avcodec/vmnc: Check that rectangles are within the picture
authorMichael Niedermayer <michaelni@gmx.at>
Mon, 20 Jan 2014 17:08:18 +0000 (18:08 +0100)
committerMichael Niedermayer <michaelni@gmx.at>
Fri, 21 Mar 2014 03:23:59 +0000 (04:23 +0100)
Prevents out of array accesses with CODEC_FLAG_EMU_EDGE

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit 6ba02602aa7fc7d38db582e75b8b093fb3c1608d)

Conflicts:

libavcodec/vmnc.c

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit 7c17207ab9acfaa934e8feb8fba90765c9d0b989)

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
libavcodec/vmnc.c

index 7655103..ecde81c 100644 (file)
@@ -275,6 +275,11 @@ static int decode_hextile(VmncContext *c, uint8_t* dst, const uint8_t* src, int
                     }
                     xy = *src++;
                     wh = *src++;
+                    if (   (xy >> 4) + (wh >> 4) + 1 > w - i
+                        || (xy & 0xF) + (wh & 0xF)+1 > h - j) {
+                        av_log(c->avctx, AV_LOG_ERROR, "Rectangle outside picture\n");
+                        return AVERROR_INVALIDDATA;
+                    }
                     paint_rect(dst2, xy >> 4, xy & 0xF, (wh>>4)+1, (wh & 0xF)+1, fg, bpp, stride);
                 }
             }