diff options
| author | Jordy Zomer <jordy@jordyzomer.github.io> | 2022-01-29 15:58:39 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-04-15 14:18:33 +0200 |
| commit | 0320bac5801b31407200227173205d017488f140 (patch) | |
| tree | 605a15adb550d7dccc85f81efe77c4906cfe1941 /drivers/md | |
| parent | 73dd98ac192d9116e7966e068a4368057df2ea55 (diff) | |
dm ioctl: prevent potential spectre v1 gadget
[ 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>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/dm-ioctl.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c index 3f15d8dc2b71..7a73f2fa0ad7 100644 --- a/drivers/md/dm-ioctl.c +++ b/drivers/md/dm-ioctl.c @@ -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; } |