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| author | Jordy Zomer <jordy@jordyzomer.github.io> | 2022-01-29 15:58:39 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-04-15 14:15:02 +0200 |
| commit | 7ae2c5b89da3cfaf856df880af27d3bb32a74b3d (patch) | |
| tree | 44c1a67aa5df39bdc621975c4cc51ede35281911 | |
| parent | 75517bd7e4afad5a800b4d14f80aa7e6f73a9681 (diff) | |
| download | linux-stable-7ae2c5b89da3cfaf856df880af27d3bb32a74b3d.tar.gz linux-stable-7ae2c5b89da3cfaf856df880af27d3bb32a74b3d.tar.bz2 linux-stable-7ae2c5b89da3cfaf856df880af27d3bb32a74b3d.zip | |
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>
| -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 17cbad58834f..0aae4a46db66 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> @@ -1670,6 +1671,7 @@ 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; } |