[FFmpeg-devel] [PATCH] swresample/resample: do not allow negative dst_size return value

[Muhammad Faiz]

On 12/14/16, Michael Niedermayer <michael at niedermayer.cc> wrote:
> On Tue, Dec 13, 2016 at 11:15:30PM +0700, Muhammad Faiz wrote:
>> On 12/13/16, Michael Niedermayer <michael at niedermayer.cc> wrote:
>> > On Tue, Dec 13, 2016 at 02:16:03PM +0700, Muhammad Faiz wrote:
>> >> This should fix Ticket6012
>> >>
>> >> Signed-off-by: Muhammad Faiz <mfcc64 at gmail.com>
>> >> ---
>> >>  libswresample/resample.c | 7 ++++---
>> >>  1 file changed, 4 insertions(+), 3 deletions(-)
>> >>
>> >> diff --git a/libswresample/resample.c b/libswresample/resample.c
>> >> index 71dffb9..ce6a82f 100644
>> >> --- a/libswresample/resample.c
>> >> +++ b/libswresample/resample.c
>> >> @@ -478,8 +478,9 @@ static int swri_resample(ResampleContext *c,
>> >>          int64_t incr= (1LL<<32) * c->dst_incr / c->src_incr;
>> >>          int new_size = (src_size * (int64_t)c->src_incr - frac +
>> >> c->dst_incr - 1) / c->dst_incr;
>> >>
>> >> -        dst_size= FFMIN(dst_size, new_size);
>> >> -        c->dsp.resample_one(dst, src, dst_size, index2, incr);
>> >> +        dst_size = FFMAX(FFMIN(dst_size, new_size), 0);
>> >> +        if (dst_size > 0)
>> >> +            c->dsp.resample_one(dst, src, dst_size, index2, incr);
>> >>
>> >>          index += dst_size * c->dst_incr_div;
>> >>          index += (frac + dst_size * (int64_t)c->dst_incr_mod) /
>> >> c->src_incr;
>> >> @@ -494,7 +495,7 @@ static int swri_resample(ResampleContext *c,
>> >>          int64_t delta_frac = (end_index - c->index) * c->src_incr -
>> >> c->frac;
>> >>          int delta_n = (delta_frac + c->dst_incr - 1) / c->dst_incr;
>> >>
>> >> -        dst_size = FFMIN(dst_size, delta_n);
>> >> +        dst_size = FFMAX(FFMIN(dst_size, delta_n), 0);
>> >
>> > Shouldnt this and other things be done outside the loop that
>> > calls swri_resample() ?
>>
>> For performance reason probably yes, even swri_resample should be
>> integrated
>> to multiple_resample to avoid redundant calculations.
>>
>> But this is bugfix patch, and swri_resample should return proper
>> dst_size.
>> I just follow current code flow.
>>
>> Patch that improve performance is outside the scope of this patch.
>> Probably
>> I will post that if this patch is accepted.
>
> LGTM
>
> thx

Applied

Thank's