| Message ID | 20240801161814.7386-1-jamrial@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | [FFmpeg-devel] avcodec/cbs_h265: don't attempt to read 0 length elements in sei_3d_reference_displays_info | expand |
| Context | Check | Description |
|---|---|---|
| yinshiyou/make_loongarch64 | success | Make finished |
| yinshiyou/make_fate_loongarch64 | success | Make fate finished |
| andriy/make_x86 | success | Make finished |
| andriy/make_fate_x86 | success | Make fate finished |
On 8/1/2024 1:18 PM, James Almer wrote: > Fixes: 70458/clusterfuzz-testcase-minimized-ffmpeg_BSF_TRACE_HEADERS_fuzzer-5259339779080192 > Fixes: Assertion width > 0 && width <= 32 failed at libavcodec/cbs.c:608 > > Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > Signed-off-by: James Almer <jamrial@gmail.com> > --- > libavcodec/cbs_h265_syntax_template.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/libavcodec/cbs_h265_syntax_template.c b/libavcodec/cbs_h265_syntax_template.c > index f1be30a6c9..12fa185c77 100644 > --- a/libavcodec/cbs_h265_syntax_template.c > +++ b/libavcodec/cbs_h265_syntax_template.c > @@ -2307,7 +2307,10 @@ SEI_FUNC(sei_3d_reference_displays_info, (CodedBitstreamContext *ctx, RWContext > else > length = FFMAX(0, (int)current->exponent_ref_display_width[i] + > (int)current->prec_ref_display_width - 31); > - ubs(length, mantissa_ref_display_width[i], 1, i); > + if (length) > + ubs(length, mantissa_ref_display_width[i], 1, i); > + else > + infer(mantissa_ref_display_width[i], 0); > if (current->ref_viewing_distance_flag) { > us(6, exponent_ref_viewing_distance[i], 0, 62, 1, i); > if (!current->exponent_ref_viewing_distance[i]) > @@ -2315,7 +2318,10 @@ SEI_FUNC(sei_3d_reference_displays_info, (CodedBitstreamContext *ctx, RWContext > else > length = FFMAX(0, (int)current->exponent_ref_viewing_distance[i] + > (int)current->prec_ref_viewing_dist - 31); > - ubs(length, mantissa_ref_viewing_distance[i], 1, i); > + if (length) > + ubs(length, mantissa_ref_viewing_distance[i], 1, i); > + else > + infer(mantissa_ref_viewing_distance[i], 0); > } > flags(additional_shift_present_flag[i], 1, i); > if (current->additional_shift_present_flag[i]) Applied.
diff --git a/libavcodec/cbs_h265_syntax_template.c b/libavcodec/cbs_h265_syntax_template.c index f1be30a6c9..12fa185c77 100644 --- a/libavcodec/cbs_h265_syntax_template.c +++ b/libavcodec/cbs_h265_syntax_template.c @@ -2307,7 +2307,10 @@ SEI_FUNC(sei_3d_reference_displays_info, (CodedBitstreamContext *ctx, RWContext else length = FFMAX(0, (int)current->exponent_ref_display_width[i] + (int)current->prec_ref_display_width - 31); - ubs(length, mantissa_ref_display_width[i], 1, i); + if (length) + ubs(length, mantissa_ref_display_width[i], 1, i); + else + infer(mantissa_ref_display_width[i], 0); if (current->ref_viewing_distance_flag) { us(6, exponent_ref_viewing_distance[i], 0, 62, 1, i); if (!current->exponent_ref_viewing_distance[i]) @@ -2315,7 +2318,10 @@ SEI_FUNC(sei_3d_reference_displays_info, (CodedBitstreamContext *ctx, RWContext else length = FFMAX(0, (int)current->exponent_ref_viewing_distance[i] + (int)current->prec_ref_viewing_dist - 31); - ubs(length, mantissa_ref_viewing_distance[i], 1, i); + if (length) + ubs(length, mantissa_ref_viewing_distance[i], 1, i); + else + infer(mantissa_ref_viewing_distance[i], 0); } flags(additional_shift_present_flag[i], 1, i); if (current->additional_shift_present_flag[i])
Fixes: 70458/clusterfuzz-testcase-minimized-ffmpeg_BSF_TRACE_HEADERS_fuzzer-5259339779080192 Fixes: Assertion width > 0 && width <= 32 failed at libavcodec/cbs.c:608 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: James Almer <jamrial@gmail.com> --- libavcodec/cbs_h265_syntax_template.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)