From f4916e5c97d89ece33e96e7fe850f84d89559a76 Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michael@niedermayer.cc>
Date: Tue, 30 Mar 2021 13:22:14 +0200
Subject: [PATCH] avcodec/pnm_parser: Check image size addition for overflow
Fixes: assertion failure
Fixes: out of array access
Fixes: 32664/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_PGMYUV_fuzzer-6533642202513408.fuzz
Fixes: 32669/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_PGMYUV_fuzzer-6001928875147264
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 79ac8d55468adc9cb9a0908e671807a2a789b7d0)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
libavcodec/pnm_parser.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/libavcodec/pnm_parser.c b/libavcodec/pnm_parser.c
index 036ee97914..bdb2d07823 100644
--- a/libavcodec/pnm_parser.c
+++ b/libavcodec/pnm_parser.c
@@ -62,7 +62,7 @@ retry:
} else {
int ret = av_image_get_buffer_size(avctx->pix_fmt, avctx->width, avctx->height, 1);
next = pnmctx.bytestream - pnmctx.bytestream_start;
- if (ret >= 0)
+ if (ret >= 0 && next + (uint64_t)ret <= INT_MAX)
next += ret;
if (pnmctx.bytestream_start != buf)
next -= pc->index;