This is a note to let you know that I've just added the patch titled
misc: mic: Fix for double fetch security bug in VOP driver
to my char-misc git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
in the char-misc-linus branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.
If you have any questions about this process, please let me know.
>From 82dc4afd7e65455464f0fc2fe6976efde54fe451 Mon Sep 17 00:00:00 2001
From: Ashutosh Dixit <ashutosh.dixit@xxxxxxxxx>
Date: Wed, 27 Apr 2016 14:36:05 -0700
Subject: misc: mic: Fix for double fetch security bug in VOP driver
The MIC VOP driver does two successive reads from user space to read a
variable length data structure. Kernel memory corruption can result if
the data structure changes between the two reads. This patch disallows
the chance of this happening.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=116651
Reported by: Pengfei Wang <wpengfeinudt@xxxxxxxxx>
Reviewed-by: Sudeep Dutt <sudeep.dutt@xxxxxxxxx>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@xxxxxxxxx>
Cc: stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/misc/mic/vop/vop_vringh.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/drivers/misc/mic/vop/vop_vringh.c b/drivers/misc/mic/vop/vop_vringh.c
index e94c7fb6712a..88e45234d527 100644
--- a/drivers/misc/mic/vop/vop_vringh.c
+++ b/drivers/misc/mic/vop/vop_vringh.c
@@ -945,6 +945,11 @@ static long vop_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
ret = -EFAULT;
goto free_ret;
}
+ /* Ensure desc has not changed between the two reads */
+ if (memcmp(&dd, dd_config, sizeof(dd))) {
+ ret = -EINVAL;
+ goto free_ret;
+ }
mutex_lock(&vdev->vdev_mutex);
mutex_lock(&vi->vop_mutex);
ret = vop_virtio_add_device(vdev, dd_config);
--
2.8.0
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html