Michael Niedermayer: > On Fri, Oct 09, 2020 at 06:52:18PM +0200, Michael Niedermayer wrote: >> On Thu, Oct 08, 2020 at 09:48:41PM +0200, Andreas Rheinhardt wrote: >>> Michael Niedermayer: >>>> Fixes: shift exponent -1 is negative >>>> Fixes: >>>> 26107/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_PGX_fuzzer-5378790047612928 >>>> >>>> Found-by: continuous fuzzing process >>>> https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg >>>> Signed-off-by: Michael Niedermayer <mich...@niedermayer.cc> >>>> --- >>>> libavcodec/pgxdec.c | 6 +++--- >>>> 1 file changed, 3 insertions(+), 3 deletions(-) >>>> >>>> diff --git a/libavcodec/pgxdec.c b/libavcodec/pgxdec.c >>>> index 150f8bbf66..5c735894ab 100644 >>>> --- a/libavcodec/pgxdec.c >>>> +++ b/libavcodec/pgxdec.c >>>> @@ -133,14 +133,14 @@ static int pgx_decode_frame(AVCodecContext *avctx, >>>> void *data, >>>> if ((ret = ff_set_dimensions(avctx, width, height)) < 0) >>>> return ret; >>>> >>>> - if (depth <= 8) { >>>> + if (depth > 0 && depth <= 8) { >>>> avctx->pix_fmt = AV_PIX_FMT_GRAY8; >>>> bpp = 8; >>>> - } else if (depth <= 16) { >>>> + } else if (depth > 0 && depth <= 16) { >>>> avctx->pix_fmt = AV_PIX_FMT_GRAY16; >>>> bpp = 16; >>>> } else { >>>> - av_log(avctx, AV_LOG_ERROR, "Maximum depth of 16 bits >>>> supported.\n"); >>>> + av_log(avctx, AV_LOG_ERROR, "depth %d is invalid or >>>> unsupported.\n", depth); >>>> return AVERROR_PATCHWELCOME; >>>> } >>>> if (bytestream2_get_bytes_left(&g) < width * height * (bpp >> 3)) >>>> >>> I presume the parsed depth to be zero in your testcase. Said number >>> comes from pgx_get_number() which is only used to parse values for which >>> a value of zero makes no sense. Wouldn't it make more sense to error out >>> there if the number is zero? >> >> I was considering that too when i wrote the patch >> the reason why i picked this is thats where depth is checked already. >> Checking for depth == 0 in one function and depth > 16 in another feels >> like its not the clearest way to implement that ... > > ok if i apply this ? > or you still want it changed ? > I don't care. Proceed as you want.
- 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".
