heap-buffer-overflow libde265/libde265/motion.cc:1860 in derive_spatial_luma_vector_prediction

[fdu-sec]

Description

heap-buffer-overflow libde265/libde265/motion.cc:1860 in derive_spatial_luma_vector_prediction(base_context*, de265_image*, slice_segment_header const*, int, int, int, int, int, int, int, int, int, int, unsigned char*, MotionVector*)

Version

 dec265  v1.0.14
-----------------
usage: dec265 [options] videofile.bin
The video file must be a raw bitstream, or a stream with NAL units (option -n).

options:
  -q, --quiet       do not show decoded image
  -t, --threads N   set number of worker threads (0 - no threading)
  -c, --check-hash  perform hash check
  -n, --nal         input is a stream with 4-byte length prefixed NAL units
  -f, --frames N    set number of frames to process
  -o, --output      write YUV reconstruction
  -d, --dump        dump headers
  -0, --noaccel     do not use any accelerated code (SSE)
  -v, --verbose     increase verbosity level (up to 3 times)
  -L, --no-logging  disable logging
  -B, --write-bytestream FILENAME  write raw bytestream (from NAL input)
  -m, --measure YUV compute PSNRs relative to reference YUV
  -T, --highest-TID select highest temporal sublayer to decode
      --disable-deblocking   disable deblocking filter
      --disable-sao          disable sample-adaptive offset filter
  -h, --help        show help

Replay

cd libde265
CC="gcc -fsanitize=address" CXX="g++ -fsanitize=address" ./configure
make -j

# You need to try running poc several times to see the asan result.
./dec265/dec265 ./poc

ASAN

==1982966==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x61b000001b10 at pc 0x56501e786954 bp 0x7ffc66164680 sp 0x7ffc66164670
READ of size 4 at 0x61b000001b10 thread T0
    #0 0x56501e786953 in derive_spatial_luma_vector_prediction(base_context*, de265_image*, slice_segment_header const*, int, int, int, int, int, int, int, int, int, int, unsigned char*, MotionVector*) libde265/libde265/motion.cc:1860
    #1 0x56501e787950 in fill_luma_motion_vector_predictors(base_context*, slice_segment_header const*, de265_image*, int, int, int, int, int, int, int, int, int, int, MotionVector*) libde265/libde265/motion.cc:1990
    #2 0x56501e79c58a in luma_motion_vector_prediction(base_context*, slice_segment_header const*, de265_image*, PBMotionCoding const&, int, int, int, int, int, int, int, int, int, int) libde265/libde265/motion.cc:2063
    #3 0x56501e79c58a in motion_vectors_and_ref_indices(base_context*, slice_segment_header const*, de265_image*, PBMotionCoding const&, int, int, int, int, int, int, int, int, PBMotion*) libde265/libde265/motion.cc:2155
    #4 0x56501e79c58a in decode_prediction_unit(base_context*, slice_segment_header const*, de265_image*, PBMotionCoding const&, int, int, int, int, int, int, int, int) libde265/libde265/motion.cc:2195
    #5 0x56501e662806 in read_prediction_unit(thread_context*, int, int, int, int, int, int, int, int, int) libde265/libde265/slice.cc:4145
    #6 0x56501e66c4cb in read_coding_unit(thread_context*, int, int, int, int) libde265/libde265/slice.cc:4506
    #7 0x56501e670f59 in read_coding_quadtree(thread_context*, int, int, int, int) libde265/libde265/slice.cc:4650
    #8 0x56501e670df6 in read_coding_quadtree(thread_context*, int, int, int, int) libde265/libde265/slice.cc:4644
    #9 0x56501e670f59 in read_coding_quadtree(thread_context*, int, int, int, int) libde265/libde265/slice.cc:4650
    #10 0x56501e673696 in decode_substream(thread_context*, bool, bool) libde265/libde265/slice.cc:4750
    #11 0x56501e679fc9 in read_slice_segment_data(thread_context*) libde265/libde265/slice.cc:5063
    #12 0x56501e53c8b4 in decoder_context::decode_slice_unit_sequential(image_unit*, slice_unit*) libde265/libde265/decctx.cc:854
    #13 0x56501e543e55 in decoder_context::decode_slice_unit_parallel(image_unit*, slice_unit*) libde265/libde265/decctx.cc:956
    #14 0x56501e5477eb in decoder_context::decode_some(bool*) libde265/libde265/decctx.cc:741
    #15 0x56501e55957a in decoder_context::read_slice_NAL(bitreader&, NAL_unit*, nal_header&) libde265/libde265/decctx.cc:699
    #16 0x56501e55b645 in decoder_context::decode_NAL(NAL_unit*) libde265/libde265/decctx.cc:1241
    #17 0x56501e55c508 in decoder_context::decode(int*) libde265/libde265/decctx.cc:1329
    #18 0x56501e51646c in main libde265/dec265/dec265.cc:784
    #19 0x7fd4aa229d8f in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58
    #20 0x7fd4aa229e3f in __libc_start_main_impl ../csu/libc-start.c:392
    #21 0x56501e518ce4 in _start (eva/asan-bin/NestFuzz/libde265/dec265+0x1ece4)

0x61b000001b10 is located 8 bytes to the right of 1416-byte region [0x61b000001580,0x61b000001b08)
allocated by thread T0 here:
    #0 0x7fd4aaab61e7 in operator new(unsigned long) ../../../../src/libsanitizer/asan/asan_new_delete.cpp:99
    #1 0x56501e557f17 in decoder_context::read_slice_NAL(bitreader&, NAL_unit*, nal_header&) libde265/libde265/decctx.cc:635

SUMMARY: AddressSanitizer: heap-buffer-overflow libde265/libde265/motion.cc:1860 in derive_spatial_luma_vector_prediction(base_context*, de265_image*, slice_segment_header const*, int, int, int, int, int, int, int, int, int, int, unsigned char*, MotionVector*)

POC

poc

Environment

Description:	Ubuntu 22.04.2 LTS
gcc (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0

Credit

Yuchuan Meng (Fudan University)

[farindk]

I could not reproduce the POC even with many runs of dec265.
However, the above commit could be a potential fix.
Please confirm whether this fixes it.

[fdu-sec]

Yes. the above commit may be fix it.
You can reproduce this issue at commit 7065a53.

[carnil]

CVE-2023-49465 is assigned for this issue.