user/xorg-server: Update for GCC 12+ compat

1 files changed, 70 insertions, 0 deletions

diff --git a/user/xorg-server/rgb-mask.patch b/user/xorg-server/rgb-mask.patch
new file mode 100644
index 000000000..a503a6e16
--- /dev/null
+++ b/user/xorg-server/rgb-mask.patch
@@ -0,0 +1,70 @@
+From 7e142cb2a848acb6af986fa91d254d4c23963b24 Mon Sep 17 00:00:00 2001
+From: luporl <luporl@FreeBSD.org>
+Date: Wed, 9 Dec 2020 11:11:15 -0300
+Subject: [PATCH] xserver: fix RGB mask handling
+
+On FreeBSD 13.0-CURRENT for PowerPC64 big-endian (BE), X was
+crashing in some cases. For instance, when twm was started
+and the background was clicked to open its menu, X crashed
+with a segmentation fault, trying to dereference a null pointer
+at CreatePicture().
+
+There were 2 issues with xorg-server handling of RGB masks that
+caused the pointer above to be null and thus the crash:
+- wrong use of ffs() to get the RGB offsets from the masks
+- overflow when shifting a 16-bit integer
+
+This change fixes both issues. They happen when the system is BE
+but has a video adapter using a little-endian (LE) ARGB32
+framebuffer. In order to display the correct colors, this setup
+requires a BE RGBA32 color format to be used by X, by setting
+the RGB masks appropriately, that didn't work properly because of
+the issues above.
+---
+ hw/xfree86/common/xf86Helper.c |  6 +++---
+ render/picture.c               | 12 ++++++------
+ 2 files changed, 9 insertions(+), 9 deletions(-)
+
+diff --git a/hw/xfree86/common/xf86Helper.c b/hw/xfree86/common/xf86Helper.c
+index 31aa068e0e..16ab309e27 100644
+--- a/hw/xfree86/common/xf86Helper.c
++++ b/hw/xfree86/common/xf86Helper.c
+@@ -729,9 +729,9 @@ xf86SetWeight(ScrnInfoPtr scrp, rgb weight, rgb mask)
+         scrp->mask.red = mask.red;
+         scrp->mask.green = mask.green;
+         scrp->mask.blue = mask.blue;
+-        scrp->offset.red = ffs(mask.red);
+-        scrp->offset.green = ffs(mask.green);
+-        scrp->offset.blue = ffs(mask.blue);
++        scrp->offset.red = ffs(mask.red) - 1;
++        scrp->offset.green = ffs(mask.green) - 1;
++        scrp->offset.blue = ffs(mask.blue) - 1;
+     }
+     return TRUE;
+ }
+diff --git a/render/picture.c b/render/picture.c
+index 876316dc1c..afa0d258fa 100644
+--- a/render/picture.c
++++ b/render/picture.c
+@@ -523,12 +523,12 @@ PictureMatchVisual(ScreenPtr pScreen, int depth, VisualPtr pVisual)
+                     return format;
+             }
+             else {
+-                if (format->direct.redMask << format->direct.red ==
+-                    pVisual->redMask &&
+-                    format->direct.greenMask << format->direct.green ==
+-                    pVisual->greenMask &&
+-                    format->direct.blueMask << format->direct.blue ==
+-                    pVisual->blueMask) {
++                if ((unsigned long)format->direct.redMask <<
++                        format->direct.red == pVisual->redMask &&
++                    (unsigned long)format->direct.greenMask <<
++                        format->direct.green == pVisual->greenMask &&
++                    (unsigned long)format->direct.blueMask <<
++                        format->direct.blue == pVisual->blueMask) {
+                     return format;
+                 }
+             }
+-- 
+GitLab
+