* [PATCH v5 12/23] LSM: Use lsmblob in security_inode_getsecid
From: Casey Schaufler @ 2019-07-03 21:25 UTC (permalink / raw)
To: casey.schaufler, jmorris, linux-security-module, selinux
Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190703212538.7383-1-casey@schaufler-ca.com>
Change the security_inode_getsecid() interface to fill in a
lsmblob structure instead of a u32 secid. This allows for its
callers to gather data from all registered LSMs. Data is provided
for IMA and audit.
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
include/linux/security.h | 7 ++++---
kernel/auditsc.c | 6 +++++-
security/integrity/ima/ima_policy.c | 4 +---
security/security.c | 11 +++++++++--
4 files changed, 19 insertions(+), 9 deletions(-)
diff --git a/include/linux/security.h b/include/linux/security.h
index cfd7cf4b0be9..2d81cac418e3 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -362,7 +362,7 @@ int security_inode_killpriv(struct dentry *dentry);
int security_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc);
int security_inode_setsecurity(struct inode *inode, const char *name, const void *value, size_t size, int flags);
int security_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size);
-void security_inode_getsecid(struct inode *inode, u32 *secid);
+void security_inode_getsecid(struct inode *inode, struct lsmblob *blob);
int security_inode_copy_up(struct dentry *src, struct cred **new);
int security_inode_copy_up_xattr(const char *name);
int security_file_permission(struct file *file, int mask);
@@ -858,9 +858,10 @@ static inline int security_inode_listsecurity(struct inode *inode, char *buffer,
return 0;
}
-static inline void security_inode_getsecid(struct inode *inode, u32 *secid)
+static inline void security_inode_getsecid(struct inode *inode,
+ struct lsmblob *blob)
{
- *secid = 0;
+ lsmblob_init(blob, 0);
}
static inline int security_inode_copy_up(struct dentry *src, struct cred **new)
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 7112fe31684d..54797c0fc3b7 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1910,13 +1910,17 @@ static inline int audit_copy_fcaps(struct audit_names *name,
void audit_copy_inode(struct audit_names *name, const struct dentry *dentry,
struct inode *inode, unsigned int flags)
{
+ struct lsmblob blob;
+
name->ino = inode->i_ino;
name->dev = inode->i_sb->s_dev;
name->mode = inode->i_mode;
name->uid = inode->i_uid;
name->gid = inode->i_gid;
name->rdev = inode->i_rdev;
- security_inode_getsecid(inode, &name->osid);
+ security_inode_getsecid(inode, &blob);
+ /* scaffolding until osid is updated */
+ name->osid = blob.secid[0];
if (flags & AUDIT_INODE_NOEVAL) {
name->fcap_ver = -1;
return;
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index e7b8ce942950..92ee3d984c73 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -326,7 +326,6 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
return false;
for (i = 0; i < MAX_LSM_RULES; i++) {
int rc = 0;
- u32 osid;
struct lsmblob blob;
int retried = 0;
@@ -337,8 +336,7 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
case LSM_OBJ_USER:
case LSM_OBJ_ROLE:
case LSM_OBJ_TYPE:
- security_inode_getsecid(inode, &osid);
- lsmblob_init(&blob, osid);
+ security_inode_getsecid(inode, &blob);
rc = security_filter_rule_match(&blob,
rule->lsm[i].type,
Audit_equal,
diff --git a/security/security.c b/security/security.c
index 43076ae0373f..745e8791b6e3 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1404,9 +1404,16 @@ int security_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer
}
EXPORT_SYMBOL(security_inode_listsecurity);
-void security_inode_getsecid(struct inode *inode, u32 *secid)
+void security_inode_getsecid(struct inode *inode, struct lsmblob *blob)
{
- call_void_hook(inode_getsecid, inode, secid);
+ struct security_hook_list *hp;
+
+ lsmblob_init(blob, 0);
+ hlist_for_each_entry(hp, &security_hook_heads.inode_getsecid, list) {
+ if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
+ continue;
+ hp->hook.inode_getsecid(inode, &blob->secid[hp->lsmid->slot]);
+ }
}
int security_inode_copy_up(struct dentry *src, struct cred **new)
--
2.20.1
^ permalink raw reply related
* [PATCH v5 13/23] LSM: Use lsmblob in security_cred_getsecid
From: Casey Schaufler @ 2019-07-03 21:25 UTC (permalink / raw)
To: casey.schaufler, jmorris, linux-security-module, selinux
Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190703212538.7383-1-casey@schaufler-ca.com>
Change the security_cred_getsecid() interface to fill in a
lsmblob instead of a u32 secid. The associated data elements
in the audit sub-system are changed from a secid to a lsmblob
to accommodate multiple possible LSM audit users.
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
include/linux/security.h | 2 +-
kernel/audit.c | 14 +++++-------
kernel/audit.h | 5 +++--
kernel/auditsc.c | 37 +++++++++++--------------------
security/integrity/ima/ima_main.c | 8 +++----
security/security.c | 12 +++++++---
6 files changed, 36 insertions(+), 42 deletions(-)
diff --git a/include/linux/security.h b/include/linux/security.h
index 2d81cac418e3..d310fa3942ce 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -387,7 +387,7 @@ int security_cred_alloc_blank(struct cred *cred, gfp_t gfp);
void security_cred_free(struct cred *cred);
int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp);
void security_transfer_creds(struct cred *new, const struct cred *old);
-void security_cred_getsecid(const struct cred *c, u32 *secid);
+void security_cred_getsecid(const struct cred *c, struct lsmblob *blob);
int security_kernel_act_as(struct cred *new, struct lsmblob *blob);
int security_kernel_create_files_as(struct cred *new, struct inode *inode);
int security_kernel_module_request(char *kmod_name);
diff --git a/kernel/audit.c b/kernel/audit.c
index a0205f3c23c7..1b51e907f131 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -137,7 +137,7 @@ static u32 audit_backlog_wait_time = AUDIT_BACKLOG_WAIT_TIME;
/* The identity of the user shutting down the audit system. */
kuid_t audit_sig_uid = INVALID_UID;
pid_t audit_sig_pid = -1;
-u32 audit_sig_sid = 0;
+struct lsmblob audit_sig_lsm;
/* Records can be lost in several ways:
0) [suppressed in audit_alloc]
@@ -1429,23 +1429,21 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
}
case AUDIT_SIGNAL_INFO:
len = 0;
- if (audit_sig_sid) {
- struct lsmblob blob;
-
- lsmblob_init(&blob, audit_sig_sid);
- err = security_secid_to_secctx(&blob, &ctx, &len);
+ if (lsmblob_is_set(&audit_sig_lsm)) {
+ err = security_secid_to_secctx(&audit_sig_lsm, &ctx,
+ &len);
if (err)
return err;
}
sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
if (!sig_data) {
- if (audit_sig_sid)
+ if (lsmblob_is_set(&audit_sig_lsm))
security_release_secctx(ctx, len);
return -ENOMEM;
}
sig_data->uid = from_kuid(&init_user_ns, audit_sig_uid);
sig_data->pid = audit_sig_pid;
- if (audit_sig_sid) {
+ if (lsmblob_is_set(&audit_sig_lsm)) {
memcpy(sig_data->ctx, ctx, len);
security_release_secctx(ctx, len);
}
diff --git a/kernel/audit.h b/kernel/audit.h
index 958d5b8fc1b3..29e29c6f4afb 100644
--- a/kernel/audit.h
+++ b/kernel/audit.h
@@ -22,6 +22,7 @@
#include <linux/fs.h>
#include <linux/audit.h>
#include <linux/skbuff.h>
+#include <linux/security.h>
#include <uapi/linux/mqueue.h>
#include <linux/tty.h>
@@ -147,7 +148,7 @@ struct audit_context {
kuid_t target_auid;
kuid_t target_uid;
unsigned int target_sessionid;
- u32 target_sid;
+ struct lsmblob target_lsm;
char target_comm[TASK_COMM_LEN];
struct audit_tree_refs *trees, *first_trees;
@@ -338,7 +339,7 @@ extern char *audit_unpack_string(void **bufp, size_t *remain, size_t len);
extern pid_t audit_sig_pid;
extern kuid_t audit_sig_uid;
-extern u32 audit_sig_sid;
+extern struct lsmblob audit_sig_lsm;
extern int audit_filter(int msgtype, unsigned int listtype);
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 54797c0fc3b7..c7aa39bda5cc 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -112,7 +112,7 @@ struct audit_aux_data_pids {
kuid_t target_auid[AUDIT_AUX_PIDS];
kuid_t target_uid[AUDIT_AUX_PIDS];
unsigned int target_sessionid[AUDIT_AUX_PIDS];
- u32 target_sid[AUDIT_AUX_PIDS];
+ struct lsmblob target_lsm[AUDIT_AUX_PIDS];
char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
int pid_count;
};
@@ -938,14 +938,14 @@ static inline void audit_free_context(struct audit_context *context)
}
static int audit_log_pid_context(struct audit_context *context, pid_t pid,
- kuid_t auid, kuid_t uid, unsigned int sessionid,
- u32 sid, char *comm)
+ kuid_t auid, kuid_t uid,
+ unsigned int sessionid,
+ struct lsmblob *blob, char *comm)
{
struct audit_buffer *ab;
char *ctx = NULL;
u32 len;
int rc = 0;
- struct lsmblob blob;
ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
if (!ab)
@@ -954,9 +954,8 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
from_kuid(&init_user_ns, auid),
from_kuid(&init_user_ns, uid), sessionid);
- if (sid) {
- lsmblob_init(&blob, sid);
- if (security_secid_to_secctx(&blob, &ctx, &len)) {
+ if (lsmblob_is_set(blob)) {
+ if (security_secid_to_secctx(blob, &ctx, &len)) {
audit_log_format(ab, " obj=(none)");
rc = 1;
} else {
@@ -1527,7 +1526,7 @@ static void audit_log_exit(void)
axs->target_auid[i],
axs->target_uid[i],
axs->target_sessionid[i],
- axs->target_sid[i],
+ &axs->target_lsm[i],
axs->target_comm[i]))
call_panic = 1;
}
@@ -1536,7 +1535,7 @@ static void audit_log_exit(void)
audit_log_pid_context(context, context->target_pid,
context->target_auid, context->target_uid,
context->target_sessionid,
- context->target_sid, context->target_comm))
+ &context->target_lsm, context->target_comm))
call_panic = 1;
if (context->pwd.dentry && context->pwd.mnt) {
@@ -1713,7 +1712,7 @@ void __audit_syscall_exit(int success, long return_code)
context->aux = NULL;
context->aux_pids = NULL;
context->target_pid = 0;
- context->target_sid = 0;
+ lsmblob_init(&context->target_lsm, 0);
context->sockaddr_len = 0;
context->type = 0;
context->fds[0] = -1;
@@ -2367,15 +2366,12 @@ int __audit_sockaddr(int len, void *a)
void __audit_ptrace(struct task_struct *t)
{
struct audit_context *context = audit_context();
- struct lsmblob blob;
context->target_pid = task_tgid_nr(t);
context->target_auid = audit_get_loginuid(t);
context->target_uid = task_uid(t);
context->target_sessionid = audit_get_sessionid(t);
- security_task_getsecid(t, &blob);
- /* scaffolding - until target_sid is converted */
- context->target_sid = blob.secid[0];
+ security_task_getsecid(t, &context->target_lsm);
memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
}
@@ -2392,7 +2388,6 @@ int audit_signal_info(int sig, struct task_struct *t)
struct audit_aux_data_pids *axp;
struct audit_context *ctx = audit_context();
kuid_t uid = current_uid(), auid, t_uid = task_uid(t);
- struct lsmblob blob;
if (auditd_test_task(t) &&
(sig == SIGTERM || sig == SIGHUP ||
@@ -2403,9 +2398,7 @@ int audit_signal_info(int sig, struct task_struct *t)
audit_sig_uid = auid;
else
audit_sig_uid = uid;
- security_task_getsecid(current, &blob);
- /* scaffolding until audit_sig_sid is converted */
- audit_sig_sid = blob.secid[0];
+ security_task_getsecid(current, &audit_sig_lsm);
}
if (!audit_signals || audit_dummy_context())
@@ -2418,9 +2411,7 @@ int audit_signal_info(int sig, struct task_struct *t)
ctx->target_auid = audit_get_loginuid(t);
ctx->target_uid = t_uid;
ctx->target_sessionid = audit_get_sessionid(t);
- security_task_getsecid(t, &blob);
- /* scaffolding until target_sid is converted */
- ctx->target_sid = blob.secid[0];
+ security_task_getsecid(t, &ctx->target_lsm);
memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
return 0;
}
@@ -2441,9 +2432,7 @@ int audit_signal_info(int sig, struct task_struct *t)
axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
axp->target_uid[axp->pid_count] = t_uid;
axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
- security_task_getsecid(t, &blob);
- /* scaffolding until target_sid is converted */
- axp->target_sid[axp->pid_count] = blob.secid[0];
+ security_task_getsecid(t, &axp->target_lsm[axp->pid_count]);
memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
axp->pid_count++;
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index fefa848cf0c7..1afb75a893af 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -363,7 +363,6 @@ int ima_file_mmap(struct file *file, unsigned long prot)
int ima_bprm_check(struct linux_binprm *bprm)
{
int ret;
- u32 secid;
struct lsmblob blob;
security_task_getsecid(current, &blob);
@@ -373,9 +372,10 @@ int ima_bprm_check(struct linux_binprm *bprm)
if (ret)
return ret;
- security_cred_getsecid(bprm->cred, &secid);
- return process_measurement(bprm->file, bprm->cred, secid, NULL, 0,
- MAY_EXEC, CREDS_CHECK);
+ security_cred_getsecid(bprm->cred, &blob);
+ /* scaffolding until process_measurement changes */
+ return process_measurement(bprm->file, bprm->cred, blob.secid[0],
+ NULL, 0, MAY_EXEC, CREDS_CHECK);
}
/**
diff --git a/security/security.c b/security/security.c
index 745e8791b6e3..8927508b2142 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1627,10 +1627,16 @@ void security_transfer_creds(struct cred *new, const struct cred *old)
call_void_hook(cred_transfer, new, old);
}
-void security_cred_getsecid(const struct cred *c, u32 *secid)
+void security_cred_getsecid(const struct cred *c, struct lsmblob *blob)
{
- *secid = 0;
- call_void_hook(cred_getsecid, c, secid);
+ struct security_hook_list *hp;
+
+ lsmblob_init(blob, 0);
+ hlist_for_each_entry(hp, &security_hook_heads.cred_getsecid, list) {
+ if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
+ continue;
+ hp->hook.cred_getsecid(c, &blob->secid[hp->lsmid->slot]);
+ }
}
EXPORT_SYMBOL(security_cred_getsecid);
--
2.20.1
^ permalink raw reply related
* [PATCH v5 09/23] LSM: Use lsmblob in security_secid_to_secctx
From: Casey Schaufler @ 2019-07-03 21:25 UTC (permalink / raw)
To: casey.schaufler, jmorris, linux-security-module, selinux
Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190703212538.7383-1-casey@schaufler-ca.com>
Change security_secid_to_secctx() to take a lsmblob as input
instead of a u32 secid. It will then call the LSM hooks
using the lsmblob element allocated for that module. The
callers have been updated as well. This allows for the
possibility that more than one module may be called upon
to translate a secid to a string, as can occur in the
audit code.
