[FFmpeg-cvslog] af_aresample: allocate at least 1 sample buffer. Fix null ptr dereference.

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michaelni at gmx.at> | Mon Nov 19 15:55:23 2012 +0100| [c44a028e19c89671dbd614c283f7e5fe2f555139] | committer: Michael Niedermayer

af_aresample: allocate at least 1 sample buffer. Fix null ptr dereference.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni at gmx.at>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=c44a028e19c89671dbd614c283f7e5fe2f555139
---

 libavfilter/af_aresample.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/libavfilter/af_aresample.c b/libavfilter/af_aresample.c
index 53c5dcd..7201d37 100644
--- a/libavfilter/af_aresample.c
+++ b/libavfilter/af_aresample.c
@@ -174,12 +174,11 @@ static int filter_samples(AVFilterLink *inlink, AVFilterBufferRef *insamplesref)
 {
     AResampleContext *aresample = inlink->dst->priv;
     const int n_in  = insamplesref->audio->nb_samples;
-    int n_out       = n_in * aresample->ratio * 2 ;
+    int n_out       = FFMAX(n_in * aresample->ratio * 2, 1);
     AVFilterLink *const outlink = inlink->dst->outputs[0];
     AVFilterBufferRef *outsamplesref = ff_get_audio_buffer(outlink, AV_PERM_WRITE, n_out);
     int ret;
 
-
     avfilter_copy_buffer_ref_props(outsamplesref, insamplesref);
     outsamplesref->format                = outlink->format;
     outsamplesref->audio->channel_layout = outlink->channel_layout;