diff options
| author | Dan Rosenberg <drosenberg@vsecurity.com> | 2010-09-22 13:05:09 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-09-26 17:21:27 -0700 |
| commit | e286d83959320fcf7eadfc81aeceb6e1a81667c9 (patch) | |
| tree | db2c29cfc3bf967966ccf91bd09b1352fe0b60c8 | |
| parent | 0a71220bc6dc9ef745de3beb618f18c42af433db (diff) | |
drivers/video/sis/sis_main.c: prevent reading uninitialized stack memory
commit fd02db9de73faebc51240619c7c7f99bee9f65c7 upstream.
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>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | drivers/video/sis/sis_main.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/video/sis/sis_main.c b/drivers/video/sis/sis_main.c index a4e05e4d7501..e1836d7140a8 100644 --- a/drivers/video/sis/sis_main.c +++ b/drivers/video/sis/sis_main.c @@ -1701,6 +1701,9 @@ static int sisfb_ioctl(struct fb_info *info, unsigned int cmd, break; case FBIOGET_VBLANK: + + memset(&sisvbblank, 0, sizeof(struct fb_vblank)); + sisvbblank.count = 0; sisvbblank.flags = sisfb_setupvbblankflags(ivideo, &sisvbblank.vcount, &sisvbblank.hcount); |