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
drivers/android/binder.c | 4 +++-
include/linux/security.h | 5 +++--
include/net/scm.h | 5 ++---
kernel/audit.c | 9 +++++++--
kernel/auditsc.c | 14 ++++++++++----
net/ipv4/ip_sockglue.c | 3 +--
net/netfilter/nf_conntrack_netlink.c | 8 ++++++--
net/netfilter/nf_conntrack_standalone.c | 4 +++-
net/netfilter/nfnetlink_queue.c | 8 ++++++--
net/netlabel/netlabel_unlabeled.c | 18 ++++++++++++++----
net/netlabel/netlabel_user.c | 6 +++---
security/security.c | 16 +++++++++++++---
12 files changed, 71 insertions(+), 29 deletions(-)
diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 8685882da64c..1962f6b8abd0 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -3120,9 +3120,11 @@ static void binder_transaction(struct binder_proc *proc,
if (target_node && target_node->txn_security_ctx) {
u32 secid;
+ struct lsmblob blob;
security_task_getsecid(proc->tsk, &secid);
- ret = security_secid_to_secctx(secid, &secctx, &secctx_sz);
+ lsmblob_init(&blob, secid);
+ ret = security_secid_to_secctx(&blob, &secctx, &secctx_sz);
if (ret) {
return_error = BR_FAILED_REPLY;
return_error_param = ret;
diff --git a/include/linux/security.h b/include/linux/security.h
index 30337f1a9056..7b4667cc4930 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -446,7 +446,7 @@ int security_setprocattr(const char *lsm, const char *name, void *value,
size_t size);
int security_netlink_send(struct sock *sk, struct sk_buff *skb);
int security_ismaclabel(const char *name);
-int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen);
+int security_secid_to_secctx(struct lsmblob *blob, char **secdata, u32 *seclen);
int security_secctx_to_secid(const char *secdata, u32 seclen,
struct lsmblob *blob);
void security_release_secctx(char *secdata, u32 seclen);
@@ -1224,7 +1224,8 @@ static inline int security_ismaclabel(const char *name)
return 0;
}
-static inline int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
+static inline int security_secid_to_secctx(struct lsmblob *blob,
+ char **secdata, u32 *seclen)
{
return -EOPNOTSUPP;
}
diff --git a/include/net/scm.h b/include/net/scm.h
index e2e71c4bf9d0..31ae605fcc0a 100644
--- a/include/net/scm.h
+++ b/include/net/scm.h
@@ -97,9 +97,8 @@ static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct sc
int err;
if (test_bit(SOCK_PASSSEC, &sock->flags)) {
- /* Scaffolding - it has to be element 0 for now */
- err = security_secid_to_secctx(scm->lsmblob.secid[0],
- &secdata, &seclen);
+ err = security_secid_to_secctx(&scm->lsmblob, &secdata,
+ &seclen);
if (!err) {
put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
diff --git a/kernel/audit.c b/kernel/audit.c
index c89ea48c70a6..d0338411d75d 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -1430,7 +1430,10 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
case AUDIT_SIGNAL_INFO:
len = 0;
if (audit_sig_sid) {
- err = security_secid_to_secctx(audit_sig_sid, &ctx, &len);
+ struct lsmblob blob;
+
+ lsmblob_init(&blob, audit_sig_sid);
+ err = security_secid_to_secctx(&blob, &ctx, &len);
if (err)
return err;
}
@@ -2073,12 +2076,14 @@ int audit_log_task_context(struct audit_buffer *ab)
unsigned len;
int error;
u32 sid;
+ struct lsmblob blob;
security_task_getsecid(current, &sid);
if (!sid)
return 0;
- error = security_secid_to_secctx(sid, &ctx, &len);
+ lsmblob_init(&blob, sid);
+ error = security_secid_to_secctx(&blob, &ctx, &len);
if (error) {
if (error != -EINVAL)
goto error_path;
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 18ee5556c086..d31914088a82 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -947,6 +947,7 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
char *ctx = NULL;
u32 len;
int rc = 0;
+ struct lsmblob blob;
ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
if (!ab)
@@ -956,7 +957,8 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
from_kuid(&init_user_ns, auid),
from_kuid(&init_user_ns, uid), sessionid);
if (sid) {
- if (security_secid_to_secctx(sid, &ctx, &len)) {
+ lsmblob_init(&blob, sid);
+ if (security_secid_to_secctx(&blob, &ctx, &len)) {
audit_log_format(ab, " obj=(none)");
rc = 1;
} else {
@@ -1198,7 +1200,10 @@ static void show_special(struct audit_context *context, int *call_panic)
if (osid) {
char *ctx = NULL;
u32 len;
- if (security_secid_to_secctx(osid, &ctx, &len)) {
+ struct lsmblob blob;
+
+ lsmblob_init(&blob, osid);
+ if (security_secid_to_secctx(&blob, &ctx, &len)) {
audit_log_format(ab, " osid=%u", osid);
*call_panic = 1;
} else {
@@ -1349,9 +1354,10 @@ static void audit_log_name(struct audit_context *context, struct audit_names *n,
if (n->osid != 0) {
char *ctx = NULL;
u32 len;
+ struct lsmblob blob;
- if (security_secid_to_secctx(
- n->osid, &ctx, &len)) {
+ lsmblob_init(&blob, n->osid);
+ if (security_secid_to_secctx(&blob, &ctx, &len)) {
audit_log_format(ab, " osid=%u", n->osid);
if (call_panic)
*call_panic = 2;
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 2a5c868ce135..e05f4ef68bd8 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -139,8 +139,7 @@ static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
if (err)
return;
- /* Scaffolding - it has to be element 0 */
- err = security_secid_to_secctx(lb.secid[0], &secdata, &seclen);
+ err = security_secid_to_secctx(&lb, &secdata, &seclen);
if (err)
return;
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index 66c596d287a5..ca0968f13240 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -330,8 +330,10 @@ static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
struct nlattr *nest_secctx;
int len, ret;
char *secctx;
+ struct lsmblob blob;
- ret = security_secid_to_secctx(ct->secmark, &secctx, &len);
+ lsmblob_init(&blob, ct->secmark);
+ ret = security_secid_to_secctx(&blob, &secctx, &len);
if (ret)
return 0;
@@ -615,8 +617,10 @@ static inline int ctnetlink_secctx_size(const struct nf_conn *ct)
{
#ifdef CONFIG_NF_CONNTRACK_SECMARK
int len, ret;
+ struct lsmblob blob;
- ret = security_secid_to_secctx(ct->secmark, NULL, &len);
+ lsmblob_init(&blob, ct->secmark);
+ ret = security_secid_to_secctx(&blob, NULL, &len);
if (ret)
return 0;
diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c
index c2ae14c720b4..c793103f3cd7 100644
--- a/net/netfilter/nf_conntrack_standalone.c
+++ b/net/netfilter/nf_conntrack_standalone.c
@@ -175,8 +175,10 @@ static void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
int ret;
u32 len;
char *secctx;
+ struct lsmblob blob;
- ret = security_secid_to_secctx(ct->secmark, &secctx, &len);
+ lsmblob_init(&blob, ct->secmark);
+ ret = security_secid_to_secctx(&blob, &secctx, &len);
if (ret)
return;
diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index 0dcc3592d053..59211bff90ab 100644
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -309,13 +309,17 @@ static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
{
u32 seclen = 0;
#if IS_ENABLED(CONFIG_NETWORK_SECMARK)
+ struct lsmblob blob;
+
if (!skb || !sk_fullsock(skb->sk))
return 0;
read_lock_bh(&skb->sk->sk_callback_lock);
- if (skb->secmark)
- security_secid_to_secctx(skb->secmark, secdata, &seclen);
+ if (skb->secmark) {
+ lsmblob_init(&blob, skb->secmark);
+ security_secid_to_secctx(&blob, secdata, &seclen);
+ }
read_unlock_bh(&skb->sk->sk_callback_lock);
#endif
diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
index 2976370e41aa..2d8dd5b84457 100644
--- a/net/netlabel/netlabel_unlabeled.c
+++ b/net/netlabel/netlabel_unlabeled.c
@@ -389,6 +389,7 @@ int netlbl_unlhsh_add(struct net *net,
struct audit_buffer *audit_buf = NULL;
char *secctx = NULL;
u32 secctx_len;
+ struct lsmblob blob;
if (addr_len != sizeof(struct in_addr) &&
addr_len != sizeof(struct in6_addr))
@@ -451,7 +452,8 @@ int netlbl_unlhsh_add(struct net *net,
unlhsh_add_return:
rcu_read_unlock();
if (audit_buf != NULL) {
- if (security_secid_to_secctx(secid,
+ lsmblob_init(&blob, secid);
+ if (security_secid_to_secctx(&blob,
&secctx,
&secctx_len) == 0) {
audit_log_format(audit_buf, " sec_obj=%s", secctx);
@@ -488,6 +490,7 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
struct net_device *dev;
char *secctx;
u32 secctx_len;
+ struct lsmblob blob;
spin_lock(&netlbl_unlhsh_lock);
list_entry = netlbl_af4list_remove(addr->s_addr, mask->s_addr,
@@ -507,8 +510,10 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
addr->s_addr, mask->s_addr);
if (dev != NULL)
dev_put(dev);
+ if (entry != NULL)
+ lsmblob_init(&blob, entry->secid);
if (entry != NULL &&
- security_secid_to_secctx(entry->secid,
+ security_secid_to_secctx(&blob,
&secctx, &secctx_len) == 0) {
audit_log_format(audit_buf, " sec_obj=%s", secctx);
security_release_secctx(secctx, secctx_len);
@@ -550,6 +555,7 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
struct net_device *dev;
char *secctx;
u32 secctx_len;
+ struct lsmblob blob;
spin_lock(&netlbl_unlhsh_lock);
list_entry = netlbl_af6list_remove(addr, mask, &iface->addr6_list);
@@ -568,8 +574,10 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
addr, mask);
if (dev != NULL)
dev_put(dev);
+ if (entry != NULL)
+ lsmblob_init(&blob, entry->secid);
if (entry != NULL &&
- security_secid_to_secctx(entry->secid,
+ security_secid_to_secctx(&blob,
&secctx, &secctx_len) == 0) {
audit_log_format(audit_buf, " sec_obj=%s", secctx);
security_release_secctx(secctx, secctx_len);
@@ -1090,6 +1098,7 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
u32 secid;
char *secctx;
u32 secctx_len;
+ struct lsmblob blob;
data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid,
cb_arg->seq, &netlbl_unlabel_gnl_family,
@@ -1144,7 +1153,8 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
secid = addr6->secid;
}
- ret_val = security_secid_to_secctx(secid, &secctx, &secctx_len);
+ lsmblob_init(&blob, secid);
+ ret_val = security_secid_to_secctx(&blob, &secctx, &secctx_len);
if (ret_val != 0)
goto list_cb_failure;
ret_val = nla_put(cb_arg->skb,
diff --git a/net/netlabel/netlabel_user.c b/net/netlabel/netlabel_user.c
index 4676f5bb16ae..2ccc6567e2a2 100644
--- a/net/netlabel/netlabel_user.c
+++ b/net/netlabel/netlabel_user.c
@@ -100,6 +100,7 @@ struct audit_buffer *netlbl_audit_start_common(int type,
struct audit_buffer *audit_buf;
char *secctx;
u32 secctx_len;
+ struct lsmblob blob;
if (audit_enabled == AUDIT_OFF)
return NULL;
@@ -112,10 +113,9 @@ struct audit_buffer *netlbl_audit_start_common(int type,
from_kuid(&init_user_ns, audit_info->loginuid),
audit_info->sessionid);
+ lsmblob_init(&blob, audit_info->secid);
if (audit_info->secid != 0 &&
- security_secid_to_secctx(audit_info->secid,
- &secctx,
- &secctx_len) == 0) {
+ security_secid_to_secctx(&blob, &secctx, &secctx_len) == 0) {
audit_log_format(audit_buf, " subj=%s", secctx);
security_release_secctx(secctx, secctx_len);
}
diff --git a/security/security.c b/security/security.c
index e231fbfd68f2..837c3c6b6e7c 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1975,10 +1975,20 @@ int security_ismaclabel(const char *name)
}
EXPORT_SYMBOL(security_ismaclabel);
-int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
+int security_secid_to_secctx(struct lsmblob *blob, char **secdata, u32 *seclen)
{
- return call_int_hook(secid_to_secctx, -EOPNOTSUPP, secid, secdata,
- seclen);
+ struct security_hook_list *hp;
+ int rc;
+
+ hlist_for_each_entry(hp, &security_hook_heads.secid_to_secctx, list) {
+ if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
+ continue;
+ rc = hp->hook.secid_to_secctx(blob->secid[hp->lsmid->slot],
+ secdata, seclen);
+ if (rc != 0)
+ return rc;
+ }
+ return 0;
}
EXPORT_SYMBOL(security_secid_to_secctx);
--
2.20.1
^ permalink raw reply related
* [PATCH v5 10/23] LSM: Use lsmblob in security_ipc_getsecid
From: Casey Schaufler @ 2019-07-03 21:25 UTC (permalink / raw)
To: casey.schaufler, jmorris, linux-security-module, selinux
Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190703212538.7383-1-casey@schaufler-ca.com>
There may be more than one LSM that provides IPC data
for auditing. Change security_ipc_getsecid() to fill in
a lsmblob structure instead of the u32 secid. The
audit data structure containing the secid will be updated
later, so there is a bit of scaffolding here.
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
include/linux/security.h | 7 ++++---
kernel/auditsc.c | 5 ++++-
security/security.c | 12 +++++++++---
3 files changed, 17 insertions(+), 7 deletions(-)
diff --git a/include/linux/security.h b/include/linux/security.h
index 7b4667cc4930..41dc3053094e 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -417,7 +417,7 @@ int security_task_prctl(int option, unsigned long arg2, unsigned long arg3,
unsigned long arg4, unsigned long arg5);
void security_task_to_inode(struct task_struct *p, struct inode *inode);
int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag);
-void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid);
+void security_ipc_getsecid(struct kern_ipc_perm *ipcp, struct lsmblob *blob);
int security_msg_msg_alloc(struct msg_msg *msg);
void security_msg_msg_free(struct msg_msg *msg);
int security_msg_queue_alloc(struct kern_ipc_perm *msq);
@@ -1102,9 +1102,10 @@ static inline int security_ipc_permission(struct kern_ipc_perm *ipcp,
return 0;
}
-static inline void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
+static inline void security_ipc_getsecid(struct kern_ipc_perm *ipcp,
+ struct lsmblob *blob)
{
- *secid = 0;
+ lsmblob_init(blob, 0);
}
static inline int security_msg_msg_alloc(struct msg_msg *msg)
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index d31914088a82..148733ec3c72 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -2268,11 +2268,14 @@ void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
{
struct audit_context *context = audit_context();
+ struct lsmblob blob;
context->ipc.uid = ipcp->uid;
context->ipc.gid = ipcp->gid;
context->ipc.mode = ipcp->mode;
context->ipc.has_perm = 0;
- security_ipc_getsecid(ipcp, &context->ipc.osid);
+ security_ipc_getsecid(ipcp, &blob);
+ /* scaffolding on the [0] - change "osid" to a lsmblob */
+ context->ipc.osid = blob.secid[0];
context->type = AUDIT_IPC;
}
diff --git a/security/security.c b/security/security.c
index 837c3c6b6e7c..b4789c31e532 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1795,10 +1795,16 @@ int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
return call_int_hook(ipc_permission, 0, ipcp, flag);
}
-void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
+void security_ipc_getsecid(struct kern_ipc_perm *ipcp, struct lsmblob *blob)
{
- *secid = 0;
- call_void_hook(ipc_getsecid, ipcp, secid);
+ struct security_hook_list *hp;
+
+ lsmblob_init(blob, 0);
+ hlist_for_each_entry(hp, &security_hook_heads.ipc_getsecid, list) {
+ if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
+ continue;
+ hp->hook.ipc_getsecid(ipcp, &blob->secid[hp->lsmid->slot]);
+ }
}
int security_msg_msg_alloc(struct msg_msg *msg)
--
2.20.1
^ permalink raw reply related
* [PATCH v5 08/23] LSM: Use lsmblob in security_secctx_to_secid
From: Casey Schaufler @ 2019-07-03 21:25 UTC (permalink / raw)
To: casey.schaufler, jmorris, linux-security-module, selinux
Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190703212538.7383-1-casey@schaufler-ca.com>
Change security_secctx_to_secid() to fill in a lsmblob instead
of a u32 secid. Multiple LSMs may be able to interpret the
string, and this allows for setting whichever secid is
appropriate. In some cases there is scaffolding where other
interfaces have yet to be converted.
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
include/linux/security.h | 5 +++--
kernel/cred.c | 4 +---
net/netfilter/nft_meta.c | 13 ++++++-------
net/netfilter/xt_SECMARK.c | 5 ++++-
net/netlabel/netlabel_unlabeled.c | 14 ++++++++------
security/security.c | 18 +++++++++++++++---
6 files changed, 37 insertions(+), 22 deletions(-)
diff --git a/include/linux/security.h b/include/linux/security.h
index dcf20da87d1b..30337f1a9056 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -447,7 +447,8 @@ int security_setprocattr(const char *lsm, const char *name, void *value,
int security_netlink_send(struct sock *sk, struct sk_buff *skb);
int security_ismaclabel(const char *name);
int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen);
-int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid);
+int security_secctx_to_secid(const char *secdata, u32 seclen,
+ struct lsmblob *blob);
void security_release_secctx(char *secdata, u32 seclen);
void security_inode_invalidate_secctx(struct inode *inode);
@@ -1230,7 +1231,7 @@ static inline int security_secid_to_secctx(u32 secid, char **secdata, u32 *secle
static inline int security_secctx_to_secid(const char *secdata,
u32 seclen,
- u32 *secid)
+ struct lsmblob *blob)
{
return -EOPNOTSUPP;
}
diff --git a/kernel/cred.c b/kernel/cred.c
index 71c14dda107e..d70a2c02ced4 100644
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -725,14 +725,12 @@ EXPORT_SYMBOL(set_security_override);
int set_security_override_from_ctx(struct cred *new, const char *secctx)
{
struct lsmblob blob;
- u32 secid;
int ret;
- ret = security_secctx_to_secid(secctx, strlen(secctx), &secid);
+ ret = security_secctx_to_secid(secctx, strlen(secctx), &blob);
if (ret < 0)
return ret;
- lsmblob_init(&blob, secid);
return set_security_override(new, &blob);
}
EXPORT_SYMBOL(set_security_override_from_ctx);
diff --git a/net/netfilter/nft_meta.c b/net/netfilter/nft_meta.c
index 987d2d6ce624..054fb4b48d51 100644
--- a/net/netfilter/nft_meta.c
+++ b/net/netfilter/nft_meta.c
@@ -576,21 +576,20 @@ static const struct nla_policy nft_secmark_policy[NFTA_SECMARK_MAX + 1] = {
static int nft_secmark_compute_secid(struct nft_secmark *priv)
{
- u32 tmp_secid = 0;
+ struct lsmblob blob;
int err;
- err = security_secctx_to_secid(priv->ctx, strlen(priv->ctx), &tmp_secid);
+ err = security_secctx_to_secid(priv->ctx, strlen(priv->ctx), &blob);
if (err)
return err;
- if (!tmp_secid)
- return -ENOENT;
-
- err = security_secmark_relabel_packet(tmp_secid);
+ /* Using le[0] is scaffolding */
+ err = security_secmark_relabel_packet(blob.secid[0]);
if (err)
return err;
- priv->secid = tmp_secid;
+ /* Using le[0] is scaffolding */
+ priv->secid = blob.secid[0];
return 0;
}
diff --git a/net/netfilter/xt_SECMARK.c b/net/netfilter/xt_SECMARK.c
index f16202d26c20..8081fadc30e9 100644
--- a/net/netfilter/xt_SECMARK.c
+++ b/net/netfilter/xt_SECMARK.c
@@ -49,13 +49,14 @@ secmark_tg(struct sk_buff *skb, const struct xt_action_param *par)
static int checkentry_lsm(struct xt_secmark_target_info *info)
{
+ struct lsmblob blob;
int err;
info->secctx[SECMARK_SECCTX_MAX - 1] = '\0';
info->secid = 0;
err = security_secctx_to_secid(info->secctx, strlen(info->secctx),
- &info->secid);
+ &blob);
if (err) {
if (err == -EINVAL)
pr_info_ratelimited("invalid security context \'%s\'\n",
@@ -63,6 +64,8 @@ static int checkentry_lsm(struct xt_secmark_target_info *info)
return err;
}
+ /* scaffolding during the transition */
+ info->secid = blob.secid[0];
if (!info->secid) {
pr_info_ratelimited("unable to map security context \'%s\'\n",
info->secctx);
diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
index c92894c3e40a..2976370e41aa 100644
--- a/net/netlabel/netlabel_unlabeled.c
+++ b/net/netlabel/netlabel_unlabeled.c
@@ -895,7 +895,7 @@ static int netlbl_unlabel_staticadd(struct sk_buff *skb,
void *addr;
void *mask;
u32 addr_len;
- u32 secid;
+ struct lsmblob blob;
struct netlbl_audit audit_info;
/* Don't allow users to add both IPv4 and IPv6 addresses for a
@@ -919,12 +919,13 @@ static int netlbl_unlabel_staticadd(struct sk_buff *skb,
ret_val = security_secctx_to_secid(
nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]),
nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]),
- &secid);
+ &blob);
if (ret_val != 0)
return ret_val;
+ /* scaffolding with the [0] */
return netlbl_unlhsh_add(&init_net,
- dev_name, addr, mask, addr_len, secid,
+ dev_name, addr, mask, addr_len, blob.secid[0],
&audit_info);
}
@@ -946,7 +947,7 @@ static int netlbl_unlabel_staticadddef(struct sk_buff *skb,
void *addr;
void *mask;
u32 addr_len;
- u32 secid;
+ struct lsmblob blob;
struct netlbl_audit audit_info;
/* Don't allow users to add both IPv4 and IPv6 addresses for a
@@ -968,12 +969,13 @@ static int netlbl_unlabel_staticadddef(struct sk_buff *skb,
ret_val = security_secctx_to_secid(
nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]),
nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]),
- &secid);
+ &blob);
if (ret_val != 0)
return ret_val;
+ /* scaffolding with the [0] */
return netlbl_unlhsh_add(&init_net,
- NULL, addr, mask, addr_len, secid,
+ NULL, addr, mask, addr_len, blob.secid[0],
&audit_info);
}
diff --git a/security/security.c b/security/security.c
index fe76dfa0f2fd..e231fbfd68f2 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1982,10 +1982,22 @@ int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
}
EXPORT_SYMBOL(security_secid_to_secctx);
-int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
+int security_secctx_to_secid(const char *secdata, u32 seclen,
+ struct lsmblob *blob)
{
- *secid = 0;
- return call_int_hook(secctx_to_secid, 0, secdata, seclen, secid);
+ struct security_hook_list *hp;
+ int rc;
+
+ lsmblob_init(blob, 0);
+ hlist_for_each_entry(hp, &security_hook_heads.secctx_to_secid, list) {
+ if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
+ continue;
+ rc = hp->hook.secctx_to_secid(secdata, seclen,
+ &blob->secid[hp->lsmid->slot]);
+ if (rc != 0)
+ return rc;
+ }
+ return 0;
}
EXPORT_SYMBOL(security_secctx_to_secid);
--
2.20.1
^ permalink raw reply related
* [PATCH v5 07/23] net: Prepare UDS for secuirty module stacking
From: Casey Schaufler @ 2019-07-03 21:25 UTC (permalink / raw)
To: casey.schaufler, jmorris, linux-security-module, selinux
Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190703212538.7383-1-casey@schaufler-ca.com>
Change the data used in UDS SO_PEERSEC processing from a
secid to a more general struct lsmblob. Update the
security_socket_getpeersec_dgram() interface to use the
lsmblob. There is a small amount of scaffolding code
that will come out when the security_secid_to_secctx()
code is brought in line with the lsmblob.
