avcodec/cdgraphics: limit scrolling to the line

Fixes: out of array access Fixes: 47877/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_CDGRAPHICS_fuzzer-5690504626438144 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
2 years ago · b7e30a13d4
parent d8ee014254
commit b7e30a13d4
1 changed files with 1 additions and 1 deletions
--- a/libavcodec/cdgraphics.c
+++ b/libavcodec/cdgraphics.c
@ -240,7 +240,7 @@ static void cdg_scroll(CDGraphicsContext *cc, uint8_t *data,
    for (y = FFMAX(0, vinc); y < FFMIN(CDG_FULL_HEIGHT + vinc, CDG_FULL_HEIGHT); y++)
        memcpy(out + FFMAX(0, hinc) + stride * y,
               in + FFMAX(0, hinc) - hinc + (y - vinc) * stride,
-               FFMIN(stride + hinc, stride));
+               FFABS(stride) - FFABS(hinc));

    if (vinc > 0)
        cdg_fill_wrapper(0, 0, out,