *new)
-{
- struct task_struct *task = current;
- const struct cred *old = task->real_cred;
- struct ucounts *old_ucounts = new->ucounts;
-
- if (new->user == old->user && new->user_ns == old->user_ns)
- return 0;
-
- /*
- * This optimization is needed because alloc_ucounts() uses locks
- * for table lookups.
- */
- if (old_ucounts && old_ucounts->ns == new->user_ns && uid_eq(old_ucounts->uid, new->euid))
- return 0;
-
- if (!(new->ucounts = alloc_ucounts(new->user_ns, new->euid)))
- return -EAGAIN;
-
- if (old_ucounts)
- put_ucounts(old_ucounts);
-
- return 0;
-}
-
/*
* initialise the credentials stuff
*/
@@ -755,10 +719,6 @@ struct cred *prepare_kernel_cred(struct
if (security_prepare_creds(new, old, GFP_KERNEL_ACCOUNT) < 0)
goto error;
- new->ucounts = get_ucounts(new->ucounts);
- if (!new->ucounts)
- goto error;
-
put_cred(old);
validate_creds(new);
return new;
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -2960,12 +2960,6 @@ int ksys_unshare(unsigned long unshare_f
if (err)
goto bad_unshare_cleanup_cred;
- if (new_cred) {
- err = set_cred_ucounts(new_cred);
- if (err)
- goto bad_unshare_cleanup_cred;
- }
-
if (new_fs || new_fd || do_sysvsem || new_cred || new_nsproxy) {
if (do_sysvsem) {
/*
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -552,10 +552,6 @@ long __sys_setreuid(uid_t ruid, uid_t eu
if (retval < 0)
goto error;
- retval = set_cred_ucounts(new);
- if (retval < 0)
- goto error;
-
return commit_creds(new);
error:
@@ -614,10 +610,6 @@ long __sys_setuid(uid_t uid)
if (retval < 0)
goto error;
- retval = set_cred_ucounts(new);
- if (retval < 0)
- goto error;
-
return commit_creds(new);
error:
@@ -693,10 +685,6 @@ long __sys_setresuid(uid_t ruid, uid_t e
if (retval < 0)
goto error;
- retval = set_cred_ucounts(new);
- if (retval < 0)
- goto error;
-
return commit_creds(new);
error:
--- a/kernel/ucount.c
+++ b/kernel/ucount.c
@@ -8,12 +8,6 @@
#include <linux/kmemleak.h>
#include <linux/user_namespace.h>
-struct ucounts init_ucounts = {
- .ns = &init_user_ns,
- .uid = GLOBAL_ROOT_UID,
- .count = 1,
-};
-
#define UCOUNTS_HASHTABLE_BITS 10
static struct hlist_head ucounts_hashtable[(1 << UCOUNTS_HASHTABLE_BITS)];
static DEFINE_SPINLOCK(ucounts_lock);
@@ -131,15 +125,7 @@ static struct ucounts *find_ucounts(stru
return NULL;
}
-static void hlist_add_ucounts(struct ucounts *ucounts)
-{
- struct hlist_head *hashent = ucounts_hashentry(ucounts->ns, ucounts->uid);
- spin_lock_irq(&ucounts_lock);
- hlist_add_head(&ucounts->node, hashent);
- spin_unlock_irq(&ucounts_lock);
-}
-
-struct ucounts *alloc_ucounts(struct user_namespace *ns, kuid_t uid)
+static struct ucounts *get_ucounts(struct user_namespace *ns, kuid_t uid)
{
struct hlist_head *hashent = ucounts_hashentry(ns, uid);
struct ucounts *ucounts, *new;
@@ -174,26 +160,7 @@ struct ucounts *alloc_ucounts(struct use
return ucounts;
}
-struct ucounts *get_ucounts(struct ucounts *ucounts)
-{
- unsigned long flags;
-
- if (!ucounts)
- return NULL;
-
- spin_lock_irqsave(&ucounts_lock, flags);
- if (ucounts->count == INT_MAX) {
- WARN_ONCE(1, "ucounts: counter has reached its maximum value");
- ucounts = NULL;
- } else {
- ucounts->count += 1;
- }
- spin_unlock_irqrestore(&ucounts_lock, flags);
-
- return ucounts;
-}
-
-void put_ucounts(struct ucounts *ucounts)
+static void put_ucounts(struct ucounts *ucounts)
{
unsigned long flags;
@@ -227,7 +194,7 @@ struct ucounts *inc_ucount(struct user_n
{
struct ucounts *ucounts, *iter, *bad;
struct user_namespace *tns;
- ucounts = alloc_ucounts(ns, uid);
+ ucounts = get_ucounts(ns, uid);
for (iter = ucounts; iter; iter = tns->ucounts) {
int max;
tns = iter->ns;
@@ -270,7 +237,6 @@ static __init int user_namespace_sysctl_
BUG_ON(!user_header);
BUG_ON(!setup_userns_sysctls(&init_user_ns));
#endif
- hlist_add_ucounts(&init_ucounts);
return 0;
}
subsys_initcall(user_namespace_sysctl_init);
--- a/kernel/user_namespace.c
+++ b/kernel/user_namespace.c
