Fixes: out of array read Fixes: 15286/clusterfuzz-testcase-minimized-ffmpeg_DEMUXER_fuzzer-5658245101780992
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <mich...@niedermayer.cc> --- libavformat/vividas.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/libavformat/vividas.c b/libavformat/vividas.c index 753328245d..350c7aa70a 100644 --- a/libavformat/vividas.c +++ b/libavformat/vividas.c @@ -178,12 +178,13 @@ static void decode_block(uint8_t *src, uint8_t *dest, unsigned size, } } -static uint32_t get_v(uint8_t *p) +static uint32_t get_v(uint8_t *p, int len) { uint32_t v = 0; + const uint8_t *end = p + len; do { - if (v >= UINT_MAX / 128 - *p) + if (p >= end || v >= UINT_MAX / 128 - *p) return v; v <<= 7; v += *p & 0x7f; @@ -204,7 +205,7 @@ static uint8_t *read_vblock(AVIOContext *src, uint32_t *size, decode_block(tmp, tmp, 4, key, k2, align); - n = get_v(tmp); + n = get_v(tmp, 4); if (n < 4) return NULL; @@ -241,13 +242,13 @@ static uint8_t *read_sb_block(AVIOContext *src, unsigned *size, k2 = *key; decode_block(ibuf, sbuf, 8, *key, &k2, 0); - n = get_v(sbuf+2); + n = get_v(sbuf+2, 6); if (sbuf[0] != 'S' || sbuf[1] != 'B' || (expected_size>0 && n != expected_size)) { uint32_t tmpkey = recover_key(ibuf, expected_size); k2 = tmpkey; decode_block(ibuf, sbuf, 8, tmpkey, &k2, 0); - n = get_v(sbuf+2); + n = get_v(sbuf+2, 6); if (sbuf[0] != 'S' || sbuf[1] != 'B' || expected_size != n) return NULL; *key = tmpkey; -- 2.22.0 _______________________________________________ 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".
