From c54b9fc42fee613e2c4c0dae2052ff94cd15e254 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Thu, 31 Oct 2019 14:38:16 +0100 Subject: [PATCH] avcodec/wmadec: Require previous exponents for reuse Fixes: division by zero Fixes: 18474/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WMAV2_fuzzer-5764986962182144 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/wma.h | 1 + libavcodec/wmadec.c | 3 +++ 2 files changed, 4 insertions(+) diff --git a/libavcodec/wma.h b/libavcodec/wma.h index 325f03c44b..8344cb5b93 100644 --- a/libavcodec/wma.h +++ b/libavcodec/wma.h @@ -123,6 +123,7 @@ typedef struct WMACodecContext { uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + AV_INPUT_BUFFER_PADDING_SIZE]; /* padding added */ int last_bitoffset; int last_superframe_len; + int exponents_initialized; float noise_table[NOISE_TAB_SIZE]; int noise_index; float noise_mult; /* XXX: suppress that and integrate it in the noise array */ diff --git a/libavcodec/wmadec.c b/libavcodec/wmadec.c index 78b51e5871..bb9bc8d236 100644 --- a/libavcodec/wmadec.c +++ b/libavcodec/wmadec.c @@ -587,6 +587,9 @@ static int wma_decode_block(WMACodecContext *s) s->exponents_bsize[ch] = bsize; } } + s->exponents_initialized = 1; + }else if (!s->exponents_initialized) { + return AVERROR_INVALIDDATA; } /* parse spectral coefficients : just RLE encoding */