Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758716AbaKUPH3 (ORCPT ); Fri, 21 Nov 2014 10:07:29 -0500 Received: from mail-ie0-f179.google.com ([209.85.223.179]:49183 "EHLO mail-ie0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758358AbaKUPH0 (ORCPT ); Fri, 21 Nov 2014 10:07:26 -0500 From: Pranith Kumar To: Kees Cook , Andy Lutomirski , Will Drewry , linux-kernel@vger.kernel.org (open list) Subject: [PATCH v2 7/9] seccomp: Replace smp_read_barrier_depends() with lockless_dereference() Date: Fri, 21 Nov 2014 10:06:01 -0500 Message-Id: <1416582363-20661-8-git-send-email-bobby.prani@gmail.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1416582363-20661-1-git-send-email-bobby.prani@gmail.com> References: <1416582363-20661-1-git-send-email-bobby.prani@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- kernel/seccomp.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 4ef9687..3729b06 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; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/