Re: [Qemu-devel] [PATCH v4 7/7] block/nbd: NBDReply is used being uninitialized

[Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>]

On 19/07/2019 17:34, Eric Blake wrote:
> On 7/19/19 4:40 AM, Andrey Shinkevich wrote:
>> In case nbd_co_receive_one_chunk() fails in
>> nbd_reply_chunk_iter_receive(), 'NBDReply reply' parameter is used in
>> the check nbd_reply_is_simple() without being initialized. The iotest
>> 083 does not pass under the Valgrind: $./check -nbd -valgrind 083.
>> The alternative solution is to swap the operands in the condition:
>> 'if (s->quit || nbd_reply_is_simple(reply))'
>>
>> Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
>> ---
>>   block/nbd.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> Huh. Very similar to
> https://lists.gnu.org/archive/html/qemu-devel/2019-07/msg03712.html, but
> affects a different function. I can queue this one through my NBD tree
> to get both in my rc2 pull request.
> 
> Reviewed-by: Eric Blake <eblake@redhat.com>
> 

Many thanks,
Andrey

>>
>> diff --git a/block/nbd.c b/block/nbd.c
>> index 81edabb..8480ad4 100644
>> --- a/block/nbd.c
>> +++ b/block/nbd.c
>> @@ -786,7 +786,7 @@ static int nbd_co_receive_cmdread_reply(BDRVNBDState *s, uint64_t handle,
>>                                           int *request_ret, Error **errp)
>>   {
>>       NBDReplyChunkIter iter;
>> -    NBDReply reply;
>> +    NBDReply reply = {};
>>       void *payload = NULL;
>>       Error *local_err = NULL;
>>   
>>
> 

-- 
With the best regards,
Andrey Shinkevich