[PATCH] mi: Integer overflow for dashed lines longer than 46340. #31093

Siddhesh Poyarekar siddhesh.poyarekar at gmail.com
Sun Oct 24 23:21:46 PDT 2010


Lines of length greater than 46340 can be drawn with one of the
coordinates being negative. However for dashed lines, miPolyBuildPoly
overflows the int type when setting up edges for a section of the
dashed line. This results in the dashed segments not being drawn at
all.

Signed-off-by: Siddhesh Poyarekar <siddhesh.poyarekar at gmail.com>
---
 mi/miwideline.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/mi/miwideline.c b/mi/miwideline.c
index b11b40b..8a1567e 100644
--- a/mi/miwideline.c
+++ b/mi/miwideline.c
@@ -403,7 +403,7 @@ miPolyBuildPoly (
     i = top;
     j = StepAround (top, -1, count);
 
-    if (slopes[j].dy * slopes[i].dx > slopes[i].dy * slopes[j].dx)
+    if ((long long)slopes[j].dy * slopes[i].dx > (long long)slopes[i].dy * slopes[j].dx)
     {
 	clockwise = -1;
 	slopeoff = -1;
-- 
1.7.2.3



More information about the xorg-devel mailing list