Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751560Ab3JUQhx (ORCPT ); Mon, 21 Oct 2013 12:37:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59536 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751261Ab3JUQhv (ORCPT ); Mon, 21 Oct 2013 12:37:51 -0400 Date: Mon, 21 Oct 2013 12:37:32 -0400 From: Dave Jones To: Greg Kroah-Hartman Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, Dave Jones , Theodore Tso , Eric Sandeen Subject: Re: [ 05/11] ext4: fix memory leak in xattr Message-ID: <20131021163732.GA16581@redhat.com> Mail-Followup-To: Dave Jones , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, stable@vger.kernel.org, Dave Jones , Theodore Tso , Eric Sandeen References: <20131018195049.069623827@linuxfoundation.org> <20131018195049.436649568@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20131018195049.436649568@linuxfoundation.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1821 Lines: 55 On Fri, Oct 18, 2013 at 12:53:34PM -0700, Greg Kroah-Hartman wrote: > 3.4-stable review patch. If anyone has any objections, please let me know. > > ------------------ > > From: Dave Jones > > commit 6e4ea8e33b2057b85d75175dd89b93f5e26de3bc upstream. > > If we take the 2nd retry path in ext4_expand_extra_isize_ea, we > potentionally return from the function without having freed these > allocations. If we don't do the return, we over-write the previous > allocation pointers, so we leak either way. > > Spotted with Coverity. > > [ Fixed by tytso to set is and bs to NULL after freeing these > pointers, in case in the retry loop we later end up triggering an > error causing a jump to cleanup, at which point we could have a double > free bug. -- Ted ] > > Signed-off-by: Dave Jones > Signed-off-by: "Theodore Ts'o" > Reviewed-by: Eric Sandeen > Signed-off-by: Greg Kroah-Hartman I'm still waiting to hear if we also need this.. Ted ? -- If we take the retry path here, we end up potentially overwriting bh, leaving it with an elevated reference count. Signed-off-by: Dave Jones diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c index 03e9beb..1423c48 100644 --- a/fs/ext4/xattr.c +++ b/fs/ext4/xattr.c @@ -1352,6 +1352,7 @@ retry: new_extra_isize = s_min_extra_isize; kfree(is); is = NULL; kfree(bs); bs = NULL; + brelse(bh); goto retry; } error = -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/