seccomp: Replace smp_read_barrier_depends() with lockless_dereference()
Recently lockless_dereference() was added which can be used in place of
hard-coding smp_read_barrier_depends(). The following PATCH makes the change.
Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
diff --git a/kernel/seccomp.c b/kernel/seccomp.c
index 4f44028..980fd26 100644
--- a/kernel/seccomp.c
+++ b/kernel/seccomp.c
@@ -175,17 +175,16 @@
*/
static u32 seccomp_run_filters(struct seccomp_data *sd)
{
- struct seccomp_filter *f = ACCESS_ONCE(current->seccomp.filter);
struct seccomp_data sd_local;
u32 ret = SECCOMP_RET_ALLOW;
+ /* Make sure cross-thread synced filter points somewhere sane. */
+ struct seccomp_filter *f =
+ lockless_dereference(current->seccomp.filter);
/* Ensure unexpected behavior doesn't result in failing open. */
if (unlikely(WARN_ON(f == NULL)))
return SECCOMP_RET_KILL;
- /* Make sure cross-thread synced filter points somewhere sane. */
- smp_read_barrier_depends();
-
if (!sd) {
populate_seccomp_data(&sd_local);
sd = &sd_local;
