From 120f74650d924f37285c73c6a78c8fc775b00c09 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Thu, 14 Sep 2023 22:27:46 +0200 Subject: [PATCH] avcodec/evc_ps: Check cpb_cnt_minus1 and propagate error Fixes: out of array access Fixes: 60949/clusterfuzz-testcase-minimized-ffmpeg_dem_EVC_fuzzer-5959738853294080 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer --- libavcodec/evc_ps.c | 27 +++++++++++++++++++++------ 1 file changed, 21 insertions(+), 6 deletions(-) diff --git a/libavcodec/evc_ps.c b/libavcodec/evc_ps.c index 6f93f5b373..be27386292 100644 --- a/libavcodec/evc_ps.c +++ b/libavcodec/evc_ps.c @@ -57,6 +57,9 @@ static int ref_pic_list_struct(const EVCParserSPS *sps, GetBitContext *gb, RefPi static int hrd_parameters(GetBitContext *gb, HRDParameters *hrd) { hrd->cpb_cnt_minus1 = get_ue_golomb_31(gb); + if (hrd->cpb_cnt_minus1 >= FF_ARRAY_ELEMS(hrd->cpb_size_value_minus1)) + return AVERROR_INVALIDDATA; + hrd->bit_rate_scale = get_bits(gb, 4); hrd->cpb_size_scale = get_bits(gb, 4); for (int SchedSelIdx = 0; SchedSelIdx <= hrd->cpb_cnt_minus1; SchedSelIdx++) { @@ -75,6 +78,8 @@ static int hrd_parameters(GetBitContext *gb, HRDParameters *hrd) // @see ISO_IEC_23094-1 (E.2.1 VUI parameters syntax) static int vui_parameters(GetBitContext *gb, VUIParameters *vui) { + int ret; + vui->aspect_ratio_info_present_flag = get_bits(gb, 1); if (vui->aspect_ratio_info_present_flag) { vui->aspect_ratio_idc = get_bits(gb, 8); @@ -113,11 +118,18 @@ static int vui_parameters(GetBitContext *gb, VUIParameters *vui) vui->fixed_pic_rate_flag = get_bits(gb, 1); } vui->nal_hrd_parameters_present_flag = get_bits(gb, 1); - if (vui->nal_hrd_parameters_present_flag) - hrd_parameters(gb, &vui->hrd_parameters); + if (vui->nal_hrd_parameters_present_flag) { + ret = hrd_parameters(gb, &vui->hrd_parameters); + if (ret < 0) + return ret; + } + vui->vcl_hrd_parameters_present_flag = get_bits(gb, 1); - if (vui->vcl_hrd_parameters_present_flag) - hrd_parameters(gb, &vui->hrd_parameters); + if (vui->vcl_hrd_parameters_present_flag) { + ret = hrd_parameters(gb, &vui->hrd_parameters); + if (ret < 0) + return ret; + } if (vui->nal_hrd_parameters_present_flag || vui->vcl_hrd_parameters_present_flag) vui->low_delay_hrd_flag = get_bits(gb, 1); vui->pic_struct_present_flag = get_bits(gb, 1); @@ -304,8 +316,11 @@ int ff_evc_parse_sps(GetBitContext *gb, EVCParamSets *ps) } sps->vui_parameters_present_flag = get_bits1(gb); - if (sps->vui_parameters_present_flag) - vui_parameters(gb, &(sps->vui_parameters)); + if (sps->vui_parameters_present_flag) { + ret = vui_parameters(gb, &(sps->vui_parameters)); + if (ret < 0) + goto fail; + } // @note // If necessary, add the missing fields to the EVCParserSPS structure