Commit 4a9b1654 authored May 13, 2026 by Stephen Smalley Committed by Paul Moore May 14, 2026

lsm: hold cred_guard_mutex for lsm_set_self_attr()



Just as proc_pid_attr_write() already does before calling the LSM
hook. This only matters for SELinux and AppArmor which check
whether the process is being ptraced and if so, whether to
allow the transition.

Cc: stable@vger.kernel.org
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

parent 254f4963

security/lsm_syscalls.c

+8 −1

Original line number	Diff line number	Diff line
		@@ -57,7 +57,14 @@ u64 lsm_name_to_attr(const char *name)
		SYSCALL_DEFINE4(lsm_set_self_attr, unsigned int, attr, struct lsm_ctx __user *,
		ctx, u32, size, u32, flags)
		{
		return security_setselfattr(attr, ctx, size, flags);
		int rc;

		rc = mutex_lock_interruptible(&current->signal->cred_guard_mutex);
		if (rc < 0)
		return rc;
		rc = security_setselfattr(attr, ctx, size, flags);
		mutex_unlock(&current->signal->cred_guard_mutex);
		return rc;
		}

		/**