Browse Source

avcodec/mpeg4videodec: Check sprite delta upshift against overflowing.

Fixes: runtime error: signed integer overflow: -268386304 * 16 cannot be represented in type 'int'
Fixes: 2204/clusterfuzz-testcase-minimized-5616756909408256

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
tags/n3.4
Michael Niedermayer 8 years ago
parent
commit
12245ab1f6
1 changed files with 10 additions and 8 deletions
  1. +10
    -8
      libavcodec/mpeg4videodec.c

+ 10
- 8
libavcodec/mpeg4videodec.c View File

@@ -361,14 +361,16 @@ static int mpeg4_decode_sprite_trajectory(Mpeg4DecContext *ctx, GetBitContext *g
int shift_y = 16 - ctx->sprite_shift[0];
int shift_c = 16 - ctx->sprite_shift[1];

if (shift_c < 0 || shift_y < 0 ||
FFABS(sprite_offset[0][0]) >= INT_MAX >> shift_y ||
FFABS(sprite_offset[1][0]) >= INT_MAX >> shift_c ||
FFABS(sprite_offset[0][1]) >= INT_MAX >> shift_y ||
FFABS(sprite_offset[1][1]) >= INT_MAX >> shift_c
) {
avpriv_request_sample(s->avctx, "Too large sprite shift or offset");
goto overflow;
for (i = 0; i < 2; i++) {
if (shift_c < 0 || shift_y < 0 ||
FFABS( sprite_offset[0][i]) >= INT_MAX >> shift_y ||
FFABS( sprite_offset[1][i]) >= INT_MAX >> shift_c ||
FFABS(s->sprite_delta[0][i]) >= INT_MAX >> shift_y ||
FFABS(s->sprite_delta[1][i]) >= INT_MAX >> shift_y
) {
avpriv_request_sample(s->avctx, "Too large sprite shift, delta or offset");
goto overflow;
}
}

for (i = 0; i < 2; i++) {


Loading…
Cancel
Save