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| author | Paul Moore <paul@paul-moore.com> | 2021-09-29 17:01:21 +0200 |
|---|---|---|
| committer | Paul Moore <paul@paul-moore.com> | 2021-11-22 23:52:47 +0100 |
| commit | 6326948f940dc3f77066d5cdc44ba6afe67830c0 (patch) | |
| tree | 13976c9bfaedfc1105ac27a1efaf9c752d3949ee /security/selinux/hooks.c | |
| parent | Linux 5.16-rc1 (diff) | |
| download | linux-6326948f940dc3f77066d5cdc44ba6afe67830c0.tar.xz linux-6326948f940dc3f77066d5cdc44ba6afe67830c0.zip | |
lsm: security_task_getsecid_subj() -> security_current_getsecid_subj()
The security_task_getsecid_subj() LSM hook invites misuse by allowing
callers to specify a task even though the hook is only safe when the
current task is referenced. Fix this by removing the task_struct
argument to the hook, requiring LSM implementations to use the
current task. While we are changing the hook declaration we also
rename the function to security_current_getsecid_subj() in an effort
to reinforce that the hook captures the subjective credentials of the
current task and not an arbitrary task on the system.
Reviewed-by: Serge Hallyn <serge@hallyn.com>
Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Diffstat (limited to 'security/selinux/hooks.c')
| -rw-r--r-- | security/selinux/hooks.c | 19 |
1 files changed, 3 insertions, 16 deletions
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 62d30c0a30c2..726175254f60 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -230,19 +230,6 @@ static inline u32 cred_sid(const struct cred *cred) } /* - * get the subjective security ID of a task - */ -static inline u32 task_sid_subj(const struct task_struct *task) -{ - u32 sid; - - rcu_read_lock(); - sid = cred_sid(rcu_dereference(task->cred)); - rcu_read_unlock(); - return sid; -} - -/* * get the objective security ID of a task */ static inline u32 task_sid_obj(const struct task_struct *task) @@ -4205,9 +4192,9 @@ static int selinux_task_getsid(struct task_struct *p) PROCESS__GETSESSION, NULL); } -static void selinux_task_getsecid_subj(struct task_struct *p, u32 *secid) +static void selinux_current_getsecid_subj(u32 *secid) { - *secid = task_sid_subj(p); + *secid = current_sid(); } static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid) @@ -7159,7 +7146,7 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid), LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid), LSM_HOOK_INIT(task_getsid, selinux_task_getsid), - LSM_HOOK_INIT(task_getsecid_subj, selinux_task_getsecid_subj), + LSM_HOOK_INIT(current_getsecid_subj, selinux_current_getsecid_subj), LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj), LSM_HOOK_INIT(task_setnice, selinux_task_setnice), LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio), |