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
include/linux/security.h | 7 +++++--
include/net/af_unix.h | 2 +-
include/net/scm.h | 8 +++++---
net/ipv4/ip_sockglue.c | 8 +++++---
net/unix/af_unix.c | 6 +++---
security/security.c | 18 +++++++++++++++---
6 files changed, 34 insertions(+), 15 deletions(-)
diff --git a/include/linux/security.h b/include/linux/security.h
index 313e45a3cac3..dcf20da87d1b 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -1280,7 +1280,8 @@ int security_socket_shutdown(struct socket *sock, int how);
int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb);
int security_socket_getpeersec_stream(struct socket *sock, char __user *optval,
int __user *optlen, unsigned len);
-int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid);
+int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb,
+ struct lsmblob *blob);
int security_sk_alloc(struct sock *sk, int family, gfp_t priority);
void security_sk_free(struct sock *sk);
void security_sk_clone(const struct sock *sk, struct sock *newsk);
@@ -1418,7 +1419,9 @@ static inline int security_socket_getpeersec_stream(struct socket *sock, char __
return -ENOPROTOOPT;
}
-static inline int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
+static inline int security_socket_getpeersec_dgram(struct socket *sock,
+ struct sk_buff *skb,
+ struct lsmblob *blob)
{
return -ENOPROTOOPT;
}
diff --git a/include/net/af_unix.h b/include/net/af_unix.h
index 3426d6dacc45..933492c08b8c 100644
--- a/include/net/af_unix.h
+++ b/include/net/af_unix.h
@@ -36,7 +36,7 @@ struct unix_skb_parms {
kgid_t gid;
struct scm_fp_list *fp; /* Passed files */
#ifdef CONFIG_SECURITY_NETWORK
- u32 secid; /* Security ID */
+ struct lsmblob lsmblob; /* Security LSM data */
#endif
u32 consumed;
} __randomize_layout;
diff --git a/include/net/scm.h b/include/net/scm.h
index 1ce365f4c256..e2e71c4bf9d0 100644
--- a/include/net/scm.h
+++ b/include/net/scm.h
@@ -33,7 +33,7 @@ struct scm_cookie {
struct scm_fp_list *fp; /* Passed files */
struct scm_creds creds; /* Skb credentials */
#ifdef CONFIG_SECURITY_NETWORK
- u32 secid; /* Passed security ID */
+ struct lsmblob lsmblob; /* Passed LSM data */
#endif
};
@@ -46,7 +46,7 @@ struct scm_fp_list *scm_fp_dup(struct scm_fp_list *fpl);
#ifdef CONFIG_SECURITY_NETWORK
static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
{
- security_socket_getpeersec_dgram(sock, NULL, &scm->secid);
+ security_socket_getpeersec_dgram(sock, NULL, &scm->lsmblob);
}
#else
static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
@@ -97,7 +97,9 @@ static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct sc
int err;
if (test_bit(SOCK_PASSSEC, &sock->flags)) {
- err = security_secid_to_secctx(scm->secid, &secdata, &seclen);
+ /* Scaffolding - it has to be element 0 for now */
+ err = security_secid_to_secctx(scm->lsmblob.secid[0],
+ &secdata, &seclen);
if (!err) {
put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 82f341e84fae..2a5c868ce135 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -130,15 +130,17 @@ static void ip_cmsg_recv_checksum(struct msghdr *msg, struct sk_buff *skb,
static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
{
+ struct lsmblob lb;
char *secdata;
- u32 seclen, secid;
+ u32 seclen;
int err;
- err = security_socket_getpeersec_dgram(NULL, skb, &secid);
+ err = security_socket_getpeersec_dgram(NULL, skb, &lb);
if (err)
return;
- err = security_secid_to_secctx(secid, &secdata, &seclen);
+ /* Scaffolding - it has to be element 0 */
+ err = security_secid_to_secctx(lb.secid[0], &secdata, &seclen);
if (err)
return;
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index ddb838a1b74c..c50a004a1389 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -143,17 +143,17 @@ static struct hlist_head *unix_sockets_unbound(void *addr)
#ifdef CONFIG_SECURITY_NETWORK
static void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb)
{
- UNIXCB(skb).secid = scm->secid;
+ UNIXCB(skb).lsmblob = scm->lsmblob;
}
static inline void unix_set_secdata(struct scm_cookie *scm, struct sk_buff *skb)
{
- scm->secid = UNIXCB(skb).secid;
+ scm->lsmblob = UNIXCB(skb).lsmblob;
}
static inline bool unix_secdata_eq(struct scm_cookie *scm, struct sk_buff *skb)
{
- return (scm->secid == UNIXCB(skb).secid);
+ return lsmblob_equal(&scm->lsmblob, &(UNIXCB(skb).lsmblob));
}
#else
static inline void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb)
diff --git a/security/security.c b/security/security.c
index fa7ab1334f22..fe76dfa0f2fd 100644
--- a/security/security.c
+++ b/security/security.c
@@ -2120,10 +2120,22 @@ int security_socket_getpeersec_stream(struct socket *sock, char __user *optval,
optval, optlen, len);
}
-int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
+int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb,
+ struct lsmblob *blob)
{
- return call_int_hook(socket_getpeersec_dgram, -ENOPROTOOPT, sock,
- skb, secid);
+ struct security_hook_list *hp;
+ int rc = -ENOPROTOOPT;
+
+ hlist_for_each_entry(hp, &security_hook_heads.socket_getpeersec_dgram,
+ list) {
+ if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
+ continue;
+ rc = hp->hook.socket_getpeersec_dgram(sock, skb,
+ &blob->secid[hp->lsmid->slot]);
+ if (rc != 0)
+ break;
+ }
+ return rc;
}
EXPORT_SYMBOL(security_socket_getpeersec_dgram);
--
2.20.1
^ permalink raw reply related
* [PATCH v5 06/23] LSM: Use lsmblob in security_kernel_act_as
From: Casey Schaufler @ 2019-07-03 21:25 UTC (permalink / raw)
To: casey.schaufler, jmorris, linux-security-module, selinux
Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190703212538.7383-1-casey@schaufler-ca.com>
Change the security_kernel_act_as interface to use a lsmblob
structure in place of the single u32 secid in support of
module stacking. Change it's only caller, set_security_override,
to do the same. Change that one's only caller,
set_security_override_from_ctx, to call it with the new
parameter type.
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
include/linux/cred.h | 3 ++-
include/linux/security.h | 5 +++--
kernel/cred.c | 10 ++++++----
security/security.c | 14 ++++++++++++--
4 files changed, 23 insertions(+), 9 deletions(-)
diff --git a/include/linux/cred.h b/include/linux/cred.h
index efb6edf32de7..9a21c376ed97 100644
--- a/include/linux/cred.h
+++ b/include/linux/cred.h
@@ -22,6 +22,7 @@
struct cred;
struct inode;
+struct lsmblob;
/*
* COW Supplementary groups list
@@ -165,7 +166,7 @@ extern const struct cred *override_creds(const struct cred *);
extern void revert_creds(const struct cred *);
extern struct cred *prepare_kernel_cred(struct task_struct *);
extern int change_create_files_as(struct cred *, struct inode *);
-extern int set_security_override(struct cred *, u32);
+extern int set_security_override(struct cred *, struct lsmblob *);
extern int set_security_override_from_ctx(struct cred *, const char *);
extern int set_create_files_as(struct cred *, struct inode *);
extern int cred_fscmp(const struct cred *, const struct cred *);
diff --git a/include/linux/security.h b/include/linux/security.h
index 4f8b478bc3a1..313e45a3cac3 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -388,7 +388,7 @@ void security_cred_free(struct cred *cred);
int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp);
void security_transfer_creds(struct cred *new, const struct cred *old);
void security_cred_getsecid(const struct cred *c, u32 *secid);
-int security_kernel_act_as(struct cred *new, u32 secid);
+int security_kernel_act_as(struct cred *new, struct lsmblob *blob);
int security_kernel_create_files_as(struct cred *new, struct inode *inode);
int security_kernel_module_request(char *kmod_name);
int security_kernel_load_data(enum kernel_load_data_id id);
@@ -971,7 +971,8 @@ static inline void security_transfer_creds(struct cred *new,
{
}
-static inline int security_kernel_act_as(struct cred *cred, u32 secid)
+static inline int security_kernel_act_as(struct cred *cred,
+ struct lsmblob *blob)
{
return 0;
}
diff --git a/kernel/cred.c b/kernel/cred.c
index 45d77284aed0..71c14dda107e 100644
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -701,14 +701,14 @@ EXPORT_SYMBOL(prepare_kernel_cred);
/**
* set_security_override - Set the security ID in a set of credentials
* @new: The credentials to alter
- * @secid: The LSM security ID to set
+ * @blob: The LSM security information to set
*
* Set the LSM security ID in a set of credentials so that the subjective
* security is overridden when an alternative set of credentials is used.
*/
-int set_security_override(struct cred *new, u32 secid)
+int set_security_override(struct cred *new, struct lsmblob *blob)
{
- return security_kernel_act_as(new, secid);
+ return security_kernel_act_as(new, blob);
}
EXPORT_SYMBOL(set_security_override);
@@ -724,6 +724,7 @@ EXPORT_SYMBOL(set_security_override);
*/
int set_security_override_from_ctx(struct cred *new, const char *secctx)
{
+ struct lsmblob blob;
u32 secid;
int ret;
@@ -731,7 +732,8 @@ int set_security_override_from_ctx(struct cred *new, const char *secctx)
if (ret < 0)
return ret;
- return set_security_override(new, secid);
+ lsmblob_init(&blob, secid);
+ return set_security_override(new, &blob);
}
EXPORT_SYMBOL(set_security_override_from_ctx);
diff --git a/security/security.c b/security/security.c
index fa6e425e6f29..fa7ab1334f22 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1627,9 +1627,19 @@ void security_cred_getsecid(const struct cred *c, u32 *secid)
}
EXPORT_SYMBOL(security_cred_getsecid);
-int security_kernel_act_as(struct cred *new, u32 secid)
+int security_kernel_act_as(struct cred *new, struct lsmblob *blob)
{
- return call_int_hook(kernel_act_as, 0, new, secid);
+ struct security_hook_list *hp;
+ int rc;
+
+ hlist_for_each_entry(hp, &security_hook_heads.kernel_act_as, list) {
+ if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
+ continue;
+ rc = hp->hook.kernel_act_as(new, blob->secid[hp->lsmid->slot]);
+ if (rc != 0)
+ return rc;
+ }
+ return 0;
}
int security_kernel_create_files_as(struct cred *new, struct inode *inode)
--
2.20.1
^ permalink raw reply related
* [PATCH v5 05/23] LSM: Use lsmblob in security_audit_rule_match
From: Casey Schaufler @ 2019-07-03 21:25 UTC (permalink / raw)
To: casey.schaufler, jmorris, linux-security-module, selinux
Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190703212538.7383-1-casey@schaufler-ca.com>
Change the secid parameter of security_audit_rule_match
to a lsmblob structure pointer. Pass the entry from the
lsmblob structure for the approprite slot to the LSM hook.
Change the users of security_audit_rule_match to use the
lsmblob instead of a u32. In some cases this requires a
temporary conversion using lsmblob_init() that will go
away when other interfaces get converted.
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
include/linux/security.h | 7 ++++---
kernel/auditfilter.c | 7 +++++--
kernel/auditsc.c | 14 ++++++++++----
security/integrity/ima/ima.h | 4 ++--
security/integrity/ima/ima_policy.c | 7 +++++--
security/security.c | 18 +++++++++++++++---
6 files changed, 41 insertions(+), 16 deletions(-)
diff --git a/include/linux/security.h b/include/linux/security.h
index 5bb8b9a6fa84..4f8b478bc3a1 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -1761,7 +1761,8 @@ static inline int security_key_getsecurity(struct key *key, char **_buffer)
#ifdef CONFIG_SECURITY
int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule);
int security_audit_rule_known(struct audit_krule *krule);
-int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule);
+int security_audit_rule_match(struct lsmblob *blob, u32 field, u32 op,
+ void *lsmrule);
void security_audit_rule_free(void *lsmrule);
#else
@@ -1777,8 +1778,8 @@ static inline int security_audit_rule_known(struct audit_krule *krule)
return 0;
}
-static inline int security_audit_rule_match(u32 secid, u32 field, u32 op,
- void *lsmrule)
+static inline int security_audit_rule_match(struct lsmblob *blob, u32 field,
+ u32 op, void *lsmrule)
{
return 0;
}
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index 63f8b3f26fab..8786b95b60bd 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -1324,6 +1324,7 @@ int audit_filter(int msgtype, unsigned int listtype)
struct audit_field *f = &e->rule.fields[i];
pid_t pid;
u32 sid;
+ struct lsmblob blob;
switch (f->type) {
case AUDIT_PID:
@@ -1354,8 +1355,10 @@ int audit_filter(int msgtype, unsigned int listtype)
case AUDIT_SUBJ_CLR:
if (f->lsm_rule) {
security_task_getsecid(current, &sid);
- result = security_audit_rule_match(sid,
- f->type, f->op, f->lsm_rule);
+ lsmblob_init(&blob, sid);
+ result = security_audit_rule_match(
+ &blob, f->type,
+ f->op, f->lsm_rule);
}
break;
case AUDIT_EXE:
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index d1eab1d4a930..18ee5556c086 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -445,6 +445,7 @@ static int audit_filter_rules(struct task_struct *tsk,
const struct cred *cred;
int i, need_sid = 1;
u32 sid;
+ struct lsmblob blob;
unsigned int sessionid;
cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation);
@@ -630,7 +631,9 @@ static int audit_filter_rules(struct task_struct *tsk,
security_task_getsecid(tsk, &sid);
need_sid = 0;
}
- result = security_audit_rule_match(sid, f->type,
+ lsmblob_init(&blob, sid);
+ result = security_audit_rule_match(&blob,
+ f->type,
f->op,
f->lsm_rule);
}
@@ -645,15 +648,17 @@ static int audit_filter_rules(struct task_struct *tsk,
if (f->lsm_rule) {
/* Find files that match */
if (name) {
+ lsmblob_init(&blob, name->osid);
result = security_audit_rule_match(
- name->osid,
+ &blob,
f->type,
f->op,
f->lsm_rule);
} else if (ctx) {
list_for_each_entry(n, &ctx->names_list, list) {
+ lsmblob_init(&blob, n->osid);
if (security_audit_rule_match(
- n->osid,
+ &blob,
f->type,
f->op,
f->lsm_rule)) {
@@ -665,7 +670,8 @@ static int audit_filter_rules(struct task_struct *tsk,
/* Find ipc objects that match */
if (!ctx || ctx->type != AUDIT_IPC)
break;
- if (security_audit_rule_match(ctx->ipc.osid,
+ lsmblob_init(&blob, ctx->ipc.osid);
+ if (security_audit_rule_match(&blob,
f->type, f->op,
f->lsm_rule))
++result;
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index d213e835c498..5a337239d9e4 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -307,8 +307,8 @@ static inline int security_filter_rule_init(u32 field, u32 op, char *rulestr,
return -EINVAL;
}
-static inline int security_filter_rule_match(u32 secid, u32 field, u32 op,
- void *lsmrule)
+static inline int security_filter_rule_match(struct lsmblob *blob, u32 field,
+ u32 op, void *lsmrule)
{
return -EINVAL;
}
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index e0cc323f948f..e7b8ce942950 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -327,6 +327,7 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
for (i = 0; i < MAX_LSM_RULES; i++) {
int rc = 0;
u32 osid;
+ struct lsmblob blob;
int retried = 0;
if (!rule->lsm[i].rule)
@@ -337,7 +338,8 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
case LSM_OBJ_ROLE:
case LSM_OBJ_TYPE:
security_inode_getsecid(inode, &osid);
- rc = security_filter_rule_match(osid,
+ lsmblob_init(&blob, osid);
+ rc = security_filter_rule_match(&blob,
rule->lsm[i].type,
Audit_equal,
rule->lsm[i].rule);
@@ -345,7 +347,8 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
case LSM_SUBJ_USER:
case LSM_SUBJ_ROLE:
case LSM_SUBJ_TYPE:
- rc = security_filter_rule_match(secid,
+ lsmblob_init(&blob, secid);
+ rc = security_filter_rule_match(&blob,
rule->lsm[i].type,
Audit_equal,
rule->lsm[i].rule);
diff --git a/security/security.c b/security/security.c
index 27e2db3d6b04..fa6e425e6f29 100644
--- a/security/security.c
+++ b/security/security.c
@@ -424,7 +424,7 @@ static int lsm_append(const char *new, char **result)
/*
* Current index to use while initializing the lsmblob secid list.
