From 65d426bddd0b9210788bf9be7af21b80b30d422a Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Tue, 16 Dec 2014 21:14:40 +0100 Subject: [PATCH] avformat/mov: check atom nesting depth Fixes call stack overflow Fixes: case1_call_stack_overflow.mp4 Found-by: Michal Zalewski Signed-off-by: Michael Niedermayer (cherry picked from commit caa7a3914f499f74b3ee346f26d598ebdc0ec210) Conflicts: libavformat/isom.h --- libavformat/isom.h | 1 + libavformat/mov.c | 13 ++++++++++++- 2 files changed, 13 insertions(+), 1 deletion(-) diff --git a/libavformat/isom.h b/libavformat/isom.h index 979e967d14..6fb0c4d41b 100644 --- a/libavformat/isom.h +++ b/libavformat/isom.h @@ -171,6 +171,7 @@ typedef struct MOVContext { int *bitrates; ///< bitrates read before streams creation int bitrates_count; int moov_retry; + int atom_depth; } MOVContext; int ff_mp4_read_descr_len(AVIOContext *pb); diff --git a/libavformat/mov.c b/libavformat/mov.c index ae48c02287..06037174b5 100644 --- a/libavformat/mov.c +++ b/libavformat/mov.c @@ -3172,6 +3172,12 @@ static int mov_read_default(MOVContext *c, AVIOContext *pb, MOVAtom atom) MOVAtom a; int i; + if (c->atom_depth > 10) { + av_log(c->fc, AV_LOG_ERROR, "Atoms too deeply nested\n"); + return AVERROR_INVALIDDATA; + } + c->atom_depth ++; + if (atom.size < 0) atom.size = INT64_MAX; while (total_size + 8 <= atom.size && !avio_feof(pb)) { @@ -3201,6 +3207,7 @@ static int mov_read_default(MOVContext *c, AVIOContext *pb, MOVAtom atom) { av_log(c->fc, AV_LOG_ERROR, "Broken file, trak/mdat not at top-level\n"); avio_skip(pb, -8); + c->atom_depth --; return 0; } } @@ -3237,13 +3244,16 @@ static int mov_read_default(MOVContext *c, AVIOContext *pb, MOVAtom atom) int64_t start_pos = avio_tell(pb); int64_t left; int err = parse(c, pb, a); - if (err < 0) + if (err < 0) { + c->atom_depth --; return err; + } if (c->found_moov && c->found_mdat && ((!pb->seekable || c->fc->flags & AVFMT_FLAG_IGNIDX) || start_pos + a.size == avio_size(pb))) { if (!pb->seekable || c->fc->flags & AVFMT_FLAG_IGNIDX) c->next_root_atom = start_pos + a.size; + c->atom_depth --; return 0; } left = a.size - avio_tell(pb) + start_pos; @@ -3263,6 +3273,7 @@ static int mov_read_default(MOVContext *c, AVIOContext *pb, MOVAtom atom) if (total_size < atom.size && atom.size < 0x7ffff) avio_skip(pb, atom.size - total_size); + c->atom_depth --; return 0; }