From 172a43ce36e671fdab63afe1c06876bba91445b3 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Mon, 15 Jul 2019 23:26:05 +0200 Subject: [PATCH] avcodec/sanm: Check extradata_size before allocations Fixes: Leaks Fixes: 15349/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_SANM_fuzzer-5102530557640704 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/sanm.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/libavcodec/sanm.c b/libavcodec/sanm.c index 25aee7220f..d0000ebd0c 100644 --- a/libavcodec/sanm.c +++ b/libavcodec/sanm.c @@ -491,6 +491,11 @@ static av_cold int decode_init(AVCodecContext *avctx) ctx->avctx = avctx; ctx->version = !avctx->extradata_size; + // early sanity check before allocations to avoid need for deallocation code. + if (!ctx->version && avctx->extradata_size < 1026) { + av_log(avctx, AV_LOG_ERROR, "Not enough extradata.\n"); + return AVERROR_INVALIDDATA; + } avctx->pix_fmt = ctx->version ? AV_PIX_FMT_RGB565 : AV_PIX_FMT_PAL8; @@ -506,11 +511,6 @@ static av_cold int decode_init(AVCodecContext *avctx) if (!ctx->version) { int i; - if (avctx->extradata_size < 1026) { - av_log(avctx, AV_LOG_ERROR, "Not enough extradata.\n"); - return AVERROR_INVALIDDATA; - } - ctx->subversion = AV_RL16(avctx->extradata); for (i = 0; i < PALETTE_SIZE; i++) ctx->pal[i] = 0xFFU << 24 | AV_RL32(avctx->extradata + 2 + i * 4);