1
0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-28 20:53:54 +02:00

swscale/output: alpha can become negative after scaling, use multiply

Fixes: left shift of negative value -3245
Fixes: 69047/clusterfuzz-testcase-minimized-ffmpeg_SWS_fuzzer-6571511551950848

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 9e6c5b6e86)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2024-06-16 01:51:22 +02:00
parent a40d0a3832
commit bd43ebe43b
No known key found for this signature in database
GPG Key ID: B18E8928B3948D64

View File

@ -1162,8 +1162,8 @@ yuv2rgba64_1_c_template(SwsContext *c, const int32_t *buf0,
Y2 += (1 << 13) - (1 << 29);
if (hasAlpha) {
A1 = abuf0[i * 2 ] << 11;
A2 = abuf0[i * 2 + 1] << 11;
A1 = abuf0[i * 2 ] * (1 << 11);
A2 = abuf0[i * 2 + 1] * (1 << 11);
A1 += 1 << 13;
A2 += 1 << 13;
@ -1208,8 +1208,8 @@ yuv2rgba64_1_c_template(SwsContext *c, const int32_t *buf0,
Y2 += (1 << 13) - (1 << 29);
if (hasAlpha) {
A1 = abuf0[i * 2 ] << 11;
A2 = abuf0[i * 2 + 1] << 11;
A1 = abuf0[i * 2 ] * (1 << 11);
A2 = abuf0[i * 2 + 1] * (1 << 11);
A1 += 1 << 13;
A2 += 1 << 13;
@ -1377,7 +1377,7 @@ yuv2rgba64_full_1_c_template(SwsContext *c, const int32_t *buf0,
Y += (1 << 13) - (1 << 29);
if (hasAlpha) {
A = abuf0[i] << 11;
A = abuf0[i] * (1 << 11);
A += 1 << 13;
}
@ -1410,7 +1410,7 @@ yuv2rgba64_full_1_c_template(SwsContext *c, const int32_t *buf0,
Y += (1 << 13) - (1 << 29);
if (hasAlpha) {
A = abuf0[i] << 11;
A = abuf0[i] * (1 << 11);
A += 1 << 13;
}