From: Michael Niedermayer Date: Tue, 30 Mar 2021 11:22:14 +0000 (+0200) Subject: avcodec/pnm_parser: Check image size addition for overflow X-Git-Url: https://git.sesse.net/?a=commitdiff_plain;h=79ac8d55468adc9cb9a0908e671807a2a789b7d0;p=ffmpeg avcodec/pnm_parser: Check image size addition for overflow Fixes: assertion failure Fixes: out of array access Fixes: 32664/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_PGMYUV_fuzzer-6533642202513408.fuzz Fixes: 32669/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_PGMYUV_fuzzer-6001928875147264 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- diff --git a/libavcodec/pnm_parser.c b/libavcodec/pnm_parser.c index f3be6d640cd..a822c17a2e9 100644 --- a/libavcodec/pnm_parser.c +++ b/libavcodec/pnm_parser.c @@ -111,7 +111,7 @@ retry: } else { int ret = av_image_get_buffer_size(avctx->pix_fmt, avctx->width, avctx->height, 1); next = pnmctx.bytestream - pnmctx.bytestream_start + skip; - if (ret >= 0) + if (ret >= 0 && next + (uint64_t)ret <= INT_MAX) next += ret; } if (next != END_NOT_FOUND && pnmctx.bytestream_start != buf + skip)