Re: [PATCH] btrfs-progs: init uninitialized output buf for btrfs-restore

[Eric Sandeen <sandeen@redhat.com>]

On 8/22/14, 2:35 AM, Marc Dietrich wrote:
> Hi Eric,
> 
> Am Donnerstag, 21. August 2014, 13:56:49 schrieb Eric Sandeen:
>> 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.
> 
> I use lzo and yes, I got decompression errors.

Ok, ignore me then, I'm sorry - it all makes sense, Gui's patch
included.  I didn't have my head on straight.

Thanks,
-Eric