Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932642AbaFJTy1 (ORCPT ); Tue, 10 Jun 2014 15:54:27 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:35624 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753761AbaFJTyR (ORCPT ); Tue, 10 Jun 2014 15:54:17 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Christoph Hellwig , Chuck Lever , Al Viro , Kamal Mostafa Subject: [PATCH 3.13 155/160] posix_acl: handle NULL ACL in posix_acl_equiv_mode Date: Tue, 10 Jun 2014 12:46:35 -0700 Message-Id: <1402429600-20477-156-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1402429600-20477-1-git-send-email-kamal@canonical.com> References: <1402429600-20477-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.13 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.13.11.3 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Christoph Hellwig commit 50c6e282bdf5e8dabf8d7cf7b162545a55645fd9 upstream. Various filesystems don't bother checking for a NULL ACL in posix_acl_equiv_mode, and thus can dereference a NULL pointer when it gets passed one. This usually happens from the NFS server, as the ACL tools never pass a NULL ACL, but instead of one representing the mode bits. Instead of adding boilerplat to all filesystems put this check into one place, which will allow us to remove the check from other filesystems as well later on. Signed-off-by: Christoph Hellwig Reported-by: Ben Greear Reported-by: Marco Munderloh , Cc: Chuck Lever Signed-off-by: Al Viro Signed-off-by: Kamal Mostafa --- fs/posix_acl.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/posix_acl.c b/fs/posix_acl.c index 8bd2135..3542f1f 100644 --- a/fs/posix_acl.c +++ b/fs/posix_acl.c @@ -158,6 +158,12 @@ posix_acl_equiv_mode(const struct posix_acl *acl, umode_t *mode_p) umode_t mode = 0; int not_equiv = 0; + /* + * A null ACL can always be presented as mode bits. + */ + if (!acl) + return 0; + FOREACH_ACL_ENTRY(pa, acl, pe) { switch (pa->e_tag) { case ACL_USER_OBJ: -- 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/