lisa/android_kernel_xiaomi_sm8350
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

dm ioctl: prevent potential spectre v1 gadget

Browse Source 
[ Upstream commit cd9c88da171a62c4b0f1c70e50c75845969fbc18 ]

It appears like cmd could be a Spectre v1 gadget as it's supplied by a
user and used as an array index. Prevent the contents of kernel memory
from being leaked to userspace via speculative execution by using
array_index_nospec.

Signed-off-by: Jordy Zomer <jordy@pwning.systems>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Jordy Zomer 2022-01-29 15:58:39 +01:00 committed by Greg Kroah-Hartman
parent 73dd98ac19
commit 0320bac580
1 changed files with 2 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/md/dm-ioctl.c
View File

@ -17,6 +17,7 @@
#include <linux/dm-ioctl.h>
#include <linux/hdreg.h>
#include <linux/compat.h>
#include <linux/nospec.h>
#include <linux/uaccess.h>
@ -1696,6 +1697,7 @@ static ioctl_fn lookup_ioctl(unsigned int cmd, int *ioctl_flags)
if (unlikely(cmd >= ARRAY_SIZE(_ioctls)))
return NULL;
cmd = array_index_nospec(cmd, ARRAY_SIZE(_ioctls));
*ioctl_flags = _ioctls[cmd].flags;
return _ioctls[cmd].fn;
}