[FFmpeg-cvslog] lavfi/tests: Fix 16-bit vf_blend test to avoid memory not aligned to 2 bytes

[Andrey Semashev]

ffmpeg | branch: master | Andrey Semashev <andrey.semashev at gmail.com> | Thu May 24 00:07:36 2018 +0300| [d7eb8d84757155c1fb0fe1a8269025e22e9bf0ec] | committer: Michael Niedermayer

lavfi/tests: Fix 16-bit vf_blend test to avoid memory not aligned to 2 bytes

Generic C implementation of vf_blend performs reads and writes of 16-bit
elements, which requires the buffers to be aligned to at least 2-byte
boundary.

Also, the change fixes source buffer overrun caused by src_offset being
added to to test handling of misaligned buffers.

Fixes: #7226

Reviewed-by: Paul B Mahol <onemda at gmail.com>
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=d7eb8d84757155c1fb0fe1a8269025e22e9bf0ec
---

 tests/checkasm/vf_blend.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/checkasm/vf_blend.c b/tests/checkasm/vf_blend.c
index 912f3a2c38..a7578fec39 100644
--- a/tests/checkasm/vf_blend.c
+++ b/tests/checkasm/vf_blend.c
@@ -71,7 +71,7 @@
         w = WIDTH / depth;                                                                 \
                                                                                            \
         for (i = 0; i < BUF_UNITS - 1; i++) {                                              \
-            int src_offset = i * SIZE_PER_UNIT + i; /* Test various alignments */          \
+            int src_offset = i * SIZE_PER_UNIT + (BUF_UNITS - 1 - i) * depth; /* Test various alignments */  \
             int dst_offset = i * SIZE_PER_UNIT; /* dst must be aligned */                  \
             randomize_buffers();                                                           \
             call_ref(top1 + src_offset, w, bot1 + src_offset, w,                           \