*/
-static int lsm_slot __initdata;
+static int lsm_slot __lsm_ro_after_init;
/**
* security_add_hooks - Add a modules hooks to the hook lists.
@@ -2433,9 +2433,21 @@ void security_audit_rule_free(void *lsmrule)
call_void_hook(audit_rule_free, lsmrule);
}
-int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule)
+int security_audit_rule_match(struct lsmblob *blob, u32 field, u32 op,
+ void *lsmrule)
{
- return call_int_hook(audit_rule_match, 0, secid, field, op, lsmrule);
+ struct security_hook_list *hp;
+ int rc;
+
+ hlist_for_each_entry(hp, &security_hook_heads.audit_rule_match, list) {
+ if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
+ continue;
+ rc = hp->hook.audit_rule_match(blob->secid[hp->lsmid->slot],
+ field, op, lsmrule);
+ if (rc != 0)
+ return rc;
+ }
+ return 0;
}
#endif /* CONFIG_AUDIT */
--
2.20.1
^ permalink raw reply related
* [PATCH v5 03/23] LSM: Infrastructure management of the key blob
From: Casey Schaufler @ 2019-07-03 21:25 UTC (permalink / raw)
To: casey.schaufler, jmorris, linux-security-module, selinux
Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190703212538.7383-1-casey@schaufler-ca.com>
From: Casey Schaufler <cschaufler@schaufler-ca.com>
Move management of the key->security blob out of the
individual security modules and into the security
infrastructure. Instead of allocating the blobs from within
the modules the modules tell the infrastructure how much
space is required, and the space is allocated there.
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <jojn.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
include/linux/lsm_hooks.h | 1 +
security/security.c | 40 ++++++++++++++++++++++++++++++-
security/selinux/hooks.c | 23 +++++-------------
security/selinux/include/objsec.h | 7 ++++++
security/smack/smack.h | 7 ++++++
security/smack/smack_lsm.c | 33 ++++++++++++-------------
6 files changed, 75 insertions(+), 36 deletions(-)
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index b353482ea348..3fe39abccc8f 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -2050,6 +2050,7 @@ struct lsm_blob_sizes {
int lbs_sock;
int lbs_superblock;
int lbs_ipc;
+ int lbs_key;
int lbs_msg_msg;
int lbs_task;
};
diff --git a/security/security.c b/security/security.c
index 2c0834db7976..7cfedb90210a 100644
--- a/security/security.c
+++ b/security/security.c
@@ -172,6 +172,9 @@ static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed)
blob_sizes.lbs_inode = sizeof(struct rcu_head);
lsm_set_blob_size(&needed->lbs_inode, &blob_sizes.lbs_inode);
lsm_set_blob_size(&needed->lbs_ipc, &blob_sizes.lbs_ipc);
+#ifdef CONFIG_KEYS
+ lsm_set_blob_size(&needed->lbs_key, &blob_sizes.lbs_key);
+#endif
lsm_set_blob_size(&needed->lbs_msg_msg, &blob_sizes.lbs_msg_msg);
lsm_set_blob_size(&needed->lbs_sock, &blob_sizes.lbs_sock);
lsm_set_blob_size(&needed->lbs_superblock, &blob_sizes.lbs_superblock);
@@ -307,6 +310,9 @@ static void __init ordered_lsm_init(void)
init_debug("file blob size = %d\n", blob_sizes.lbs_file);
init_debug("inode blob size = %d\n", blob_sizes.lbs_inode);
init_debug("ipc blob size = %d\n", blob_sizes.lbs_ipc);
+#ifdef CONFIG_KEYS
+ init_debug("key blob size = %d\n", blob_sizes.lbs_key);
+#endif /* CONFIG_KEYS */
init_debug("msg_msg blob size = %d\n", blob_sizes.lbs_msg_msg);
init_debug("sock blob size = %d\n", blob_sizes.lbs_sock);
init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock);
@@ -573,6 +579,29 @@ static int lsm_ipc_alloc(struct kern_ipc_perm *kip)
return 0;
}
+#ifdef CONFIG_KEYS
+/**
+ * lsm_key_alloc - allocate a composite key blob
+ * @key: the key that needs a blob
+ *
+ * Allocate the key blob for all the modules
+ *
+ * Returns 0, or -ENOMEM if memory can't be allocated.
+ */
+static int lsm_key_alloc(struct key *key)
+{
+ if (blob_sizes.lbs_key == 0) {
+ key->security = NULL;
+ return 0;
+ }
+
+ key->security = kzalloc(blob_sizes.lbs_key, GFP_KERNEL);
+ if (key->security == NULL)
+ return -ENOMEM;
+ return 0;
+}
+#endif /* CONFIG_KEYS */
+
/**
* lsm_msg_msg_alloc - allocate a composite msg_msg blob
* @mp: the msg_msg that needs a blob
@@ -2339,12 +2368,21 @@ EXPORT_SYMBOL(security_skb_classify_flow);
int security_key_alloc(struct key *key, const struct cred *cred,
unsigned long flags)
{
- return call_int_hook(key_alloc, 0, key, cred, flags);
+ int rc = lsm_key_alloc(key);
+
+ if (unlikely(rc))
+ return rc;
+ rc = call_int_hook(key_alloc, 0, key, cred, flags);
+ if (unlikely(rc))
+ security_key_free(key);
+ return rc;
}
void security_key_free(struct key *key)
{
call_void_hook(key_free, key);
+ kfree(key->security);
+ key->security = NULL;
}
int security_key_permission(key_ref_t key_ref,
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 5d74ed35b728..c83ec2652eda 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -6353,11 +6353,7 @@ static int selinux_key_alloc(struct key *k, const struct cred *cred,
unsigned long flags)
{
const struct task_security_struct *tsec;
- struct key_security_struct *ksec;
-
- ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
- if (!ksec)
- return -ENOMEM;
+ struct key_security_struct *ksec = selinux_key(k);
tsec = selinux_cred(cred);
if (tsec->keycreate_sid)
@@ -6365,18 +6361,9 @@ static int selinux_key_alloc(struct key *k, const struct cred *cred,
else
ksec->sid = tsec->sid;
- k->security = ksec;
return 0;
}
-static void selinux_key_free(struct key *k)
-{
- struct key_security_struct *ksec = k->security;
-
- k->security = NULL;
- kfree(ksec);
-}
-
static int selinux_key_permission(key_ref_t key_ref,
const struct cred *cred,
unsigned perm)
@@ -6394,7 +6381,7 @@ static int selinux_key_permission(key_ref_t key_ref,
sid = cred_sid(cred);
key = key_ref_to_ptr(key_ref);
- ksec = key->security;
+ ksec = selinux_key(key);
return avc_has_perm(&selinux_state,
sid, ksec->sid, SECCLASS_KEY, perm, NULL);
@@ -6402,7 +6389,7 @@ static int selinux_key_permission(key_ref_t key_ref,
static int selinux_key_getsecurity(struct key *key, char **_buffer)
{
- struct key_security_struct *ksec = key->security;
+ struct key_security_struct *ksec = selinux_key(key);
char *context = NULL;
unsigned len;
int rc;
@@ -6627,6 +6614,9 @@ struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
.lbs_file = sizeof(struct file_security_struct),
.lbs_inode = sizeof(struct inode_security_struct),
.lbs_ipc = sizeof(struct ipc_security_struct),
+#ifdef CONFIG_KEYS
+ .lbs_key = sizeof(struct key_security_struct),
+#endif /* CONFIG_KEYS */
.lbs_msg_msg = sizeof(struct msg_security_struct),
.lbs_sock = sizeof(struct sk_security_struct),
.lbs_superblock = sizeof(struct superblock_security_struct),
@@ -6842,7 +6832,6 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
#ifdef CONFIG_KEYS
LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
- LSM_HOOK_INIT(key_free, selinux_key_free),
LSM_HOOK_INIT(key_permission, selinux_key_permission),
LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
#endif
diff --git a/security/selinux/include/objsec.h b/security/selinux/include/objsec.h
index 29f02b8f8f31..3b78aa4ee98f 100644
--- a/security/selinux/include/objsec.h
+++ b/security/selinux/include/objsec.h
@@ -194,6 +194,13 @@ static inline struct superblock_security_struct *selinux_superblock(
return superblock->s_security + selinux_blob_sizes.lbs_superblock;
}
+#ifdef CONFIG_KEYS
+static inline struct key_security_struct *selinux_key(const struct key *key)
+{
+ return key->security + selinux_blob_sizes.lbs_key;
+}
+#endif /* CONFIG_KEYS */
+
static inline struct sk_security_struct *selinux_sock(const struct sock *sock)
{
return sock->sk_security + selinux_blob_sizes.lbs_sock;
diff --git a/security/smack/smack.h b/security/smack/smack.h
index 4ac4bf3310d7..7cc3a3382fee 100644
--- a/security/smack/smack.h
+++ b/security/smack/smack.h
@@ -386,6 +386,13 @@ static inline struct superblock_smack *smack_superblock(
return superblock->s_security + smack_blob_sizes.lbs_superblock;
}
+#ifdef CONFIG_KEYS
+static inline struct smack_known **smack_key(const struct key *key)
+{
+ return key->security + smack_blob_sizes.lbs_key;
+}
+#endif /* CONFIG_KEYS */
+
/*
* Is the directory transmuting?
*/
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index fd69e1bd841b..e9560b078efe 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -4179,23 +4179,13 @@ static void smack_inet_csk_clone(struct sock *sk,
static int smack_key_alloc(struct key *key, const struct cred *cred,
unsigned long flags)
{
+ struct smack_known **blob = smack_key(key);
struct smack_known *skp = smk_of_task(smack_cred(cred));
- key->security = skp;
+ *blob = skp;
return 0;
}
-/**
- * smack_key_free - Clear the key security blob
- * @key: the object
- *
- * Clear the blob pointer
- */
-static void smack_key_free(struct key *key)
-{
- key->security = NULL;
-}
-
/**
* smack_key_permission - Smack access on a key
* @key_ref: gets to the object
@@ -4208,6 +4198,8 @@ static void smack_key_free(struct key *key)
static int smack_key_permission(key_ref_t key_ref,
const struct cred *cred, unsigned perm)
{
+ struct smack_known **blob;
+ struct smack_known *skp;
struct key *keyp;
struct smk_audit_info ad;
struct smack_known *tkp = smk_of_task(smack_cred(cred));
@@ -4227,7 +4219,9 @@ static int smack_key_permission(key_ref_t key_ref,
* If the key hasn't been initialized give it access so that
* it may do so.
*/
- if (keyp->security == NULL)
+ blob = smack_key(keyp);
+ skp = *blob;
+ if (skp == NULL)
return 0;
/*
* This should not occur
@@ -4247,8 +4241,8 @@ static int smack_key_permission(key_ref_t key_ref,
request |= MAY_READ;
if (perm & (KEY_NEED_WRITE | KEY_NEED_LINK | KEY_NEED_SETATTR))
request |= MAY_WRITE;
- rc = smk_access(tkp, keyp->security, request, &ad);
- rc = smk_bu_note("key access", tkp, keyp->security, request, rc);
+ rc = smk_access(tkp, skp, request, &ad);
+ rc = smk_bu_note("key access", tkp, skp, request, rc);
return rc;
}
@@ -4263,11 +4257,12 @@ static int smack_key_permission(key_ref_t key_ref,
*/
static int smack_key_getsecurity(struct key *key, char **_buffer)
{
- struct smack_known *skp = key->security;
+ struct smack_known **blob = smack_key(key);
+ struct smack_known *skp = *blob;
size_t length;
char *copy;
- if (key->security == NULL) {
+ if (skp == NULL) {
*_buffer = NULL;
return 0;
}
@@ -4550,6 +4545,9 @@ struct lsm_blob_sizes smack_blob_sizes __lsm_ro_after_init = {
.lbs_file = sizeof(struct smack_known *),
.lbs_inode = sizeof(struct inode_smack),
.lbs_ipc = sizeof(struct smack_known *),
+#ifdef CONFIG_KEYS
+ .lbs_key = sizeof(struct smack_known *),
+#endif /* CONFIG_KEYS */
.lbs_msg_msg = sizeof(struct smack_known *),
.lbs_sock = sizeof(struct socket_smack),
.lbs_superblock = sizeof(struct superblock_smack),
@@ -4671,7 +4669,6 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
/* key management security hooks */
#ifdef CONFIG_KEYS
LSM_HOOK_INIT(key_alloc, smack_key_alloc),
- LSM_HOOK_INIT(key_free, smack_key_free),
LSM_HOOK_INIT(key_permission, smack_key_permission),
LSM_HOOK_INIT(key_getsecurity, smack_key_getsecurity),
#endif /* CONFIG_KEYS */
--
2.20.1
^ permalink raw reply related
* [PATCH v5 04/23] LSM: Create and manage the lsmblob data structure.
From: Casey Schaufler @ 2019-07-03 21:25 UTC (permalink / raw)
To: casey.schaufler, jmorris, linux-security-module, selinux
Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190703212538.7383-1-casey@schaufler-ca.com>
When more than one security module is exporting data to
audit and networking sub-systems a single 32 bit integer
is no longer sufficient to represent the data. Add a
structure to be used instead.
The lsmblob structure is currently an array of
u32 "secids". There is an entry for each of the
security modules built into the system that would
use secids if active. The system assigns the module
a "slot" when it registers hooks. If modules are
compiled in but not registered there will be unused
slots.
A new lsm_id structure, which contains the name
of the LSM and its slot number, is created. There
is an instance for each LSM, which assigns the name
and passes it to the infrastructure to set the slot.
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
include/linux/lsm_hooks.h | 12 +++++--
include/linux/security.h | 66 ++++++++++++++++++++++++++++++++++++++
security/apparmor/lsm.c | 7 +++-
security/commoncap.c | 7 +++-
security/loadpin/loadpin.c | 8 ++++-
security/safesetid/lsm.c | 8 ++++-
security/security.c | 31 ++++++++++++++----
security/selinux/hooks.c | 8 ++++-
security/smack/smack_lsm.c | 7 +++-
security/tomoyo/tomoyo.c | 8 ++++-
security/yama/yama_lsm.c | 7 +++-
11 files changed, 152 insertions(+), 17 deletions(-)
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index 3fe39abccc8f..fe1fb7a69ee5 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -2029,6 +2029,14 @@ struct security_hook_heads {
#endif /* CONFIG_BPF_SYSCALL */
} __randomize_layout;
+/*
+ * Information that identifies a security module.
+ */
+struct lsm_id {
+ const char *lsm; /* Name of the LSM */
+ int slot; /* Slot in lsmblob if one is allocated */
+};
+
/*
* Security module hook list structure.
* For use with generic list macros for common operations.
@@ -2037,7 +2045,7 @@ struct security_hook_list {
struct hlist_node list;
struct hlist_head *head;
union security_list_options hook;
- char *lsm;
+ struct lsm_id *lsmid;
} __randomize_layout;
/*
@@ -2068,7 +2076,7 @@ extern struct security_hook_heads security_hook_heads;
extern char *lsm_names;
extern void security_add_hooks(struct security_hook_list *hooks, int count,
- char *lsm);
+ struct lsm_id *lsmid);
#define LSM_FLAG_LEGACY_MAJOR BIT(0)
#define LSM_FLAG_EXCLUSIVE BIT(1)
diff --git a/include/linux/security.h b/include/linux/security.h
index 49f2685324b0..5bb8b9a6fa84 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -76,6 +76,72 @@ enum lsm_event {
LSM_POLICY_CHANGE,
};
+/*
+ * Data exported by the security modules
+ *
+ * Any LSM that provides secid or secctx based hooks must be included.
+ */
+#define LSMBLOB_ENTRIES ( \
+ (IS_ENABLED(CONFIG_SECURITY_SELINUX) ? 1 : 0) + \
+ (IS_ENABLED(CONFIG_SECURITY_SMACK) ? 1 : 0) + \
+ (IS_ENABLED(CONFIG_SECURITY_APPARMOR) ? 1 : 0))
+
+struct lsmblob {
+ u32 secid[LSMBLOB_ENTRIES];
+};
+
+#define LSMBLOB_INVALID -1 /* Not a valid LSM slot number */
+#define LSMBLOB_NEEDED -2 /* Slot requested on initialization */
+#define LSMBLOB_NOT_NEEDED -3 /* Slot not requested */
+
+/**
+ * lsmblob_init - initialize an lsmblob structure.
+ * @blob: Pointer to the data to initialize
+ * @secid: The initial secid value
+ *
+ * Set all secid for all modules to the specified value.