@@ -1340,9 +1340,6 @@ static int userns_install(struct nsset *
put_user_ns(cred->user_ns);
set_cred_user_ns(cred, get_user_ns(user_ns));
- if (set_cred_ucounts(cred) < 0)
- return -EINVAL;
-
return 0;
}
next prev parent reply other threads:[~2021-09-06 12:57 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-06 12:55 [PATCH 5.10 00/29] 5.10.63-rc1 review Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 01/29] ext4: fix race writing to an inline_data file while its xattrs are changing Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 02/29] fscrypt: add fscrypt_symlink_getattr() for computing st_size Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 03/29] ext4: report correct st_size for encrypted symlinks Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 04/29] f2fs: " Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 05/29] ubifs: " Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 06/29] Revert "ucounts: Increase ucounts reference counter before the security hook" Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 07/29] Revert "cred: add missing return error code when set_cred_ucounts() failed" Greg Kroah-Hartman
2021-09-06 12:55 ` Greg Kroah-Hartman [this message]
2021-09-06 12:55 ` [PATCH 5.10 09/29] static_call: Fix unused variable warn w/o MODULE Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 10/29] xtensa: fix kconfig unmet dependency warning for HAVE_FUTEX_CMPXCHG Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 11/29] ARM: OMAP1: ams-delta: remove unused function ams_delta_camera_power Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 12/29] gpu: ipu-v3: Fix i.MX IPU-v3 offset calculations for (semi)planar U/V formats Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 13/29] reset: reset-zynqmp: Fixed the argument data type Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 14/29] qed: Fix the VF msix vectors flow Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 15/29] net: macb: Add a NULL check on desc_ptp Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 16/29] qede: Fix memset corruption Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 17/29] perf/x86/intel/pt: Fix mask of num_address_ranges Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 18/29] ceph: fix possible null-pointer dereference in ceph_mdsmap_decode() Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 19/29] perf/x86/amd/ibs: Work around erratum #1197 Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 20/29] perf/x86/amd/power: Assign pmu.module Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 21/29] cryptoloop: add a deprecation warning Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 22/29] ALSA: hda/realtek: Quirk for HP Spectre x360 14 amp setup Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 23/29] ALSA: hda/realtek: Workaround for conflicting SSID on ASUS ROG Strix G17 Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 24/29] ALSA: pcm: fix divide error in snd_pcm_lib_ioctl Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 25/29] serial: 8250: 8250_omap: Fix possible array out of bounds access Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 26/29] spi: Switch to signed types for *_native_cs SPI controller fields Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 27/29] new helper: inode_wrong_type() Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 28/29] fuse: fix illegal access to inode with reused nodeid Greg Kroah-Hartman
2021-09-06 12:55 ` [PATCH 5.10 29/29] media: stkwebcam: fix memory leak in stk_camera_probe Greg Kroah-Hartman
2021-09-06 19:58 ` [PATCH 5.10 00/29] 5.10.63-rc1 review Pavel Machek
2021-09-06 19:58 ` Fox Chen
2021-09-07 7:10 ` Naresh Kamboju
2021-09-07 7:11 ` Samuel Zou
2021-09-07 13:12 ` Sudip Mukherjee
2021-09-07 15:53 ` Jon Hunter
2021-09-07 18:34 ` Florian Fainelli
2021-09-07 20:07 ` Shuah Khan
2021-09-08 1:19 ` Guenter Roeck
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