On 4/21/19, Michael Niedermayer <mich...@niedermayer.cc> wrote: > Fixes: SEGV on unknown address > Fixes: > 14198/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_AGM_fuzzer-5723579234123776 > > untested due to lack of valid samples using this codepath > > Found-by: continuous fuzzing process > https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > Signed-off-by: Michael Niedermayer <mich...@niedermayer.cc> > --- > libavcodec/agm.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/libavcodec/agm.c b/libavcodec/agm.c > index f3d81bf163..c9d7be5521 100644 > --- a/libavcodec/agm.c > +++ b/libavcodec/agm.c > @@ -919,7 +919,7 @@ static void get_tree_codes(uint32_t *codes, Node *nodes, > int idx, uint32_t pfx, > } > } > > -static void make_new_tree(const uint8_t *bitlens, uint32_t *codes) > +static int make_new_tree(const uint8_t *bitlens, uint32_t *codes) > { > int zlcount = 0, curlen, idx, nindex, last, llast; > int blcounts[32] = { 0 }; > @@ -959,6 +959,9 @@ static void make_new_tree(const uint8_t *bitlens, > uint32_t *codes) > int p = node_idx[nindex - 1 + 512]; > int ch = syms[256 * curlen + i]; > > + if (nindex <= 0) > + return AVERROR_INVALIDDATA; > + > if (nodes[p].child[0] == -1) { > nodes[p].child[0] = ch; > } else { > @@ -998,6 +1001,7 @@ static void make_new_tree(const uint8_t *bitlens, > uint32_t *codes) > next: > > get_tree_codes(codes, nodes, 256, 0, 0); > + return 0; > } > > static int build_huff(const uint8_t *bitlen, VLC *vlc) > @@ -1008,7 +1012,9 @@ static int build_huff(const uint8_t *bitlen, VLC *vlc) > uint32_t codes[256]; > int nb_codes = 0; > > - make_new_tree(bitlen, new_codes); > + int ret = make_new_tree(bitlen, new_codes); > + if (ret < 0) > + return ret; > > for (int i = 0; i < 256; i++) { > if (bitlen[i]) { > -- > 2.21.0 > > _______________________________________________ > 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".
LGTM _______________________________________________ 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".
