From 1be49cee34eb588d70c2bf4c46dc23539fd71b53 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sat, 17 Feb 2018 04:20:54 +0100 Subject: [PATCH] avcodec/h264: Increase field_poc to 64bit in ff_h264_init_poc() to detect overflows Fixes: Integer overflow Fixes: 5746/clusterfuzz-testcase-minimized-6270097623613440 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/h264_parse.c | 6 +++++- libavcodec/h264_parser.c | 4 +++- libavcodec/h264_slice.c | 4 +++- 3 files changed, 11 insertions(+), 3 deletions(-) diff --git a/libavcodec/h264_parse.c b/libavcodec/h264_parse.c index fee28d90d9..6cbef5a13d 100644 --- a/libavcodec/h264_parse.c +++ b/libavcodec/h264_parse.c @@ -271,7 +271,7 @@ int ff_h264_init_poc(int pic_field_poc[2], int *pic_poc, int picture_structure, int nal_ref_idc) { const int max_frame_num = 1 << sps->log2_max_frame_num; - int field_poc[2]; + int64_t field_poc[2]; pc->frame_num_offset = pc->prev_frame_num_offset; if (pc->frame_num < pc->prev_frame_num) @@ -337,6 +337,10 @@ int ff_h264_init_poc(int pic_field_poc[2], int *pic_poc, field_poc[1] = poc; } + if ( field_poc[0] != (int)field_poc[0] + || field_poc[1] != (int)field_poc[1]) + return AVERROR_INVALIDDATA; + if (picture_structure != PICT_BOTTOM_FIELD) pic_field_poc[0] = field_poc[0]; if (picture_structure != PICT_TOP_FIELD) diff --git a/libavcodec/h264_parser.c b/libavcodec/h264_parser.c index 65d9d44b50..1a9840a62c 100644 --- a/libavcodec/h264_parser.c +++ b/libavcodec/h264_parser.c @@ -449,8 +449,10 @@ static inline int parse_nal_units(AVCodecParserContext *s, /* Decode POC of this picture. * The prev_ values needed for decoding POC of the next picture are not set here. */ field_poc[0] = field_poc[1] = INT_MAX; - ff_h264_init_poc(field_poc, &s->output_picture_number, sps, + ret = ff_h264_init_poc(field_poc, &s->output_picture_number, sps, &p->poc, p->picture_structure, nal.ref_idc); + if (ret < 0) + goto fail; /* Continue parsing to check if MMCO_RESET is present. * FIXME: MMCO_RESET could appear in non-first slice. diff --git a/libavcodec/h264_slice.c b/libavcodec/h264_slice.c index e6b7998834..90e05ed8f1 100644 --- a/libavcodec/h264_slice.c +++ b/libavcodec/h264_slice.c @@ -1607,8 +1607,10 @@ static int h264_field_start(H264Context *h, const H264SliceContext *sl, (h->mb_height * h->mb_stride - 1) * sizeof(*h->slice_table)); } - ff_h264_init_poc(h->cur_pic_ptr->field_poc, &h->cur_pic_ptr->poc, + ret = ff_h264_init_poc(h->cur_pic_ptr->field_poc, &h->cur_pic_ptr->poc, h->ps.sps, &h->poc, h->picture_structure, nal->ref_idc); + if (ret < 0) + return ret; memcpy(h->mmco, sl->mmco, sl->nb_mmco * sizeof(*h->mmco)); h->nb_mmco = sl->nb_mmco;