From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:39477 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754008AbaHUS4x (ORCPT ); Thu, 21 Aug 2014 14:56:53 -0400 Message-ID: <53F640F1.1010104@redhat.com> Date: Thu, 21 Aug 2014 13:56:49 -0500 From: Eric Sandeen MIME-Version: 1.0 To: Gui Hecheng , linux-btrfs@vger.kernel.org CC: marvin24@gmx.de Subject: Re: [PATCH] btrfs-progs: init uninitialized output buf for btrfs-restore References: <1408592136-7606-1-git-send-email-guihc.fnst@cn.fujitsu.com> <53F63D8F.2080400@redhat.com> In-Reply-To: <53F63D8F.2080400@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 8/21/14, 1:42 PM, Eric Sandeen wrote: > On 8/20/14, 10:35 PM, Gui Hecheng wrote: >> A memory problem reported by valgrind as follows: >> === Syscall param pwrite64(buf) points to uninitialised byte(s) >> When running: >> # valgrind --leak-check=yes btrfs restore /dev/sda9 /mnt/backup >> >> Because the output buf size is alloced with malloc, but the length of >> output data is shorter than the sizeof(buf), so valgrind report >> uninitialised byte(s). >> We could use calloc to repalce malloc and clear this WARNING away. > > It clears the valgrind error away, but does it hide a real bug? Maybe the relevant question for Marc is - did you get decompression errors during restore? if so then I guess it all makes sense, and the proposed patch seems sane after all, sorry. -Eric