PR #21339 opened by Timo Rothenpieler (BtbN) URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/21339 Patch URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/21339.patch
(cherry picked from commit f6a95c7eb786f895812adaaa08d2fe91c4d4caf8) >From 80e99378c3f5d0e0c70a2ecf94faaae07a754a17 Mon Sep 17 00:00:00 2001 From: Timo Rothenpieler <[email protected]> Date: Wed, 31 Dec 2025 03:41:21 +0100 Subject: [PATCH] avformat/img2dec: reject input images too big to fit into a single packet Not entirely sure if it should instead use some entirely different approach here, given that images exceeding 2GB don't seem that crazy to me, but so far processing such images results in a heap overflow, since the size addition overflows and a much too small packet is allocated and its size never checked again when writing into it. Fixes #YWH-PGM40646-32 (cherry picked from commit f6a95c7eb786f895812adaaa08d2fe91c4d4caf8) --- libavformat/img2dec.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/libavformat/img2dec.c b/libavformat/img2dec.c index e2b4b01587..35558662fa 100644 --- a/libavformat/img2dec.c +++ b/libavformat/img2dec.c @@ -414,8 +414,10 @@ int ff_img_read_packet(AVFormatContext *s1, AVPacket *pkt) char filename_bytes[1024]; char *filename = filename_bytes; int i, res; - int size[3] = { 0 }, ret[3] = { 0 }; - AVIOContext *f[3] = { NULL }; + int ret[3] = { 0 }; + int64_t size[3] = { 0 }; + int64_t total_size; + AVIOContext *f[3] = { NULL }; AVCodecParameters *par = s1->streams[0]->codecpar; if (!s->is_pipe) { @@ -495,7 +497,17 @@ int ff_img_read_packet(AVFormatContext *s1, AVPacket *pkt) } } - res = av_new_packet(pkt, size[0] + size[1] + size[2]); + total_size = size[0]; + if (total_size > INT64_MAX - size[1]) + return AVERROR_INVALIDDATA; + total_size += size[1]; + if (total_size > INT64_MAX - size[2]) + return AVERROR_INVALIDDATA; + total_size += size[2]; + if (total_size > INT_MAX) + return AVERROR_INVALIDDATA; + + res = av_new_packet(pkt, total_size); if (res < 0) { goto fail; } -- 2.49.1 _______________________________________________ ffmpeg-devel mailing list -- [email protected] To unsubscribe send an email to [email protected]