+ */
+static inline void lsmblob_init(struct lsmblob *blob, u32 secid)
+{
+ int i;
+
+ for (i = 0; i < LSMBLOB_ENTRIES; i++)
+ blob->secid[i] = secid;
+}
+
+/**
+ * lsmblob_is_set - report if there is an value in the lsmblob
+ * @blob: Pointer to the exported LSM data
+ *
+ * Returns true if there is a secid set, false otherwise
+ */
+static inline bool lsmblob_is_set(struct lsmblob *blob)
+{
+ int i;
+
+ for (i = 0; i < LSMBLOB_ENTRIES; i++)
+ if (blob->secid[i] != 0)
+ return true;
+ return false;
+}
+
+/**
+ * lsmblob_equal - report if the two lsmblob's are equal
+ * @bloba: Pointer to one LSM data
+ * @blobb: Pointer to the other LSM data
+ *
+ * Returns true if all entries in the two are equal, false otherwise
+ */
+static inline bool lsmblob_equal(struct lsmblob *bloba, struct lsmblob *blobb)
+{
+ int i;
+
+ for (i = 0; i < LSMBLOB_ENTRIES; i++)
+ if (bloba->secid[i] != blobb->secid[i])
+ return false;
+ return true;
+}
+
/* These functions are in security/commoncap.c */
extern int cap_capable(const struct cred *cred, struct user_namespace *ns,
int cap, unsigned int opts);
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
index 2716e7731279..ec2e39aa9a84 100644
--- a/security/apparmor/lsm.c
+++ b/security/apparmor/lsm.c
@@ -1138,6 +1138,11 @@ struct lsm_blob_sizes apparmor_blob_sizes __lsm_ro_after_init = {
.lbs_sock = sizeof(struct aa_sk_ctx),
};
+static struct lsm_id apparmor_lsmid __lsm_ro_after_init = {
+ .lsm = "apparmor",
+ .slot = LSMBLOB_NEEDED
+};
+
static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
@@ -1679,7 +1684,7 @@ static int __init apparmor_init(void)
goto buffers_out;
}
security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks),
- "apparmor");
+ &apparmor_lsmid);
/* Report that AppArmor successfully initialized */
apparmor_initialized = 1;
diff --git a/security/commoncap.c b/security/commoncap.c
index c477fb673701..872542df603b 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -1344,6 +1344,11 @@ int cap_mmap_file(struct file *file, unsigned long reqprot,
#ifdef CONFIG_SECURITY
+static struct lsm_id capability_lsmid __lsm_ro_after_init = {
+ .lsm = "capability",
+ .slot = LSMBLOB_NOT_NEEDED
+};
+
struct security_hook_list capability_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(capable, cap_capable),
LSM_HOOK_INIT(settime, cap_settime),
@@ -1368,7 +1373,7 @@ struct security_hook_list capability_hooks[] __lsm_ro_after_init = {
static int __init capability_init(void)
{
security_add_hooks(capability_hooks, ARRAY_SIZE(capability_hooks),
- "capability");
+ &capability_lsmid);
return 0;
}
diff --git a/security/loadpin/loadpin.c b/security/loadpin/loadpin.c
index 055fb0a64169..7b23fdf24e27 100644
--- a/security/loadpin/loadpin.c
+++ b/security/loadpin/loadpin.c
@@ -181,6 +181,11 @@ static int loadpin_load_data(enum kernel_load_data_id id)
return loadpin_read_file(NULL, (enum kernel_read_file_id) id);
}
+static struct lsm_id loadpin_lsmid __lsm_ro_after_init = {
+ .lsm = "loadpin",
+ .slot = LSMBLOB_NOT_NEEDED
+};
+
static struct security_hook_list loadpin_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(sb_free_security, loadpin_sb_free_security),
LSM_HOOK_INIT(kernel_read_file, loadpin_read_file),
@@ -191,7 +196,8 @@ static int __init loadpin_init(void)
{
pr_info("ready to pin (currently %senforcing)\n",
enforce ? "" : "not ");
- security_add_hooks(loadpin_hooks, ARRAY_SIZE(loadpin_hooks), "loadpin");
+ security_add_hooks(loadpin_hooks, ARRAY_SIZE(loadpin_hooks),
+ &loadpin_lsmid);
return 0;
}
diff --git a/security/safesetid/lsm.c b/security/safesetid/lsm.c
index cecd38e2ac80..4a96cd8c0d15 100644
--- a/security/safesetid/lsm.c
+++ b/security/safesetid/lsm.c
@@ -255,6 +255,11 @@ void flush_safesetid_whitelist_entries(void)
}
}
+static struct lsm_id safesetid_lsmid __lsm_ro_after_init = {
+ .lsm = "safesetid",
+ .slot = LSMBLOB_NOT_NEEDED
+};
+
static struct security_hook_list safesetid_security_hooks[] = {
LSM_HOOK_INIT(task_fix_setuid, safesetid_task_fix_setuid),
LSM_HOOK_INIT(capable, safesetid_security_capable)
@@ -263,7 +268,8 @@ static struct security_hook_list safesetid_security_hooks[] = {
static int __init safesetid_security_init(void)
{
security_add_hooks(safesetid_security_hooks,
- ARRAY_SIZE(safesetid_security_hooks), "safesetid");
+ ARRAY_SIZE(safesetid_security_hooks),
+ &safesetid_lsmid);
/* Report that SafeSetID successfully initialized */
safesetid_initialized = 1;
diff --git a/security/security.c b/security/security.c
index 7cfedb90210a..27e2db3d6b04 100644
--- a/security/security.c
+++ b/security/security.c
@@ -317,6 +317,7 @@ static void __init ordered_lsm_init(void)
init_debug("sock blob size = %d\n", blob_sizes.lbs_sock);
init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock);
init_debug("task blob size = %d\n", blob_sizes.lbs_task);
+ init_debug("lsmblob size = %lu\n", sizeof(struct lsmblob));
/*
* Create any kmem_caches needed for blobs
@@ -399,7 +400,7 @@ static bool match_last_lsm(const char *list, const char *lsm)
return !strcmp(last, lsm);
}
-static int lsm_append(char *new, char **result)
+static int lsm_append(const char *new, char **result)
{
char *cp;
@@ -420,24 +421,40 @@ static int lsm_append(char *new, char **result)
return 0;
}
+/*
+ * Current index to use while initializing the lsmblob secid list.
+ */
+static int lsm_slot __initdata;
+
/**
* security_add_hooks - Add a modules hooks to the hook lists.
* @hooks: the hooks to add
* @count: the number of hooks to add
- * @lsm: the name of the security module
+ * @lsmid: the identification information for the security module
*
* Each LSM has to register its hooks with the infrastructure.
+ * If the LSM is using hooks that export secids allocate a slot
+ * for it in the lsmblob.
*/
void __init security_add_hooks(struct security_hook_list *hooks, int count,
- char *lsm)
+ struct lsm_id *lsmid)
{
int i;
+ if (lsmid->slot == LSMBLOB_NEEDED) {
+ if (lsm_slot >= LSMBLOB_ENTRIES)
+ panic("%s Too many LSMs registered.\n", __func__);
+ lsmid->slot = lsm_slot++;
+ init_debug("%s assigned lsmblob slot %d\n", lsmid->lsm,
+ lsmid->slot);
+ }
+
for (i = 0; i < count; i++) {
- hooks[i].lsm = lsm;
+ hooks[i].lsmid = lsmid;
hlist_add_tail_rcu(&hooks[i].list, hooks[i].head);
}
- if (lsm_append(lsm, &lsm_names) < 0)
+
+ if (lsm_append(lsmid->lsm, &lsm_names) < 0)
panic("%s - Cannot get early memory.\n", __func__);
}
@@ -1917,7 +1934,7 @@ int security_getprocattr(struct task_struct *p, const char *lsm, char *name,
struct security_hook_list *hp;
hlist_for_each_entry(hp, &security_hook_heads.getprocattr, list) {
- if (lsm != NULL && strcmp(lsm, hp->lsm))
+ if (lsm != NULL && strcmp(lsm, hp->lsmid->lsm))
continue;
return hp->hook.getprocattr(p, name, value);
}
@@ -1930,7 +1947,7 @@ int security_setprocattr(const char *lsm, const char *name, void *value,
struct security_hook_list *hp;
hlist_for_each_entry(hp, &security_hook_heads.setprocattr, list) {
- if (lsm != NULL && strcmp(lsm, hp->lsm))
+ if (lsm != NULL && strcmp(lsm, hp->lsmid->lsm))
continue;
return hp->hook.setprocattr(name, value, size);
}
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index c83ec2652eda..74c491980ed2 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -6622,6 +6622,11 @@ struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
.lbs_superblock = sizeof(struct superblock_security_struct),
};
+static struct lsm_id selinux_lsmid __lsm_ro_after_init = {
+ .lsm = "selinux",
+ .slot = LSMBLOB_NEEDED
+};
+
static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
@@ -6877,7 +6882,8 @@ static __init int selinux_init(void)
hashtab_cache_init();
- security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
+ security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks),
+ &selinux_lsmid);
if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
panic("SELinux: Unable to register AVC netcache callback\n");
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index e9560b078efe..7a0ead4da479 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -4553,6 +4553,11 @@ struct lsm_blob_sizes smack_blob_sizes __lsm_ro_after_init = {
.lbs_superblock = sizeof(struct superblock_smack),
};
+static struct lsm_id smack_lsmid __lsm_ro_after_init = {
+ .lsm = "smack",
+ .slot = LSMBLOB_NEEDED
+};
+
static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(ptrace_access_check, smack_ptrace_access_check),
LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme),
@@ -4743,7 +4748,7 @@ static __init int smack_init(void)
/*
* Register with LSM
*/
- security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), "smack");
+ security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), &smack_lsmid);
smack_enabled = 1;
pr_info("Smack: Initializing.\n");
diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c
index 716c92ec941a..f1968e80f06d 100644
--- a/security/tomoyo/tomoyo.c
+++ b/security/tomoyo/tomoyo.c
@@ -529,6 +529,11 @@ static void tomoyo_task_free(struct task_struct *task)
}
}
+static struct lsm_id tomoyo_lsmid __lsm_ro_after_init = {
+ .lsm = "tomoyo",
+ .slot = LSMBLOB_NOT_NEEDED
+};
+
/*
* tomoyo_security_ops is a "struct security_operations" which is used for
* registering TOMOYO.
@@ -581,7 +586,8 @@ static int __init tomoyo_init(void)
struct tomoyo_task *s = tomoyo_task(current);
/* register ourselves with the security framework */
- security_add_hooks(tomoyo_hooks, ARRAY_SIZE(tomoyo_hooks), "tomoyo");
+ security_add_hooks(tomoyo_hooks, ARRAY_SIZE(tomoyo_hooks),
+ &tomoyo_lsmid);
pr_info("TOMOYO Linux initialized\n");
s->domain_info = &tomoyo_kernel_domain;
atomic_inc(&tomoyo_kernel_domain.users);
diff --git a/security/yama/yama_lsm.c b/security/yama/yama_lsm.c
index efac68556b45..0529ecc86954 100644
--- a/security/yama/yama_lsm.c
+++ b/security/yama/yama_lsm.c
@@ -425,6 +425,11 @@ static int yama_ptrace_traceme(struct task_struct *parent)
return rc;
}
+static struct lsm_id yama_lsmid __lsm_ro_after_init = {
+ .lsm = "yama",
+ .slot = LSMBLOB_NOT_NEEDED
+};
+
static struct security_hook_list yama_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(ptrace_access_check, yama_ptrace_access_check),
LSM_HOOK_INIT(ptrace_traceme, yama_ptrace_traceme),
@@ -482,7 +487,7 @@ static inline void yama_init_sysctl(void) { }
static int __init yama_init(void)
{
pr_info("Yama: becoming mindful.\n");
- security_add_hooks(yama_hooks, ARRAY_SIZE(yama_hooks), "yama");
+ security_add_hooks(yama_hooks, ARRAY_SIZE(yama_hooks), &yama_lsmid);
yama_init_sysctl();
return 0;
}
--
2.20.1
^ permalink raw reply related
* [PATCH v5 00/23] LSM: Module stacking for AppArmor
From: Casey Schaufler @ 2019-07-03 21:25 UTC (permalink / raw)
To: casey.schaufler, jmorris, linux-security-module, selinux
Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
This patchset provides the changes required for
the AppArmor security module to stack safely with any other.
v5: Incorporate feedback from v4
- Initialize the lsmcontext in security_secid_to_secctx()
- Clear the lsmcontext in all security_release_secctx() cases
- Don't use the "display" on strictly internal context
interfaces.
- The SELinux binder hooks check for cases where the context
"display" isn't compatible with SELinux.
v4: Incorporate feedback from v3
- Mark new lsm_<blob>_alloc functions static
- Replace the lsm and slot fields of the security_hook_list
with a pointer to a LSM allocated lsm_id structure. The
LSM identifies if it needs a slot explicitly. Use the
lsm_id rather than make security_add_hooks return the
slot value.
- Validate slot values used in security.c
- Reworked the "display" process attribute handling so that
it works right and doesn't use goofy list processing.
- fix display value check in dentry_init_security
- Replace audit_log of secids with '?' instead of deleting
the audit log
v3: Incorporate feedback from v2
- Make lsmblob parameter and variable names more
meaningful, changing "le" and "l" to "blob".
- Improve consistency of constant naming.
- Do more sanity checking during LSM initialization.
- Be a bit clearer about what is temporary scaffolding.
- Rather than clutter security_getpeersec_dgram with
otherwise unnecessary checks remove the apparmor
stub, which does nothing useful.
Patches 0001-0003 complete the process of moving management
of security blobs that might be shared from the individual
modules to the infrastructure.
Patches 0004-0014 replace system use of a "secid" with
a structure "lsmblob" containing information from the
security modules to be held and reused later. At this
point lsmblob contains an array of u32 secids, one "slot"
for each of the security modules compiled into the
kernel that used secids. A "slot" is allocated when
a security module requests one.
The infrastructure is changed to use the slot number
to pass the correct secid to or from the security module
hooks.
It is important that the lsmblob be a fixed size entity
that does not have to be allocated. Several of the places
where it is used would have performance and/or locking
issues with dynamic allocation.
Patch 0015 provides a mechanism for a process to
identify which security module's hooks should be used
when displaying or converting a security context string.
A new interface /proc/.../attr/display contains the name
of the security module to show. Reading from this file
will present the name of the module, while writing to
it will set the value. Only names of active security
modules are accepted. Internally, the name is translated
to the appropriate "slot" number for the module which
is then stored in the task security blob.
Patch 0016 Starts the process of changing how a security
context is represented. Since it is possible for a
security context to have been generated by more than one
security module it is now necessary to note which module
created a security context so that the correct "release"
hook can be called. There are several places where the
module that created a security context cannot be inferred.
This is achieved by introducing a "lsmcontext" structure
which contains the context string, its length and the
"slot" number of the security module that created it.
The security_release_secctx() interface is changed,
replacing the (string,len) pointer pair with a lsmcontext
pointer.
Patches 0017-0020 convert the security interfaces from
(string,len) pointer pairs to a lsmcontext pointer.
The slot number identifying the creating module is
added by the infrastructure. Where the security context
is stored for extended periods the data type is changed.
The Netlabel code is converted to save lsmblob structures
instead of secids in Patch 0021.
Finally, with all interference on the AppArmor hooks
removed, Patch 0022 removes the exclusive bit from
AppArmor. An unnecessary stub hook was also removed.
Patch 0023 adds checks to the SELinux binder hooks
which verify that if either "display" used is SELinux
both are.
The Ubuntu project is using an earlier version of
this patchset in their distribution to enable stacking
for containers.
Performance measurements to date have the change
within the "noise". Better benchmarks are in the
works.
https://github.com/cschaufler/lsm-stacking.git#stack-5.2-v5-apparmor
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
drivers/android/binder.c | 24 +-
fs/kernfs/dir.c | 5 +-
fs/kernfs/inode.c | 35 +--
fs/kernfs/kernfs-internal.h | 3 +-
fs/nfs/nfs4proc.c | 22 +-
fs/nfsd/nfs4xdr.c | 20 +-
fs/proc/base.c | 1 +
include/linux/cred.h | 3 +-
include/linux/lsm_hooks.h | 28 +-
include/linux/security.h | 169 +++++++++---
include/net/af_unix.h | 2 +-
include/net/netlabel.h | 8 +-
include/net/scm.h | 14 +-
kernel/audit.c | 34 +--
kernel/audit.h | 5 +-
kernel/auditfilter.c | 9 +-
kernel/auditsc.c | 83 +++---
kernel/cred.c | 12 +-
net/ipv4/cipso_ipv4.c | 6 +-
net/ipv4/ip_sockglue.c | 12 +-
net/netfilter/nf_conntrack_netlink.c | 20 +-
net/netfilter/nf_conntrack_standalone.c | 11 +-
net/netfilter/nfnetlink_queue.c | 26 +-
net/netfilter/nft_meta.c | 13 +-
net/netfilter/xt_SECMARK.c | 5 +-
net/netlabel/netlabel_kapi.c | 6 +-
net/netlabel/netlabel_unlabeled.c | 95 ++++---
net/netlabel/netlabel_unlabeled.h | 2 +-
net/netlabel/netlabel_user.c | 13 +-
net/netlabel/netlabel_user.h | 6 +-
net/unix/af_unix.c | 6 +-
security/apparmor/include/net.h | 6 +-
security/apparmor/lsm.c | 65 ++---
security/commoncap.c | 7 +-
security/integrity/ima/ima.h | 14 +-
security/integrity/ima/ima_api.c | 9 +-
security/integrity/ima/ima_appraise.c | 6 +-
security/integrity/ima/ima_main.c | 36 +--
security/integrity/ima/ima_policy.c | 19 +-
security/loadpin/loadpin.c | 8 +-
security/safesetid/lsm.c | 8 +-
security/security.c | 445 ++++++++++++++++++++++++++++----
security/selinux/hooks.c | 201 ++++++++-------
security/selinux/include/objsec.h | 18 ++
security/selinux/include/security.h | 1 +
security/selinux/netlabel.c | 25 +-
security/selinux/ss/services.c | 7 +-
security/smack/smack.h | 19 ++
security/smack/smack_lsm.c | 156 ++++++-----
security/smack/smack_netfilter.c | 8 +-
security/smack/smackfs.c | 10 +-
security/tomoyo/tomoyo.c | 8 +-
security/yama/yama_lsm.c | 7 +-
53 files changed, 1167 insertions(+), 614 deletions(-)
^ permalink raw reply
* [PATCH v5 01/23] LSM: Infrastructure management of the superblock
From: Casey Schaufler @ 2019-07-03 21:25 UTC (permalink / raw)
To: casey.schaufler, jmorris, linux-security-module, selinux
Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190703212538.7383-1-casey@schaufler-ca.com>
Move management of the superblock->sb_security blob out
of the individual security modules and into the security
infrastructure. Instead of allocating the blobs from within
the modules the modules tell the infrastructure how much
space is required, and the space is allocated there.
