Re: [Qemu-devel] [PATCH] vnc: tight: Fix crash after 2GB of output

[Michael Tokarev]

04.03.2011 11:56, Corentin Chary wrote:
>>>
>>>     bytes = zstream->total_out - previous_out;
> 
> Good catch
> 
>> total_out isn't used by zlib internally, so if the resulting
>> "total" counter is not needed in qemu, we can just zero-out
>> the total_out in this function before calling zlib, and
>> use the resulting value directly as "bytes", without
>> saving its previous value in previous_out.  Something like
>> the attached patch does.
> 
> If you're certain that total_out is not used by zlib, could you also
> send a patch for zlib encoding please ? (vnc-enc-zlib.c)
> Thanks,

Yes, I noticed this too (the same code is in enc-zlib), and mentioned
this in my previous email.

The attached slightly different patch fixes both places and fixes
them for good (hopefully anyway).  Runtime-tested for the tight
case, but honestly, I didn't wait for 2G of output ;)

Thanks!

/mjt

fix-vnc-zlib-overflow.diff
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