[FFmpeg-cvslog] swscale/output: Fix integer overflow in yuv2rgb_write_full() with out of range input

[Michael Niedermayer]

ffmpeg | branch: release/2.8 | Michael Niedermayer <michael at niedermayer.cc> | Sun Feb 16 20:11:52 2020 +0100| [4359dddb72b2bfd241573d0506a5def20d7c9a81] | committer: Michael Niedermayer

swscale/output: Fix integer overflow in yuv2rgb_write_full() with out of range input

Fixes: signed integer overflow: 1169365504 + 981452800 cannot be represented in type 'int'
Fixes: ticket8293

Found-by: Suhwan
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit e057e83a4ff4c0eeeb78dffe58e21af951c056b6)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=4359dddb72b2bfd241573d0506a5def20d7c9a81
---

 libswscale/output.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/libswscale/output.c b/libswscale/output.c
index 581758b667..50eb7c3fee 100644
--- a/libswscale/output.c
+++ b/libswscale/output.c
@@ -1531,9 +1531,9 @@ static av_always_inline void yuv2rgb_write_full(SwsContext *c,
     Y -= c->yuv2rgb_y_offset;
     Y *= c->yuv2rgb_y_coeff;
     Y += 1 << 21;
-    R = Y + V*c->yuv2rgb_v2r_coeff;
-    G = Y + V*c->yuv2rgb_v2g_coeff + U*c->yuv2rgb_u2g_coeff;
-    B = Y +                          U*c->yuv2rgb_u2b_coeff;
+    R = (unsigned)Y + V*c->yuv2rgb_v2r_coeff;
+    G = (unsigned)Y + V*c->yuv2rgb_v2g_coeff + U*c->yuv2rgb_u2g_coeff;
+    B = (unsigned)Y +                          U*c->yuv2rgb_u2b_coeff;
     if ((R | G | B) & 0xC0000000) {
         R = av_clip_uintp2(R, 30);
         G = av_clip_uintp2(G, 30);