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
include/linux/lsm_hooks.h | 1 +
security/security.c | 46 ++++++++++++++++++++----
security/selinux/hooks.c | 58 ++++++++++++-------------------
security/selinux/include/objsec.h | 6 ++++
security/selinux/ss/services.c | 3 +-
security/smack/smack.h | 6 ++++
security/smack/smack_lsm.c | 35 +++++--------------
7 files changed, 85 insertions(+), 70 deletions(-)
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index a240a3fc5fc4..f9222a04968d 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -2047,6 +2047,7 @@ struct lsm_blob_sizes {
int lbs_cred;
int lbs_file;
int lbs_inode;
+ int lbs_superblock;
int lbs_ipc;
int lbs_msg_msg;
int lbs_task;
diff --git a/security/security.c b/security/security.c
index 23cbb1a295a3..86198e303203 100644
--- a/security/security.c
+++ b/security/security.c
@@ -172,6 +172,7 @@ static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed)
lsm_set_blob_size(&needed->lbs_inode, &blob_sizes.lbs_inode);
lsm_set_blob_size(&needed->lbs_ipc, &blob_sizes.lbs_ipc);
lsm_set_blob_size(&needed->lbs_msg_msg, &blob_sizes.lbs_msg_msg);
+ lsm_set_blob_size(&needed->lbs_superblock, &blob_sizes.lbs_superblock);
lsm_set_blob_size(&needed->lbs_task, &blob_sizes.lbs_task);
}
@@ -300,12 +301,13 @@ static void __init ordered_lsm_init(void)
for (lsm = ordered_lsms; *lsm; lsm++)
prepare_lsm(*lsm);
- init_debug("cred blob size = %d\n", blob_sizes.lbs_cred);
- init_debug("file blob size = %d\n", blob_sizes.lbs_file);
- init_debug("inode blob size = %d\n", blob_sizes.lbs_inode);
- init_debug("ipc blob size = %d\n", blob_sizes.lbs_ipc);
- init_debug("msg_msg blob size = %d\n", blob_sizes.lbs_msg_msg);
- init_debug("task blob size = %d\n", blob_sizes.lbs_task);
+ init_debug("cred blob size = %d\n", blob_sizes.lbs_cred);
+ init_debug("file blob size = %d\n", blob_sizes.lbs_file);
+ init_debug("inode blob size = %d\n", blob_sizes.lbs_inode);
+ init_debug("ipc blob size = %d\n", blob_sizes.lbs_ipc);
+ init_debug("msg_msg blob size = %d\n", blob_sizes.lbs_msg_msg);
+ init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock);
+ init_debug("task blob size = %d\n", blob_sizes.lbs_task);
/*
* Create any kmem_caches needed for blobs
@@ -603,6 +605,27 @@ static void __init lsm_early_task(struct task_struct *task)
panic("%s: Early task alloc failed.\n", __func__);
}
+/**
+ * lsm_superblock_alloc - allocate a composite superblock blob
+ * @sb: the superblock that needs a blob
+ *
+ * Allocate the superblock blob for all the modules
+ *
+ * Returns 0, or -ENOMEM if memory can't be allocated.
+ */
+static int lsm_superblock_alloc(struct super_block *sb)
+{
+ if (blob_sizes.lbs_superblock == 0) {
+ sb->s_security = NULL;
+ return 0;
+ }
+
+ sb->s_security = kzalloc(blob_sizes.lbs_superblock, GFP_KERNEL);
+ if (sb->s_security == NULL)
+ return -ENOMEM;
+ return 0;
+}
+
/*
* Hook list operation macros.
*
@@ -776,12 +799,21 @@ int security_fs_context_parse_param(struct fs_context *fc, struct fs_parameter *
int security_sb_alloc(struct super_block *sb)
{
- return call_int_hook(sb_alloc_security, 0, sb);
+ int rc = lsm_superblock_alloc(sb);
+
+ if (unlikely(rc))
+ return rc;
+ rc = call_int_hook(sb_alloc_security, 0, sb);
+ if (unlikely(rc))
+ security_sb_free(sb);
+ return rc;
}
void security_sb_free(struct super_block *sb)
{
call_void_hook(sb_free_security, sb);
+ kfree(sb->s_security);
+ sb->s_security = NULL;
}
void security_free_mnt_opts(void **mnt_opts)
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 1d0b37af2444..7478d8eda00a 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -335,7 +335,7 @@ static void inode_free_security(struct inode *inode)
if (!isec)
return;
- sbsec = inode->i_sb->s_security;
+ sbsec = selinux_superblock(inode->i_sb);
/*
* As not all inode security structures are in a list, we check for
* empty list outside of the lock to make sure that we won't waste
@@ -366,11 +366,7 @@ static int file_alloc_security(struct file *file)
static int superblock_alloc_security(struct super_block *sb)
{
- struct superblock_security_struct *sbsec;
-
- sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
- if (!sbsec)
- return -ENOMEM;
+ struct superblock_security_struct *sbsec = selinux_superblock(sb);
mutex_init(&sbsec->lock);
INIT_LIST_HEAD(&sbsec->isec_head);
@@ -379,18 +375,10 @@ static int superblock_alloc_security(struct super_block *sb)
sbsec->sid = SECINITSID_UNLABELED;
sbsec->def_sid = SECINITSID_FILE;
sbsec->mntpoint_sid = SECINITSID_UNLABELED;
- sb->s_security = sbsec;
return 0;
}
-static void superblock_free_security(struct super_block *sb)
-{
- struct superblock_security_struct *sbsec = sb->s_security;
- sb->s_security = NULL;
- kfree(sbsec);
-}
-
struct selinux_mnt_opts {
const char *fscontext, *context, *rootcontext, *defcontext;
};
@@ -507,7 +495,7 @@ static int selinux_is_genfs_special_handling(struct super_block *sb)
static int selinux_is_sblabel_mnt(struct super_block *sb)
{
- struct superblock_security_struct *sbsec = sb->s_security;
+ struct superblock_security_struct *sbsec = selinux_superblock(sb);
/*
* IMPORTANT: Double-check logic in this function when adding a new
@@ -535,7 +523,7 @@ static int selinux_is_sblabel_mnt(struct super_block *sb)
static int sb_finish_set_opts(struct super_block *sb)
{
- struct superblock_security_struct *sbsec = sb->s_security;
+ struct superblock_security_struct *sbsec = selinux_superblock(sb);
struct dentry *root = sb->s_root;
struct inode *root_inode = d_backing_inode(root);
int rc = 0;
@@ -648,7 +636,7 @@ static int selinux_set_mnt_opts(struct super_block *sb,
unsigned long *set_kern_flags)
{
const struct cred *cred = current_cred();
- struct superblock_security_struct *sbsec = sb->s_security;
+ struct superblock_security_struct *sbsec = selinux_superblock(sb);
struct dentry *root = sbsec->sb->s_root;
struct selinux_mnt_opts *opts = mnt_opts;
struct inode_security_struct *root_isec;
@@ -881,8 +869,8 @@ static int selinux_set_mnt_opts(struct super_block *sb,
static int selinux_cmp_sb_context(const struct super_block *oldsb,
const struct super_block *newsb)
{
- struct superblock_security_struct *old = oldsb->s_security;
- struct superblock_security_struct *new = newsb->s_security;
+ struct superblock_security_struct *old = selinux_superblock(oldsb);
+ struct superblock_security_struct *new = selinux_superblock(newsb);
char oldflags = old->flags & SE_MNTMASK;
char newflags = new->flags & SE_MNTMASK;
@@ -914,8 +902,9 @@ static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
unsigned long *set_kern_flags)
{
int rc = 0;
- const struct superblock_security_struct *oldsbsec = oldsb->s_security;
- struct superblock_security_struct *newsbsec = newsb->s_security;
+ const struct superblock_security_struct *oldsbsec =
+ selinux_superblock(oldsb);
+ struct superblock_security_struct *newsbsec = selinux_superblock(newsb);
int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
int set_context = (oldsbsec->flags & CONTEXT_MNT);
@@ -1085,7 +1074,7 @@ static int show_sid(struct seq_file *m, u32 sid)
static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
{
- struct superblock_security_struct *sbsec = sb->s_security;
+ struct superblock_security_struct *sbsec = selinux_superblock(sb);
int rc;
if (!(sbsec->flags & SE_SBINITIALIZED))
@@ -1377,7 +1366,7 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent
if (isec->sclass == SECCLASS_FILE)
isec->sclass = inode_mode_to_security_class(inode->i_mode);
- sbsec = inode->i_sb->s_security;
+ sbsec = selinux_superblock(inode->i_sb);
if (!(sbsec->flags & SE_SBINITIALIZED)) {
/* Defer initialization until selinux_complete_init,
after the initial policy is loaded and the security
@@ -1767,7 +1756,8 @@ selinux_determine_inode_label(const struct task_security_struct *tsec,
const struct qstr *name, u16 tclass,
u32 *_new_isid)
{
- const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
+ const struct superblock_security_struct *sbsec =
+ selinux_superblock(dir->i_sb);
if ((sbsec->flags & SE_SBINITIALIZED) &&
(sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
@@ -1798,7 +1788,7 @@ static int may_create(struct inode *dir,
int rc;
dsec = inode_security(dir);
- sbsec = dir->i_sb->s_security;
+ sbsec = selinux_superblock(dir->i_sb);
sid = tsec->sid;
@@ -1947,7 +1937,7 @@ static int superblock_has_perm(const struct cred *cred,
struct superblock_security_struct *sbsec;
u32 sid = cred_sid(cred);
- sbsec = sb->s_security;
+ sbsec = selinux_superblock(sb);
return avc_has_perm(&selinux_state,
sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
}
@@ -2578,11 +2568,6 @@ static int selinux_sb_alloc_security(struct super_block *sb)
return superblock_alloc_security(sb);
}
-static void selinux_sb_free_security(struct super_block *sb)
-{
- superblock_free_security(sb);
-}
-
static inline int opt_len(const char *s)
{
bool open_quote = false;
@@ -2653,7 +2638,7 @@ static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
{
struct selinux_mnt_opts *opts = mnt_opts;
- struct superblock_security_struct *sbsec = sb->s_security;
+ struct superblock_security_struct *sbsec = selinux_superblock(sb);
u32 sid;
int rc;
@@ -2877,7 +2862,7 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
int rc;
char *context;
- sbsec = dir->i_sb->s_security;
+ sbsec = selinux_superblock(dir->i_sb);
newsid = tsec->create_sid;
@@ -3115,7 +3100,7 @@ static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
}
- sbsec = inode->i_sb->s_security;
+ sbsec = selinux_superblock(inode->i_sb);
if (!(sbsec->flags & SBLABEL_MNT))
return -EOPNOTSUPP;
@@ -3296,13 +3281,14 @@ static int selinux_inode_setsecurity(struct inode *inode, const char *name,
const void *value, size_t size, int flags)
{
struct inode_security_struct *isec = inode_security_novalidate(inode);
- struct superblock_security_struct *sbsec = inode->i_sb->s_security;
+ struct superblock_security_struct *sbsec;
u32 newsid;
int rc;
if (strcmp(name, XATTR_SELINUX_SUFFIX))
return -EOPNOTSUPP;
+ sbsec = selinux_superblock(inode->i_sb);
if (!(sbsec->flags & SBLABEL_MNT))
return -EOPNOTSUPP;
@@ -6647,6 +6633,7 @@ struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
.lbs_inode = sizeof(struct inode_security_struct),
.lbs_ipc = sizeof(struct ipc_security_struct),
.lbs_msg_msg = sizeof(struct msg_security_struct),
+ .lbs_superblock = sizeof(struct superblock_security_struct),
};
static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
@@ -6675,7 +6662,6 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
- LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
diff --git a/security/selinux/include/objsec.h b/security/selinux/include/objsec.h
index 231262d8eac9..d08d7e5d2f93 100644
--- a/security/selinux/include/objsec.h
+++ b/security/selinux/include/objsec.h
@@ -188,4 +188,10 @@ static inline struct ipc_security_struct *selinux_ipc(
return ipc->security + selinux_blob_sizes.lbs_ipc;
}
+static inline struct superblock_security_struct *selinux_superblock(
+ const struct super_block *superblock)
+{
+ return superblock->s_security + selinux_blob_sizes.lbs_superblock;
+}
+
#endif /* _SELINUX_OBJSEC_H_ */
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index ec62918521b1..e3f5d6aece66 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -50,6 +50,7 @@
#include <linux/audit.h>
#include <linux/mutex.h>
#include <linux/vmalloc.h>
+#include <linux/lsm_hooks.h>
#include <net/netlabel.h>
#include "flask.h"
@@ -2751,7 +2752,7 @@ int security_fs_use(struct selinux_state *state, struct super_block *sb)
struct sidtab *sidtab;
int rc = 0;
struct ocontext *c;
- struct superblock_security_struct *sbsec = sb->s_security;
+ struct superblock_security_struct *sbsec = selinux_superblock(sb);
const char *fstype = sb->s_type->name;
read_lock(&state->ss->policy_rwlock);
diff --git a/security/smack/smack.h b/security/smack/smack.h
index cf52af77d15e..caecbcba9942 100644
--- a/security/smack/smack.h
+++ b/security/smack/smack.h
@@ -375,6 +375,12 @@ static inline struct smack_known **smack_ipc(const struct kern_ipc_perm *ipc)
return ipc->security + smack_blob_sizes.lbs_ipc;
}
+static inline struct superblock_smack *smack_superblock(
+ const struct super_block *superblock)
+{
+ return superblock->s_security + smack_blob_sizes.lbs_superblock;
+}
+
/*
* Is the directory transmuting?
*/
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 5c1613519d5a..807eff2ccce9 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -540,12 +540,7 @@ static int smack_syslog(int typefrom_file)
*/
static int smack_sb_alloc_security(struct super_block *sb)
{
- struct superblock_smack *sbsp;
-
- sbsp = kzalloc(sizeof(struct superblock_smack), GFP_KERNEL);
-
- if (sbsp == NULL)
- return -ENOMEM;
+ struct superblock_smack *sbsp = smack_superblock(sb);
sbsp->smk_root = &smack_known_floor;
sbsp->smk_default = &smack_known_floor;
@@ -554,22 +549,10 @@ static int smack_sb_alloc_security(struct super_block *sb)
/*
* SMK_SB_INITIALIZED will be zero from kzalloc.
*/
- sb->s_security = sbsp;
return 0;
}
-/**
- * smack_sb_free_security - free a superblock blob
- * @sb: the superblock getting the blob
- *
- */
-static void smack_sb_free_security(struct super_block *sb)
-{
- kfree(sb->s_security);
- sb->s_security = NULL;
-}
-
struct smack_mnt_opts {
const char *fsdefault, *fsfloor, *fshat, *fsroot, *fstransmute;
};
@@ -781,7 +764,7 @@ static int smack_set_mnt_opts(struct super_block *sb,
{
struct dentry *root = sb->s_root;
struct inode *inode = d_backing_inode(root);
- struct superblock_smack *sp = sb->s_security;
+ struct superblock_smack *sp = smack_superblock(sb);
struct inode_smack *isp;
struct smack_known *skp;
struct smack_mnt_opts *opts = mnt_opts;
@@ -880,7 +863,7 @@ static int smack_set_mnt_opts(struct super_block *sb,
*/
static int smack_sb_statfs(struct dentry *dentry)
{
- struct superblock_smack *sbp = dentry->d_sb->s_security;
+ struct superblock_smack *sbp = smack_superblock(dentry->d_sb);
int rc;
struct smk_audit_info ad;
@@ -917,7 +900,7 @@ static int smack_bprm_set_creds(struct linux_binprm *bprm)
if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task)
return 0;
- sbsp = inode->i_sb->s_security;
+ sbsp = smack_superblock(inode->i_sb);
if ((sbsp->smk_flags & SMK_SB_UNTRUSTED) &&
isp->smk_task != sbsp->smk_root)
return 0;
@@ -1168,7 +1151,7 @@ static int smack_inode_rename(struct inode *old_inode,
*/
static int smack_inode_permission(struct inode *inode, int mask)
{
- struct superblock_smack *sbsp = inode->i_sb->s_security;
+ struct superblock_smack *sbsp = smack_superblock(inode->i_sb);
struct smk_audit_info ad;
int no_block = mask & MAY_NOT_BLOCK;
int rc;
@@ -1410,7 +1393,7 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name)
*/
if (strcmp(name, XATTR_NAME_SMACK) == 0) {
struct super_block *sbp = dentry->d_sb;
- struct superblock_smack *sbsp = sbp->s_security;
+ struct superblock_smack *sbsp = smack_superblock(sbp);
isp->smk_inode = sbsp->smk_default;
} else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0)
@@ -1680,7 +1663,7 @@ static int smack_mmap_file(struct file *file,
isp = smack_inode(file_inode(file));
if (isp->smk_mmap == NULL)
return 0;
- sbsp = file_inode(file)->i_sb->s_security;
+ sbsp = smack_superblock(file_inode(file)->i_sb);
if (sbsp->smk_flags & SMK_SB_UNTRUSTED &&
isp->smk_mmap != sbsp->smk_root)
return -EACCES;
@@ -3288,7 +3271,7 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
goto unlockandout;
sbp = inode->i_sb;
- sbsp = sbp->s_security;
+ sbsp = smack_superblock(sbp);
/*
* We're going to use the superblock default label
* if there's no label on the file.
@@ -4575,6 +4558,7 @@ struct lsm_blob_sizes smack_blob_sizes __lsm_ro_after_init = {
.lbs_inode = sizeof(struct inode_smack),
.lbs_ipc = sizeof(struct smack_known *),
.lbs_msg_msg = sizeof(struct smack_known *),
+ .lbs_superblock = sizeof(struct superblock_smack),
};
static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
@@ -4586,7 +4570,6 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(fs_context_parse_param, smack_fs_context_parse_param),
LSM_HOOK_INIT(sb_alloc_security, smack_sb_alloc_security),
- LSM_HOOK_INIT(sb_free_security, smack_sb_free_security),
LSM_HOOK_INIT(sb_free_mnt_opts, smack_free_mnt_opts),
LSM_HOOK_INIT(sb_eat_lsm_opts, smack_sb_eat_lsm_opts),
LSM_HOOK_INIT(sb_statfs, smack_sb_statfs),
--
2.20.1
^ permalink raw reply related
* Re: [PATCH 6/9] Add a general, global device notification watch list [ver #5]
From: Greg Kroah-Hartman @ 2019-07-03 19:08 UTC (permalink / raw)
To: David Howells
Cc: viro, Casey Schaufler, Stephen Smalley, nicolas.dichtel, raven,
Christian Brauner, keyrings, linux-usb, linux-security-module,
linux-fsdevel, linux-api, linux-block, linux-kernel
In-Reply-To: <156173697086.15137.9549379251509621554.stgit@warthog.procyon.org.uk>
On Fri, Jun 28, 2019 at 04:49:30PM +0100, David Howells wrote:
> Create a general, global watch list that can be used for the posting of
> device notification events, for such things as device attachment,
> detachment and errors on sources such as block devices and USB devices.
