fixed propfonts bug which was related to illegal memory accesing of lcd_bitmap function called by lcd_clearrect.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@1158 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 11 insertions, 2 deletions

diff --git a/firmware/drivers/lcd.c b/firmware/drivers/lcd.c
index e502c0c6b4..a228a6501b 100644
--- a/firmware/drivers/lcd.c
+++ b/firmware/drivers/lcd.c
@@ -644,10 +644,19 @@ void lcd_bitmap (unsigned char *src, int x, int y, int nx, int ny,
                  bool clear)
 {
     unsigned char *dst;
-    unsigned char *dst2 = &display[x][y/8];
+    unsigned char *dst2;
     unsigned int data, mask, mask2, mask3, mask4;
-    int shift = y & 7;
+    int shift;
 
+    if (((unsigned)x >= LCD_WIDTH) || ((unsigned)y >= LCD_HEIGHT))
+        return;
+    if (((unsigned)(x + nx)) >= LCD_WIDTH)
+       nx = LCD_WIDTH - x;
+    if (((unsigned)(y + ny)) >= LCD_HEIGHT)
+        ny = LCD_HEIGHT - y;      
+
+    shift = y & 2;
+    dst2 = &display[x][y/8];
     ny += shift;
 
     /* Calculate bit masks */