We check end of screen before writing the pixel but before that
complement color also accesses screen pixel so we have to check before
that. This fixes a segmentation fault with guest_hwcursor when pointer
is partially out of screen at lower right corner.

Signed-off-by: BALATON Zoltan <[email protected]>
---
 hw/display/ati.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/hw/display/ati.c b/hw/display/ati.c
index 7543065456..9fb798b3e9 100644
--- a/hw/display/ati.c
+++ b/hw/display/ati.c
@@ -216,6 +216,9 @@ static void ati_cursor_draw_line(VGACommonState *vga, 
uint8_t *d, int scr_y)
         uint8_t abits = vga_read_byte(vga, srcoff + i);
         uint8_t xbits = vga_read_byte(vga, srcoff + i + 8);
         for (j = 0; j < 8; j++, abits <<= 1, xbits <<= 1, idx++) {
+            if (vga->hw_cursor_x + idx >= h) {
+                return; /* end of screen, don't span to next line */
+            }
             if (abits & BIT(7)) {
                 if (xbits & BIT(7)) {
                     color = dp[idx] ^ 0xffffffff; /* complement */
@@ -226,9 +229,6 @@ static void ati_cursor_draw_line(VGACommonState *vga, 
uint8_t *d, int scr_y)
                 color = (xbits & BIT(7) ? s->regs.cur_color1 :
                                           s->regs.cur_color0) | 0xff000000;
             }
-            if (vga->hw_cursor_x + idx >= h) {
-                return; /* end of screen, don't span to next line */
-            }
             dp[idx] = color;
         }
     }
-- 
2.41.3


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