> This can be enabled with:
>
> CONFIG_DEVICE_NOTIFICATIONS
>
> To add a watch on this list, an event queue must be created and configured:
>
> fd = open("/dev/event_queue", O_RDWR);
> ioctl(fd, IOC_WATCH_QUEUE_SET_SIZE, page_size << n);
>
> and then a watch can be placed upon it using a system call:
>
> watch_devices(fd, 12, 0);
>
> Unless the application wants to receive all events, it should employ
> appropriate filters.
Ok, as discussed off-list, this is needed by the other patches
afterward, i.e. the USB and block ones, which makes more sense.
Some tiny nits:
> diff --git a/drivers/base/watch.c b/drivers/base/watch.c
> new file mode 100644
> index 000000000000..00336607dc73
> --- /dev/null
> +++ b/drivers/base/watch.c
> @@ -0,0 +1,90 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Event notifications.
> + *
> + * Copyright (C) 2019 Red Hat, Inc. All Rights Reserved.
> + * Written by David Howells (dhowells@redhat.com)
> + */
> +
> +#include <linux/watch_queue.h>
> +#include <linux/syscalls.h>
> +#include <linux/init_task.h>
> +#include <linux/security.h>
You forgot to include device.h which has the prototype for your global
function :)
> +
> +/*
> + * Global queue for watching for device layer events.
> + */
> +static struct watch_list device_watchers = {
> + .watchers = HLIST_HEAD_INIT,
> + .lock = __SPIN_LOCK_UNLOCKED(&device_watchers.lock),
> +};
> +
> +static DEFINE_SPINLOCK(device_watchers_lock);
> +
> +/**
> + * post_device_notification - Post notification of a device event
> + * @n - The notification to post
> + * @id - The device ID
> + *
> + * Note that there's only a global queue to which all events are posted. Might
> + * want to provide per-dev queues also.
> + */
> +void post_device_notification(struct watch_notification *n, u64 id)
> +{
> + post_watch_notification(&device_watchers, n, &init_cred, id);
> +}
Don't you need to export this symbol?
> +
> +/**
> + * sys_watch_devices - Watch for device events.
> + * @watch_fd: The watch queue to send notifications to.
> + * @watch_id: The watch ID to be placed in the notification (-1 to remove watch)
> + * @flags: Flags (reserved for future)
> + */
> +SYSCALL_DEFINE3(watch_devices, int, watch_fd, int, watch_id, unsigned int, flags)
Finally, the driver core gets a syscall! :)
Don't we need a manpage and a kselftest for it?
> +{
> + struct watch_queue *wqueue;
> + struct watch_list *wlist = &device_watchers;
No real need for wlist, right? You just set it to this value and then
it never changes?
> + struct watch *watch;
> + long ret = -ENOMEM;
> + u64 id = 0; /* Might want to allow dev# here. */
I don't understand the comment here, what does "dev#" refer to?
> +
> + if (watch_id < -1 || watch_id > 0xff || flags)
> + return -EINVAL;
> +
> + wqueue = get_watch_queue(watch_fd);
> + if (IS_ERR(wqueue)) {
> + ret = PTR_ERR(wqueue);
> + goto err;
> + }
> +
> + if (watch_id >= 0) {
> + watch = kzalloc(sizeof(*watch), GFP_KERNEL);
> + if (!watch)
> + goto err_wqueue;
> +
> + init_watch(watch, wqueue);
> + watch->id = id;
> + watch->info_id = (u32)watch_id << WATCH_INFO_ID__SHIFT;
> +
> + ret = security_watch_devices(watch);
> + if (ret < 0)
> + goto err_watch;
> +
> + spin_lock(&device_watchers_lock);
> + ret = add_watch_to_object(watch, wlist);
> + spin_unlock(&device_watchers_lock);
> + if (ret == 0)
> + watch = NULL;
> + } else {
> + spin_lock(&device_watchers_lock);
> + ret = remove_watch_from_object(wlist, wqueue, id, false);
> + spin_unlock(&device_watchers_lock);
> + }
> +
> +err_watch:
> + kfree(watch);
> +err_wqueue:
> + put_watch_queue(wqueue);
> +err:
> + return ret;
> +}
> diff --git a/include/linux/device.h b/include/linux/device.h
> index e85264fb6616..c947c078b1be 100644
> --- a/include/linux/device.h
> +++ b/include/linux/device.h
> @@ -26,6 +26,7 @@
> #include <linux/uidgid.h>
> #include <linux/gfp.h>
> #include <linux/overflow.h>
> +#include <linux/watch_queue.h>
No need for this, just do:
struct watch_notification;
so that things build.
thanks,
greg k-h
^ permalink raw reply
* Re: [PATCH 6/9] Add a general, global device notification watch list [ver #5]
From: Greg Kroah-Hartman @ 2019-07-03 17:16 UTC (permalink / raw)
To: David Howells
Cc: viro, Casey Schaufler, Stephen Smalley, nicolas.dichtel, raven,
Christian Brauner, keyrings, linux-usb, linux-security-module,
linux-fsdevel, linux-api, linux-block, linux-kernel
In-Reply-To: <156173697086.15137.9549379251509621554.stgit@warthog.procyon.org.uk>
On Fri, Jun 28, 2019 at 04:49:30PM +0100, David Howells wrote:
> Create a general, global watch list that can be used for the posting of
> device notification events, for such things as device attachment,
> detachment and errors on sources such as block devices and USB devices.
> This can be enabled with:
>
> CONFIG_DEVICE_NOTIFICATIONS
>
> To add a watch on this list, an event queue must be created and configured:
>
> fd = open("/dev/event_queue", O_RDWR);
> ioctl(fd, IOC_WATCH_QUEUE_SET_SIZE, page_size << n);
>
> and then a watch can be placed upon it using a system call:
>
> watch_devices(fd, 12, 0);
>
> Unless the application wants to receive all events, it should employ
> appropriate filters.
What "filter"? Who is going to use this and why a new system call for
this? You can do this today with udev/netlink/hotplug/whatever so why
create yet-another-way?
I don't think this is a good idea unless we really nail down the api and
who is going to be using it.
thanks,
greg k-h
^ permalink raw reply
* Re: [PATCH 4/9] General notification queue with user mmap()'able ring buffer [ver #5]
From: Greg Kroah-Hartman @ 2019-07-03 17:11 UTC (permalink / raw)
To: David Howells
Cc: viro, Casey Schaufler, Stephen Smalley, nicolas.dichtel, raven,
Christian Brauner, keyrings, linux-usb, linux-security-module,
linux-fsdevel, linux-api, linux-block, linux-kernel
In-Reply-To: <156173695061.15137.17196611619288074120.stgit@warthog.procyon.org.uk>
On Fri, Jun 28, 2019 at 04:49:10PM +0100, David Howells wrote:
> Implement a misc device that implements a general notification queue as a
> ring buffer that can be mmap()'d from userspace.
>
> The way this is done is:
>
> (1) An application opens the device and indicates the size of the ring
> buffer that it wants to reserve in pages (this can only be set once):
>
> fd = open("/dev/watch_queue", O_RDWR);
> ioctl(fd, IOC_WATCH_QUEUE_NR_PAGES, nr_of_pages);
>
> (2) The application should then map the pages that the device has
> reserved. Each instance of the device created by open() allocates
> separate pages so that maps of different fds don't interfere with one
> another. Multiple mmap() calls on the same fd, however, will all work
> together.
>
> page_size = sysconf(_SC_PAGESIZE);
> mapping_size = nr_of_pages * page_size;
> char *buf = mmap(NULL, mapping_size, PROT_READ|PROT_WRITE,
> MAP_SHARED, fd, 0);
>
> The ring is divided into 8-byte slots. Entries written into the ring are
> variable size and can use between 1 and 63 slots. A special entry is
> maintained in the first two slots of the ring that contains the head and
> tail pointers. This is skipped when the ring wraps round. Note that
> multislot entries, therefore, aren't allowed to be broken over the end of
> the ring, but instead "skip" entries are inserted to pad out the buffer.
>
> Each entry has a 1-slot header that describes it:
>
> struct watch_notification {
> __u32 type:24;
> __u32 subtype:8;
> __u32 info;
> };
>
> The type indicates the source (eg. mount tree changes, superblock events,
> keyring changes, block layer events) and the subtype indicates the event
> type (eg. mount, unmount; EIO, EDQUOT; link, unlink). The info field
> indicates a number of things, including the entry length, an ID assigned to
> a watchpoint contributing to this buffer, type-specific flags and meta
> flags, such as an overrun indicator.
>
> Supplementary data, such as the key ID that generated an event, are
> attached in additional slots.
>
> Signed-off-by: David Howells <dhowells@redhat.com>
I don't know if I mentioned this before, but your naming seems a bit
"backwards" from other subsystems. Should "watch_queue" always be the
prefix, instead of a mix of prefix/suffix usage?
Anyway, your call, it's your code :)
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
^ permalink raw reply
* Re: [PATCH 1/9] uapi: General notification ring definitions [ver #5]
From: Greg Kroah-Hartman @ 2019-07-03 17:08 UTC (permalink / raw)
To: David Howells
Cc: viro, Casey Schaufler, Stephen Smalley, nicolas.dichtel, raven,
Christian Brauner, keyrings, linux-usb, linux-security-module,
linux-fsdevel, linux-api, linux-block, linux-kernel
In-Reply-To: <156173691411.15137.2073887155273175167.stgit@warthog.procyon.org.uk>
On Fri, Jun 28, 2019 at 04:48:34PM +0100, David Howells wrote:
> Add UAPI definitions for the general notification ring, including the
> following pieces:
>
> (1) struct watch_notification.
>
> This is the metadata header for each entry in the ring. It includes a
> type and subtype that indicate the source of the message
> (eg. WATCH_TYPE_MOUNT_NOTIFY) and the kind of the message
> (eg. NOTIFY_MOUNT_NEW_MOUNT).
>
> The header also contains an information field that conveys the
> following information:
>
> - WATCH_INFO_LENGTH. The size of the entry (entries are variable
> length).
>
> - WATCH_INFO_ID. The watch ID specified when the watchpoint was
> set.
>
> - WATCH_INFO_TYPE_INFO. (Sub)type-specific information.
>
> - WATCH_INFO_FLAG_*. Flag bits overlain on the type-specific
> information. For use by the type.
>
> All the information in the header can be used in filtering messages at
> the point of writing into the buffer.
>
> (2) struct watch_queue_buffer.
>
> This describes the layout of the ring. Note that the first slots in
> the ring contain a special metadata entry that contains the ring
> pointers. The producer in the kernel knows to skip this and it has a
> proper header (WATCH_TYPE_META, WATCH_META_SKIP_NOTIFICATION) that
> indicates the size so that the ring consumer can handle it the same as
> any other record and just skip it.
>
> Note that this means that ring entries can never be split over the end
> of the ring, so if an entry would need to be split, a skip record is
> inserted to wrap the ring first; this is also WATCH_TYPE_META,
> WATCH_META_SKIP_NOTIFICATION.
>
> (3) WATCH_INFO_NOTIFICATIONS_LOST.
>
> This is a flag that can be set in the metadata header by the kernel to
> indicate that at least one message was lost since it was last cleared
> by userspace.
>
> Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
^ permalink raw reply
* Re: [PATCH 8/9] usb: Add USB subsystem notifications [ver #5]
From: Greg Kroah-Hartman @ 2019-07-03 17:07 UTC (permalink / raw)
To: David Howells
Cc: viro, Casey Schaufler, Stephen Smalley, nicolas.dichtel, raven,
Christian Brauner, keyrings, linux-usb, linux-security-module,
linux-fsdevel, linux-api, linux-block, linux-kernel
In-Reply-To: <156173698939.15137.11150923486478934112.stgit@warthog.procyon.org.uk>
On Fri, Jun 28, 2019 at 04:49:49PM +0100, David Howells wrote:
> Add a USB subsystem notification mechanism whereby notifications about
> hardware events such as device connection, disconnection, reset and I/O
> errors, can be reported to a monitoring process asynchronously.
>
> Firstly, an event queue needs to be created:
>
> fd = open("/dev/event_queue", O_RDWR);
> ioctl(fd, IOC_WATCH_QUEUE_SET_SIZE, page_size << n);
>
> then a notification can be set up to report USB notifications via that
> queue:
>
> struct watch_notification_filter filter = {
> .nr_filters = 1,
> .filters = {
> [0] = {
> .type = WATCH_TYPE_USB_NOTIFY,
> .subtype_filter[0] = UINT_MAX;
> },
> },
> };
> ioctl(fd, IOC_WATCH_QUEUE_SET_FILTER, &filter);
> notify_devices(fd, 12);
>
> After that, records will be placed into the queue when events occur on a
> USB device or bus. Records are of the following format:
>
> struct usb_notification {
> struct watch_notification watch;
> __u32 error;
> __u32 reserved;
> __u8 name_len;
> __u8 name[0];
> } *n;
>
> Where:
>
> n->watch.type will be WATCH_TYPE_USB_NOTIFY
>
> n->watch.subtype will be the type of notification, such as
> NOTIFY_USB_DEVICE_ADD.
>
> n->watch.info & WATCH_INFO_LENGTH will indicate the length of the
> record.
>
> n->watch.info & WATCH_INFO_ID will be the second argument to
> device_notify(), shifted.
>
> n->error and n->reserved are intended to convey information such as
> error codes, but are currently not used
>
> n->name_len and n->name convey the USB device name as an
> unterminated string. This may be truncated - it is currently
> limited to a maximum 63 chars.
>
> Note that it is permissible for event records to be of variable length -
> or, at least, the length may be dependent on the subtype.
>
> Signed-off-by: David Howells <dhowells@redhat.com>
> cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> cc: linux-usb@vger.kernel.org
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
^ permalink raw reply
* Re: [RFC PATCH v2 1/3] x86/sgx: Add SGX specific LSM hooks
From: Casey Schaufler @ 2019-07-03 15:32 UTC (permalink / raw)
To: Dr. Greg, casey
Cc: Xing, Cedric, Stephen Smalley, linux-sgx@vger.kernel.org,
linux-security-module@vger.kernel.org, selinux@vger.kernel.org,
Schaufler, Casey, jmorris@namei.org, luto@kernel.org,
jethro@fortanix.com, sds@tycho.nsa.gov,
jarkko.sakkinen@linux.intel.com, Christopherson, Sean J
In-Reply-To: <20190703094651.GA29601@wind.enjellic.com>
On 7/3/2019 2:46 AM, Dr. Greg wrote:
> On Tue, Jul 02, 2019 at 08:44:40AM -0700, Casey Schaufler wrote:
>
> Good morning, I hope this note finds the week going well for everyone.
>
>> On 7/2/2019 12:42 AM, Xing, Cedric wrote:
>>> ...
>>> Guess this discussion will never end if we don't get into
>>> code. Guess it'd be more productive to talk over phone then come back
>>> to this thread with a conclusion. Will that be ok with you?
>> I don't think that a phone call is going to help. Talking code
>> issues tends to muddle them in my brain. If you can give me a few
>> days I will propose a rough version of how I think your code should
>> be integrated into the LSM environment. I'm spending more time
>> trying (unsuccessfully :( ) to discribe the issues in English than
>> it will probably take in C.
> While Casey is off writing his rosetta stone,
I'd hardly call it that. More of an effort to round the
corners on the square peg. And Cedric has some ideas on
how to approach that.
> let me suggest that the
> most important thing we need to do is to take a little time, step back
> and look at the big picture with respect to what we are trying to
> accomplish and if we are going about it in a way that makes any sense
> from an engineering perspective.
>
> This conversation shouldn't be about SGX, it should be about the best
> way for the kernel/LSM to discipline a Trusted Execution Environment
> (TEE). As I have noted previously, a TEE is a 'blackbox' that, by
> design, is intended to allow execution of code and processing of data
> in a manner that is resistant to manipulation or inspection by
> untrusted userspace, the kernel and/or the hardware itself.
>
> Given that fact, if we are to be intellectually honest, we need to ask
> ourselves how effective we believe we can be in controlling any TEE
> with kernel based mechanisms. This is particularly the case if the
> author of any code running in the TEE has adversarial intent.
>
> Here is the list of controls that we believe an LSM can, effectively,
> implement against a TEE:
>
> 1.) Code provenance and origin.
>
> 2.) Cryptographic verification of dynamically executable content.
>
> 2.) The ability of a TEE to implement anonymous executable content.
>
> If people are in agreement with this concept, it is difficult to
> understand why we should be implementing complex state machines and
> the like, whether it is in the driver or the LSM. Security code has
> to be measured with a metric of effectiveness, otherwise we are
> engaging in security theater.
>
> I believe that if we were using this lens, we would already have a
> mainline SGX driver, since we seem to have most of the needed LSM
> infrastructure and any additional functionality would be a straight
> forward implementation. Most importantly, the infrastructure would
> not be SGX specific, which would seem to be a desirable political
> concept.
Generality introduced in the absence of multiple instances
often results in unnecessary complexity, unused interfaces
and feature compromise. Guessing what other TEE systems might
do, and constraining SGX to those models (or the other way around)
is a well established road to ruin. The LSM infrastructure is
a fine example. For the first ten years the "general" mechanism
had a single user. I'd say to hold off on the general until there
is more experience with the specific. It's easier to construct
a general mechanism around things that work than to fit things
that need to work into some preconceived notion of generality.
>
> If we are not willing to engage in this discussion we are going to end
> up with a quasi-technology specific solution that isn't implementing
> any relevant security guarantees.
>
> FWIW, we wouldn't even be having this, now lengthy discussion, if I
> wouldn't have aggressively advocated, starting last November, that an
> SGX driver needed some form of execution control if there was a desire
> for the technology to not pose a security risk to the platform. So
> humor me a little bit.... :-)
>
> Best wishes for a productive remainder of the week to everyone.
