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Subject: Re: [PATCH] btrfs-progs: init uninitialized output buf for
 btrfs-restore
From: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
To: Marc Dietrich <marvin24@gmx.de>
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Date: Thu, 21 Aug 2014 17:43:00 +0800
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On Thu, 2014-08-21 at 10:14 +0200, Marc Dietrich wrote:
> Hi Gui,
> 
> Am Donnerstag, 21. August 2014, 11:35:36 schrieb Gui Hecheng:
> > 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.
> 
> yes, the warning vanished. But the reads from free'd memory make me more 
> worring...

Ah, yeah, I am looking into it, hope that I can do some help :)

> Marc