avcodec/g2meet: Change order of operations to avoid undefined behavior

Fixes: signed integer overflow: 65280 * 196032 cannot be represented in type 'int'
Fixes: 7279/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_G2M_fuzzer-5977332473921536

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2018-05-04 18:16:08 +02:00
parent 8d1263fa19
commit 0a47451458

View File

@ -1356,14 +1356,16 @@ static void g2m_paint_cursor(G2MContext *c, uint8_t *dst, int stride)
} else {
dst += x * 3;
}
if (y < 0) {
if (y < 0)
h += y;
if (w < 0 || h < 0)
return;
if (y < 0) {
cursor += -y * c->cursor_stride;
} else {
dst += y * stride;
}
if (w < 0 || h < 0)
return;
for (j = 0; j < h; j++) {
for (i = 0; i < w; i++) {