>
> Dr. Greg
>
> As always,
> Dr. Greg Wettstein, Ph.D, Worker
> IDfusion, LLC
> 4206 N. 19th Ave. Implementing measured information privacy
> Fargo, ND 58102 and integrity architectures.
> PH: 701-281-1686
> FAX: 701-281-3949 EMAIL: greg@idfusion.net
> ------------------------------------------------------------------------------
> "... remember that innovation is saying 'no' to 1000 things."
^ permalink raw reply
* Re: [PATCH -next] integrity: Remove set but not used variable 'acl'
From: David Howells @ 2019-07-03 13:57 UTC (permalink / raw)
To: YueHaibing
Cc: dhowells, James Morris, Serge E. Hallyn, Kairui Song,
Thomas Gleixner, Mimi Zohar, Thiago Jung Bauermann, Nayna Jain,
Eric Biggers, linux-security-module, linux-kernel,
kernel-janitors
In-Reply-To: <20190703025518.6379-1-yuehaibing@huawei.com>
YueHaibing <yuehaibing@huawei.com> wrote:
> Fixes gcc '-Wunused-but-set-variable' warning:
>
> security/integrity/digsig.c: In function 'integrity_init_keyring':
> security/integrity/digsig.c:99:18: warning:
> variable 'acl' set but not used [-Wunused-but-set-variable]
>
> It seems 'acl' is needed in __integrity_init_keyring
I've folded this fix in, thanks.
David
^ permalink raw reply
* Re: [PATCH v10 1/2] mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options
From: Alexander Potapenko @ 2019-07-03 11:40 UTC (permalink / raw)
To: Andrew Morton
Cc: Christoph Lameter, Kees Cook, Michal Hocko, James Morris,
Masahiro Yamada, Michal Hocko, James Morris, Serge E. Hallyn,
Nick Desaulniers, Kostya Serebryany, Dmitry Vyukov, Sandeep Patil,
Laura Abbott, Randy Dunlap, Jann Horn, Mark Rutland, Marco Elver,
Qian Cai, Linux Memory Management List, linux-security-module,
Kernel Hardening
In-Reply-To: <20190702155915.ab5e7053e5c0d49e84c6ed67@linux-foundation.org>
On Wed, Jul 3, 2019 at 12:59 AM Andrew Morton <akpm@linux-foundation.org> wrote:
>
> On Fri, 28 Jun 2019 11:31:30 +0200 Alexander Potapenko <glider@google.com> wrote:
>
> > The new options are needed to prevent possible information leaks and
> > make control-flow bugs that depend on uninitialized values more
> > deterministic.
> >
> > This is expected to be on-by-default on Android and Chrome OS. And it
> > gives the opportunity for anyone else to use it under distros too via
> > the boot args. (The init_on_free feature is regularly requested by
> > folks where memory forensics is included in their threat models.)
> >
> > init_on_alloc=1 makes the kernel initialize newly allocated pages and heap
> > objects with zeroes. Initialization is done at allocation time at the
> > places where checks for __GFP_ZERO are performed.
> >
> > init_on_free=1 makes the kernel initialize freed pages and heap objects
> > with zeroes upon their deletion. This helps to ensure sensitive data
> > doesn't leak via use-after-free accesses.
> >
> > Both init_on_alloc=1 and init_on_free=1 guarantee that the allocator
> > returns zeroed memory. The two exceptions are slab caches with
> > constructors and SLAB_TYPESAFE_BY_RCU flag. Those are never
> > zero-initialized to preserve their semantics.
> >
> > Both init_on_alloc and init_on_free default to zero, but those defaults
> > can be overridden with CONFIG_INIT_ON_ALLOC_DEFAULT_ON and
> > CONFIG_INIT_ON_FREE_DEFAULT_ON.
> >
> > If either SLUB poisoning or page poisoning is enabled, those options
> > take precedence over init_on_alloc and init_on_free: initialization is
> > only applied to unpoisoned allocations.
> >
> > Slowdown for the new features compared to init_on_free=0,
> > init_on_alloc=0:
> >
> > hackbench, init_on_free=1: +7.62% sys time (st.err 0.74%)
> > hackbench, init_on_alloc=1: +7.75% sys time (st.err 2.14%)
> >
> > Linux build with -j12, init_on_free=1: +8.38% wall time (st.err 0.39%)
> > Linux build with -j12, init_on_free=1: +24.42% sys time (st.err 0.52%)
> > Linux build with -j12, init_on_alloc=1: -0.13% wall time (st.err 0.42%)
> > Linux build with -j12, init_on_alloc=1: +0.57% sys time (st.err 0.40%)
> >
> > The slowdown for init_on_free=0, init_on_alloc=0 compared to the
> > baseline is within the standard error.
> >
> > The new features are also going to pave the way for hardware memory
> > tagging (e.g. arm64's MTE), which will require both on_alloc and on_free
> > hooks to set the tags for heap objects. With MTE, tagging will have the
> > same cost as memory initialization.
> >
> > Although init_on_free is rather costly, there are paranoid use-cases where
> > in-memory data lifetime is desired to be minimized. There are various
> > arguments for/against the realism of the associated threat models, but
> > given that we'll need the infrastructure for MTE anyway, and there are
> > people who want wipe-on-free behavior no matter what the performance cost,
> > it seems reasonable to include it in this series.
> >
> > ...
> >
> > v10:
> > - added Acked-by: tags
> > - converted pr_warn() to pr_info()
>
> There are unchangelogged alterations between v9 and v10. The
> replacement of IS_ENABLED(CONFIG_PAGE_POISONING)) with
> page_poisoning_enabled().
In the case I send another version of the patch, do I need to
retroactively add them to the changelog?
>
> --- a/mm/page_alloc.c~mm-security-introduce-init_on_alloc=1-and-init_on_free=1-boot-options-v10
> +++ a/mm/page_alloc.c
> @@ -157,8 +157,8 @@ static int __init early_init_on_alloc(ch
> if (!buf)
> return -EINVAL;
> ret = kstrtobool(buf, &bool_result);
> - if (bool_result && IS_ENABLED(CONFIG_PAGE_POISONING))
> - pr_warn("mem auto-init: CONFIG_PAGE_POISONING is on, will take precedence over init_on_alloc\n");
> + if (bool_result && page_poisoning_enabled())
> + pr_info("mem auto-init: CONFIG_PAGE_POISONING is on, will take precedence over init_on_alloc\n");
> if (bool_result)
> static_branch_enable(&init_on_alloc);
> else
> @@ -175,8 +175,8 @@ static int __init early_init_on_free(cha
> if (!buf)
> return -EINVAL;
> ret = kstrtobool(buf, &bool_result);
> - if (bool_result && IS_ENABLED(CONFIG_PAGE_POISONING))
> - pr_warn("mem auto-init: CONFIG_PAGE_POISONING is on, will take precedence over init_on_free\n");
> + if (bool_result && page_poisoning_enabled())
> + pr_info("mem auto-init: CONFIG_PAGE_POISONING is on, will take precedence over init_on_free\n");
> if (bool_result)
> static_branch_enable(&init_on_free);
> else
> --- a/mm/slub.c~mm-security-introduce-init_on_alloc=1-and-init_on_free=1-boot-options-v10
> +++ a/mm/slub.c
> @@ -1281,9 +1281,8 @@ check_slabs:
> out:
> if ((static_branch_unlikely(&init_on_alloc) ||
> static_branch_unlikely(&init_on_free)) &&
> - (slub_debug & SLAB_POISON)) {
> - pr_warn("mem auto-init: SLAB_POISON will take precedence over init_on_alloc/init_on_free\n");
> - }
> + (slub_debug & SLAB_POISON))
> + pr_info("mem auto-init: SLAB_POISON will take precedence over init_on_alloc/init_on_free\n");
> return 1;
> }
>
> _
>
--
Alexander Potapenko
Software Engineer
Google Germany GmbH
Erika-Mann-Straße, 33
80636 München
Geschäftsführer: Paul Manicle, Halimah DeLaine Prado
Registergericht und -nummer: Hamburg, HRB 86891
Sitz der Gesellschaft: Hamburg
^ permalink raw reply
* Re: [PATCH] ima: Replace two seq_printf() calls by seq_puts() in ima_show_template_data_ascii()
From: Mimi Zohar @ 2019-07-03 11:14 UTC (permalink / raw)
To: David Laight, 'Markus Elfring',
linux-integrity@vger.kernel.org,
linux-security-module@vger.kernel.org, Dmitry Kasatkin,
James Morris, Serge E. Hallyn
Cc: LKML, kernel-janitors@vger.kernel.org
In-Reply-To: <d94bfdb9d53b46059787b9bdd10c5919@AcuMS.aculab.com>
On Wed, 2019-07-03 at 09:16 +0000, David Laight wrote:
> > diff --git a/security/integrity/ima/ima_template_lib.c b/security/integrity/ima/ima_template_lib.c
> > index 9fe0ef7f91e2..05636e9b19b1 100644
> > --- a/security/integrity/ima/ima_template_lib.c
> > +++ b/security/integrity/ima/ima_template_lib.c
> > @@ -74,7 +74,7 @@ static void ima_show_template_data_ascii(struct seq_file *m,
> > case DATA_FMT_DIGEST_WITH_ALGO:
> > buf_ptr = strnchr(field_data->data, buflen, ':');
> > if (buf_ptr != field_data->data)
> > - seq_printf(m, "%s", field_data->data);
> > + seq_puts(m, field_data->data);
> >
> > /* skip ':' and '\0' */
> > buf_ptr += 2;
>
> That code looks highly suspect!
> It uses a bounded scan then assumes a '\0' terminated string.
> It then adds 2 to a potentially NULL pointer.
The code here is used for displaying the IMA measurement list, that
the kernel itself created. Protecting the in kernel memory from
attack is a different problem. Refer to Igor Stoppa's write once
memory pools.
Mimi
^ permalink raw reply
* Re: [RFC PATCH v2 1/3] x86/sgx: Add SGX specific LSM hooks
From: Dr. Greg @ 2019-07-03 9:46 UTC (permalink / raw)
To: Casey Schaufler
Cc: Xing, Cedric, Stephen Smalley, linux-sgx@vger.kernel.org,
linux-security-module@vger.kernel.org, selinux@vger.kernel.org,
Schaufler, Casey, jmorris@namei.org, luto@kernel.org,
jethro@fortanix.com, sds@tycho.nsa.gov,
jarkko.sakkinen@linux.intel.com, Christopherson, Sean J
In-Reply-To: <9e45df1b-3aac-e851-4ef2-5b262f5139bd@schaufler-ca.com>
On Tue, Jul 02, 2019 at 08:44:40AM -0700, Casey Schaufler wrote:
Good morning, I hope this note finds the week going well for everyone.
> On 7/2/2019 12:42 AM, Xing, Cedric wrote:
> > ...
> > Guess this discussion will never end if we don't get into
> > code. Guess it'd be more productive to talk over phone then come back
> > to this thread with a conclusion. Will that be ok with you?
> I don't think that a phone call is going to help. Talking code
> issues tends to muddle them in my brain. If you can give me a few
> days I will propose a rough version of how I think your code should
> be integrated into the LSM environment. I'm spending more time
> trying (unsuccessfully :( ) to discribe the issues in English than
> it will probably take in C.
While Casey is off writing his rosetta stone, let me suggest that the
most important thing we need to do is to take a little time, step back
and look at the big picture with respect to what we are trying to
accomplish and if we are going about it in a way that makes any sense
from an engineering perspective.
This conversation shouldn't be about SGX, it should be about the best
way for the kernel/LSM to discipline a Trusted Execution Environment
(TEE). As I have noted previously, a TEE is a 'blackbox' that, by
design, is intended to allow execution of code and processing of data
in a manner that is resistant to manipulation or inspection by
untrusted userspace, the kernel and/or the hardware itself.
Given that fact, if we are to be intellectually honest, we need to ask
ourselves how effective we believe we can be in controlling any TEE
with kernel based mechanisms. This is particularly the case if the
author of any code running in the TEE has adversarial intent.
Here is the list of controls that we believe an LSM can, effectively,
implement against a TEE:
1.) Code provenance and origin.
2.) Cryptographic verification of dynamically executable content.
2.) The ability of a TEE to implement anonymous executable content.
If people are in agreement with this concept, it is difficult to
understand why we should be implementing complex state machines and
the like, whether it is in the driver or the LSM. Security code has
to be measured with a metric of effectiveness, otherwise we are
engaging in security theater.
I believe that if we were using this lens, we would already have a
mainline SGX driver, since we seem to have most of the needed LSM
infrastructure and any additional functionality would be a straight
forward implementation. Most importantly, the infrastructure would
not be SGX specific, which would seem to be a desirable political
concept.
If we are not willing to engage in this discussion we are going to end
up with a quasi-technology specific solution that isn't implementing
any relevant security guarantees.
FWIW, we wouldn't even be having this, now lengthy discussion, if I
wouldn't have aggressively advocated, starting last November, that an
SGX driver needed some form of execution control if there was a desire
for the technology to not pose a security risk to the platform. So
humor me a little bit.... :-)
Best wishes for a productive remainder of the week to everyone.
Dr. Greg
As always,
Dr. Greg Wettstein, Ph.D, Worker
IDfusion, LLC
4206 N. 19th Ave. Implementing measured information privacy
Fargo, ND 58102 and integrity architectures.
PH: 701-281-1686
FAX: 701-281-3949 EMAIL: greg@idfusion.net
------------------------------------------------------------------------------
"... remember that innovation is saying 'no' to 1000 things."
^ permalink raw reply
* Re: ima: Replace two seq_printf() calls by seq_puts() in ima_show_template_data_ascii()
From: Markus Elfring @ 2019-07-03 9:33 UTC (permalink / raw)
To: David Laight, linux-integrity, linux-security-module
Cc: Dmitry Kasatkin, James Morris, Mimi Zohar, Serge E. Hallyn, LKML,
kernel-janitors
In-Reply-To: <d94bfdb9d53b46059787b9bdd10c5919@AcuMS.aculab.com>
> So this is probably just a minor performance improvement in a code
> path where it really doesn't matter.
I imagine that another small software adjustment can help a bit
to get nicer run time characteristics also at this place.
>> +++ b/security/integrity/ima/ima_template_lib.c
>> @@ -74,7 +74,7 @@ static void ima_show_template_data_ascii(struct seq_file *m,
>> case DATA_FMT_DIGEST_WITH_ALGO:
>> buf_ptr = strnchr(field_data->data, buflen, ':');
>> if (buf_ptr != field_data->data)
>> - seq_printf(m, "%s", field_data->data);
>> + seq_puts(m, field_data->data);
>>
>> /* skip ':' and '\0' */
>> buf_ptr += 2;
>
> That code looks highly suspect!
Would you like to change this implementation detail any more?
Regards,
Markus
^ permalink raw reply
* RE: [PATCH] ima: Replace two seq_printf() calls by seq_puts() in ima_show_template_data_ascii()
From: David Laight @ 2019-07-03 9:16 UTC (permalink / raw)
To: 'Markus Elfring', linux-integrity@vger.kernel.org,
linux-security-module@vger.kernel.org, Dmitry Kasatkin,
James Morris, Mimi Zohar, Serge E. Hallyn
Cc: LKML, kernel-janitors@vger.kernel.org
In-Reply-To: <e96eac40-0745-80b5-6aab-f872e6415031@web.de>
From: Markus Elfring
> Sent: 02 July 2019 20:01
>
> From: Markus Elfring <elfring@users.sourceforge.net>
> Date: Tue, 2 Jul 2019 20:52:21 +0200
>
> Two strings which did not contain a data format specification should be put
> into a sequence. Thus use the corresponding function “seq_puts”.
>
> This issue was detected by using the Coccinelle software.
The two calls are almost certainly absolutely equivalent.
So this is probably just a minor performance improvement in a code
path where it really doesn't matter.
> Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
> ---
> security/integrity/ima/ima_template_lib.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/security/integrity/ima/ima_template_lib.c b/security/integrity/ima/ima_template_lib.c
> index 9fe0ef7f91e2..05636e9b19b1 100644
> --- a/security/integrity/ima/ima_template_lib.c
> +++ b/security/integrity/ima/ima_template_lib.c
> @@ -74,7 +74,7 @@ static void ima_show_template_data_ascii(struct seq_file *m,
> case DATA_FMT_DIGEST_WITH_ALGO:
> buf_ptr = strnchr(field_data->data, buflen, ':');
> if (buf_ptr != field_data->data)
> - seq_printf(m, "%s", field_data->data);
> + seq_puts(m, field_data->data);
>
> /* skip ':' and '\0' */
> buf_ptr += 2;
That code looks highly suspect!
It uses a bounded scan then assumes a '\0' terminated string.
It then adds 2 to a potentially NULL pointer.
About typical for 'security' code :-)
David
-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)
^ permalink raw reply
* [PATCH -next] integrity: Remove set but not used variable 'acl'
From: YueHaibing @ 2019-07-03 2:55 UTC (permalink / raw)
To: James Morris, Serge E. Hallyn, David Howells, Kairui Song,
Thomas Gleixner, Mimi Zohar, Thiago Jung Bauermann, Nayna Jain,
Eric Biggers
Cc: YueHaibing, linux-security-module, linux-kernel, kernel-janitors
Fixes gcc '-Wunused-but-set-variable' warning:
security/integrity/digsig.c: In function 'integrity_init_keyring':
security/integrity/digsig.c:99:18: warning:
variable 'acl' set but not used [-Wunused-but-set-variable]
It seems 'acl' is needed in __integrity_init_keyring
Fixes: 6100ac53909d ("keys: Replace uid/gid/perm permissions checking with an ACL")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
---
security/integrity/digsig.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c
index 1f2c43f62047..f9f3c8ffe786 100644
--- a/security/integrity/digsig.c
+++ b/security/integrity/digsig.c
@@ -114,7 +114,7 @@ int __init integrity_init_keyring(const unsigned int id)
acl = &internal_writable_keyring_acl;
out:
- return __integrity_init_keyring(id, &internal_keyring_acl, restriction);
+ return __integrity_init_keyring(id, acl, restriction);
}
static int __init integrity_add_key(const unsigned int id, const void *data,
^ permalink raw reply related
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