Michael Niedermayer: > Fixes: NULL pointer dereference > Fixes: > 68184/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_APNG_fuzzer-4926478069334016 > > Found-by: continuous fuzzing process > https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > Signed-off-by: Michael Niedermayer <mich...@niedermayer.cc> > --- > libavcodec/pngdec.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/libavcodec/pngdec.c b/libavcodec/pngdec.c > index f7751223b81..b24bfa248dc 100644 > --- a/libavcodec/pngdec.c > +++ b/libavcodec/pngdec.c > @@ -1218,7 +1218,7 @@ static int decode_fctl_chunk(AVCodecContext *avctx, > PNGDecContext *s, > return AVERROR_INVALIDDATA; > } > > - if ((sequence_number == 0 || !s->last_picture.f->data[0]) && > + if ((sequence_number == 0 || !s->last_picture.f || > !s->last_picture.f->data[0]) && > dispose_op == APNG_DISPOSE_OP_PREVIOUS) { > // No previous frame to revert to for the first frame > // Spec says to just treat it as a APNG_DISPOSE_OP_BACKGROUND
Just checking for !s->last_picture.f is enough -- s->last_picture.f is set if and only if s->last_picture.f->data[0] is set. - Andreas _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
