PR #22268 opened by michaelni URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/22268 Patch URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/22268.patch
>From a0c63363fef06d46459f2c073b1ab3949a9e1d32 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer <[email protected]> Date: Sun, 22 Feb 2026 21:50:37 +0100 Subject: [PATCH 1/2] avcodec/hevc/ps: Factor window reading out Signed-off-by: Michael Niedermayer <[email protected]> --- libavcodec/hevc/ps.c | 49 ++++++++++++++++++++++++-------------------- libavcodec/hevc/ps.h | 5 +---- 2 files changed, 28 insertions(+), 26 deletions(-) diff --git a/libavcodec/hevc/ps.c b/libavcodec/hevc/ps.c index 46b38564d5..3606e9c29f 100644 --- a/libavcodec/hevc/ps.c +++ b/libavcodec/hevc/ps.c @@ -62,6 +62,22 @@ static const uint8_t hevc_sub_height_c[] = { 1, 2, 1, 1 }; +static int read_window(HEVCWindow *window, GetBitContext *gb, int chroma_format_idc, int w, int h) +{ + int64_t vert_mult = hevc_sub_height_c[chroma_format_idc]; + int64_t horiz_mult = hevc_sub_width_c [chroma_format_idc]; + int64_t left = get_ue_golomb_long(gb) * horiz_mult; + int64_t right = get_ue_golomb_long(gb) * horiz_mult; + int64_t top = get_ue_golomb_long(gb) * vert_mult; + int64_t bottom = get_ue_golomb_long(gb) * vert_mult; + + window->left_offset = left; + window->right_offset = right; + window->top_offset = top; + window->bottom_offset = bottom; + return 0; +} + static void remove_sps(HEVCParamSets *s, int id) { int i; @@ -702,12 +718,9 @@ static int decode_vps_ext(GetBitContext *gb, AVCodecContext *avctx, HEVCVPS *vps } if (get_bits1(gb) /* conformance_window_vps_flag */) { - int vert_mult = hevc_sub_height_c[vps->rep_format.chroma_format_idc]; - int horiz_mult = hevc_sub_width_c[vps->rep_format.chroma_format_idc]; - vps->rep_format.conf_win_left_offset = get_ue_golomb(gb) * horiz_mult; - vps->rep_format.conf_win_right_offset = get_ue_golomb(gb) * horiz_mult; - vps->rep_format.conf_win_top_offset = get_ue_golomb(gb) * vert_mult; - vps->rep_format.conf_win_bottom_offset = get_ue_golomb(gb) * vert_mult; + int ret = read_window(&vps->rep_format.conf_win, gb, vps->rep_format.chroma_format_idc, vps->rep_format.pic_width_in_luma_samples, vps->rep_format.pic_height_in_luma_samples); + if (ret < 0) + return ret; } vps->max_one_active_ref_layer = get_bits1(gb); @@ -962,12 +975,7 @@ static void decode_vui(GetBitContext *gb, AVCodecContext *avctx, vui->default_display_window_flag = get_bits1(gb); if (vui->default_display_window_flag) { - int vert_mult = hevc_sub_height_c[sps->chroma_format_idc]; - int horiz_mult = hevc_sub_width_c[sps->chroma_format_idc]; - vui->def_disp_win.left_offset = get_ue_golomb_long(gb) * horiz_mult; - vui->def_disp_win.right_offset = get_ue_golomb_long(gb) * horiz_mult; - vui->def_disp_win.top_offset = get_ue_golomb_long(gb) * vert_mult; - vui->def_disp_win.bottom_offset = get_ue_golomb_long(gb) * vert_mult; + read_window(&vui->def_disp_win, gb, sps->chroma_format_idc, sps->width, sps->height); if (apply_defdispwin && avctx->flags2 & AV_CODEC_FLAG2_IGNORE_CROP) { @@ -1281,10 +1289,10 @@ int ff_hevc_parse_sps(HEVCSPS *sps, GetBitContext *gb, unsigned int *sps_id, sps->width = rf->pic_width_in_luma_samples; sps->height = rf->pic_height_in_luma_samples; - sps->pic_conf_win.left_offset = rf->conf_win_left_offset; - sps->pic_conf_win.right_offset = rf->conf_win_right_offset; - sps->pic_conf_win.top_offset = rf->conf_win_top_offset; - sps->pic_conf_win.bottom_offset = rf->conf_win_bottom_offset; + sps->pic_conf_win.left_offset = rf->conf_win.left_offset; + sps->pic_conf_win.right_offset = rf->conf_win.right_offset; + sps->pic_conf_win.top_offset = rf->conf_win.top_offset; + sps->pic_conf_win.bottom_offset = rf->conf_win.bottom_offset; } else { sps->chroma_format_idc = get_ue_golomb_long(gb); @@ -1307,12 +1315,9 @@ int ff_hevc_parse_sps(HEVCSPS *sps, GetBitContext *gb, unsigned int *sps_id, sps->conformance_window = get_bits1(gb); if (sps->conformance_window) { - int vert_mult = hevc_sub_height_c[sps->chroma_format_idc]; - int horiz_mult = hevc_sub_width_c[sps->chroma_format_idc]; - sps->pic_conf_win.left_offset = get_ue_golomb_long(gb) * horiz_mult; - sps->pic_conf_win.right_offset = get_ue_golomb_long(gb) * horiz_mult; - sps->pic_conf_win.top_offset = get_ue_golomb_long(gb) * vert_mult; - sps->pic_conf_win.bottom_offset = get_ue_golomb_long(gb) * vert_mult; + ret = read_window(&sps->pic_conf_win, gb, sps->chroma_format_idc, sps->width, sps->height); + if (ret < 0) + return ret; if (avctx->flags2 & AV_CODEC_FLAG2_IGNORE_CROP) { av_log(avctx, AV_LOG_DEBUG, diff --git a/libavcodec/hevc/ps.h b/libavcodec/hevc/ps.h index d620887b8e..f5c5f81a6e 100644 --- a/libavcodec/hevc/ps.h +++ b/libavcodec/hevc/ps.h @@ -162,10 +162,7 @@ typedef struct RepFormat { uint8_t separate_colour_plane_flag; uint8_t bit_depth_luma; ///< bit_depth_vps_luma_minus8 + 8 uint8_t bit_depth_chroma; ///< bit_depth_vps_chroma_minus8 + 8 - uint16_t conf_win_left_offset; - uint16_t conf_win_right_offset; - uint16_t conf_win_top_offset; - uint16_t conf_win_bottom_offset; + HEVCWindow conf_win; } RepFormat; typedef struct HEVCVPS { -- 2.52.0 >From 50f997d32fbd6cc9a61121ca0c1991f270bcb79d Mon Sep 17 00:00:00 2001 From: Michael Niedermayer <[email protected]> Date: Sun, 22 Feb 2026 21:51:01 +0100 Subject: [PATCH 2/2] avcodec/hevc/ps: Check window parameters Fixes: signed integer overflow: -1094995529 * 2 cannot be represented in type 'int' Fixes: 484567435/clusterfuzz-testcase-minimized-ffmpeg_dem_HXVS_fuzzer-5628836988649472 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <[email protected]> --- libavcodec/hevc/ps.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/libavcodec/hevc/ps.c b/libavcodec/hevc/ps.c index 3606e9c29f..cc32043d12 100644 --- a/libavcodec/hevc/ps.c +++ b/libavcodec/hevc/ps.c @@ -71,6 +71,13 @@ static int read_window(HEVCWindow *window, GetBitContext *gb, int chroma_format_ int64_t top = get_ue_golomb_long(gb) * vert_mult; int64_t bottom = get_ue_golomb_long(gb) * vert_mult; + if (left < 0 || right < 0 || top < 0 || bottom < 0 || + w <= left + right || + h <= top + bottom) { + memset(window, 0, sizeof(*window)); + return AVERROR_INVALIDDATA; + } + window->left_offset = left; window->right_offset = right; window->top_offset = top; -- 2.52.0 _______________________________________________ ffmpeg-devel mailing list -- [email protected] To unsubscribe send an email to [email protected]
