From 8225d3853f34f6cf9caff15d8c385a528e0d7cb1 Mon Sep 17 00:00:00 2001 From: Pranith Kumar Date: Fri, 21 Nov 2014 10:06:01 -0500 Subject: [PATCH] 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 Signed-off-by: Kees Cook --- kernel/seccomp.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 4f44028943e6..980fd26da22e 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -175,17 +175,16 @@ static int seccomp_check_filter(struct sock_filter *filter, unsigned int flen) */ 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;