From 99bab6e96168e205ffa990369684fee41e367934 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Tue, 24 Jan 2023 22:48:46 +0100 Subject: [PATCH] avcodec/g2meet: Replace fake allocation avoidance for framebuf framebuf is only allocated when the new width/height are larger than the old but nothing sets the old so its always allocated. Use av_fast_mallocz() instead. Fixes: Timeout Fixes: 55094/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_G2M_fuzzer-5116909932904448 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit 38adbc6eebd7f2f34ecf1b0b18019e88bad9d9f4) Signed-off-by: Michael Niedermayer --- libavcodec/g2meet.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/libavcodec/g2meet.c b/libavcodec/g2meet.c index 7ef275c9fe..5856d51783 100644 --- a/libavcodec/g2meet.c +++ b/libavcodec/g2meet.c @@ -143,7 +143,8 @@ typedef struct G2MContext { int got_header; uint8_t *framebuf; - int framebuf_stride, old_width, old_height; + int framebuf_stride; + unsigned int framebuf_allocated; uint8_t *synth_tile, *jpeg_tile, *epic_buf, *epic_buf_base; int tile_stride, epic_buf_stride, old_tile_w, old_tile_h; @@ -1179,14 +1180,13 @@ static int g2m_init_buffers(G2MContext *c) { int aligned_height; - if (!c->framebuf || c->old_width < c->width || c->old_height < c->height) { - c->framebuf_stride = FFALIGN(c->width + 15, 16) * 3; - aligned_height = c->height + 15; - av_free(c->framebuf); - c->framebuf = av_mallocz_array(c->framebuf_stride, aligned_height); - if (!c->framebuf) - return AVERROR(ENOMEM); - } + c->framebuf_stride = FFALIGN(c->width + 15, 16) * 3; + aligned_height = c->height + 15; + + av_fast_mallocz(&c->framebuf, &c->framebuf_allocated, c->framebuf_stride * aligned_height); + if (!c->framebuf) + return AVERROR(ENOMEM); + if (!c->synth_tile || !c->jpeg_tile || (c->compression == 2 && !c->epic_buf_base) || c->old_tile_w < c->tile_width || @@ -1638,6 +1638,7 @@ static av_cold int g2m_decode_end(AVCodecContext *avctx) av_freep(&c->jpeg_tile); av_freep(&c->cursor); av_freep(&c->framebuf); + c->framebuf_allocated = 0; return 0; }