[PATCH] Use memmove instead of memcpy in fbblt.c when memory regions overlap.

[Adam Tkac]

Hello,

attached patch fixes wrong usage of memcpy. See
https://bugs.freedesktop.org/show_bug.cgi?id=36165 for more info.

Regards, Adam

>From b08e7198dc0141b8074d8fdff681019d86655a38 Mon Sep 17 00:00:00 2001
From: Adam Tkac <at...@redhat.com>
Date: Tue, 12 Apr 2011 16:49:43 +0200
Subject: [PATCH] Use memmove instead of memcpy in fbblt.c when memory regions
 overlap.

Signed-off-by: Adam Tkac <at...@redhat.com>
---
 fb/fb.h    |    4 ++++
 fb/fbblt.c |    4 ++--
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/fb/fb.h b/fb/fb.h
index eaa21ad..f68fe3b 100644
--- a/fb/fb.h
+++ b/fb/fb.h
@@ -66,6 +66,9 @@
     }                                                             \
 } while(0)
 
+/* XXX: Is this enough? */
+#define MEMMOVE_WRAPPED MEMCPY_WRAPPED
+
 #else
 
 #define FBPREFIX(x) fb##x
@@ -73,6 +76,7 @@
 #define READ(ptr) (*(ptr))
 #define MEMCPY_WRAPPED(dst, src, size) memcpy((dst), (src), (size))
 #define MEMSET_WRAPPED(dst, val, size) memset((dst), (val), (size))
+#define MEMMOVE_WRAPPED(dst, src, size) memmove((dst), (src), (size))
 
 #endif
 
diff --git a/fb/fbblt.c b/fb/fbblt.c
index a040298..e16c660 100644
--- a/fb/fbblt.c
+++ b/fb/fbblt.c
@@ -88,10 +88,10 @@ fbBlt (FbBits   *srcLine,
 
         if (!upsidedown)
             for (i = 0; i < height; i++)
-                MEMCPY_WRAPPED(dst + i * dstStride, src + i * srcStride, 
width);
+                MEMMOVE_WRAPPED(dst + i * dstStride, src + i * srcStride, 
width);
         else
             for (i = height - 1; i >= 0; i--)
-                MEMCPY_WRAPPED(dst + i * dstStride, src + i * srcStride, 
width);
+                MEMMOVE_WRAPPED(dst + i * dstStride, src + i * srcStride, 
width);
 
         return;
     }
-- 
1.7.4.4


_______________________________________________
xorg-devel@lists.x.org: X.Org development
Archives: http://lists.x.org/archives/xorg-devel
Info: http://lists.x.org/mailman/listinfo/xorg-devel