+ drivers-video-sis-sis_mainc-prevent-reading-uninitialized-stack-memory.patch added to -mm tree

+ drivers-video-sis-sis_mainc-prevent-reading-uninitialized-stack-memory.patch added to -mm tree

[akpm]

The patch titled
     drivers/video/sis/sis_main.c: prevent reading uninitialized stack memory
has been added to the -mm tree.  Its filename is
     drivers-video-sis-sis_mainc-prevent-reading-uninitialized-stack-memory.patch

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------------------------------------------------------
Subject: drivers/video/sis/sis_main.c: prevent reading uninitialized stack memory
From: Dan Rosenberg <drosenberg@vsecurity.com>

The FBIOGET_VBLANK device ioctl allows unprivileged users to read 16 bytes
of uninitialized stack memory, because the "reserved" member of the
fb_vblank struct declared on the stack is not altered or zeroed before
being copied back to the user.  This patch takes care of it.

Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com>
Cc: Thomas Winischhofer <thomas@winischhofer.net>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 drivers/video/sis/sis_main.c |    3 +++
 1 file changed, 3 insertions(+)

diff -puN drivers/video/sis/sis_main.c~drivers-video-sis-sis_mainc-prevent-reading-uninitialized-stack-memory drivers/video/sis/sis_main.c
--- a/drivers/video/sis/sis_main.c~drivers-video-sis-sis_mainc-prevent-reading-uninitialized-stack-memory
+++ a/drivers/video/sis/sis_main.c
@@ -1701,6 +1701,9 @@ static int	sisfb_ioctl(struct fb_info *i
 		break;
 
 	   case FBIOGET_VBLANK:
+
+		memset(&sisvbblank, 0, sizeof(struct fb_vblank));
+
 		sisvbblank.count = 0;
 		sisvbblank.flags = sisfb_setupvbblankflags(ivideo, &sisvbblank.vcount, &sisvbblank.hcount);
 
_

Patches currently in -mm which might be from drosenberg@vsecurity.com are

linux-next.patch
drivers-serial-serial_corec-prevent-reading-uninitialized-stack-memory.patch
drivers-video-sis-sis_mainc-prevent-reading-uninitialized-stack-memory.patch
drivers-char-amiserialc-prevent-reading-uninitialized-stack-memory.patch
drivers-char-nozomic-prevent-reading-uninitialized-stack-memory.patch