[FFmpeg-cvslog] avcodec/bink: Avoid undefined out of array end pointers in binkb_decode_plane()

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Wed Jan 11 20:50:39 2023 +0100| [ea9deafd3b13233802c4548c4c58a707d76805a3] | committer: Michael Niedermayer

avcodec/bink: Avoid undefined out of array end pointers in binkb_decode_plane()

Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=ea9deafd3b13233802c4548c4c58a707d76805a3
---

 libavcodec/bink.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/libavcodec/bink.c b/libavcodec/bink.c
index a3140114f0..15fc9d29ed 100644
--- a/libavcodec/bink.c
+++ b/libavcodec/bink.c
@@ -870,7 +870,7 @@ static int binkb_decode_plane(BinkContext *c, AVFrame *frame, GetBitContext *gb,
 
     binkb_init_bundles(c);
     ref_start = frame->data[plane_idx];
-    ref_end   = frame->data[plane_idx] + (bh * frame->linesize[plane_idx] + bw - 1) * 8;
+    ref_end   = frame->data[plane_idx] + ((bh - 1) * frame->linesize[plane_idx] + bw - 1) * 8;
 
     for (i = 0; i < 64; i++)
         coordmap[i] = (i & 7) + (i >> 3) * stride;
@@ -926,7 +926,7 @@ static int binkb_decode_plane(BinkContext *c, AVFrame *frame, GetBitContext *gb,
                 xoff = binkb_get_value(c, BINKB_SRC_X_OFF);
                 yoff = binkb_get_value(c, BINKB_SRC_Y_OFF) + ybias;
                 ref = dst + xoff + yoff * stride;
-                if (ref < ref_start || ref + 8*stride > ref_end) {
+                if (ref < ref_start || ref > ref_end) {
                     av_log(c->avctx, AV_LOG_WARNING, "Reference block is out of bounds\n");
                 } else if (ref + 8*stride < dst || ref >= dst + 8*stride) {
                     c->put_pixels_tab(dst, ref, stride, 8);
@@ -942,7 +942,7 @@ static int binkb_decode_plane(BinkContext *c, AVFrame *frame, GetBitContext *gb,
                 xoff = binkb_get_value(c, BINKB_SRC_X_OFF);
                 yoff = binkb_get_value(c, BINKB_SRC_Y_OFF) + ybias;
                 ref = dst + xoff + yoff * stride;
-                if (ref < ref_start || ref + 8 * stride > ref_end) {
+                if (ref < ref_start || ref > ref_end) {
                     av_log(c->avctx, AV_LOG_WARNING, "Reference block is out of bounds\n");
                 } else if (ref + 8*stride < dst || ref >= dst + 8*stride) {
                     c->put_pixels_tab(dst, ref, stride, 8);
@@ -974,7 +974,7 @@ static int binkb_decode_plane(BinkContext *c, AVFrame *frame, GetBitContext *gb,
                 xoff = binkb_get_value(c, BINKB_SRC_X_OFF);
                 yoff = binkb_get_value(c, BINKB_SRC_Y_OFF) + ybias;
                 ref = dst + xoff + yoff * stride;
-                if (ref < ref_start || ref + 8 * stride > ref_end) {
+                if (ref < ref_start || ref > ref_end) {
                     av_log(c->avctx, AV_LOG_WARNING, "Reference block is out of bounds\n");
                 } else if (ref + 8*stride < dst || ref >= dst + 8*stride) {
                     c->put_pixels_tab(dst, ref, stride, 8);