[PATCH 5.18 42/67] dm verity: set DM_TARGET_IMMUTABLE feature flag

From: Greg Kroah-Hartman
Date: Fri Jun 03 2022 - 14:19:11 EST


From: Sarthak Kukreti <sarthakkukreti@xxxxxxxxxx>

commit 4caae58406f8ceb741603eee460d79bacca9b1b5 upstream.

The device-mapper framework provides a mechanism to mark targets as
immutable (and hence fail table reloads that try to change the target
type). Add the DM_TARGET_IMMUTABLE flag to the dm-verity target's
feature flags to prevent switching the verity target with a different
target type.

Fixes: a4ffc152198e ("dm: add verity target")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Sarthak Kukreti <sarthakkukreti@xxxxxxxxxx>
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/md/dm-verity-target.c | 1 +
1 file changed, 1 insertion(+)

--- a/drivers/md/dm-verity-target.c
+++ b/drivers/md/dm-verity-target.c
@@ -1312,6 +1312,7 @@ bad:

static struct target_type verity_target = {
.name = "verity",
+ .features = DM_TARGET_IMMUTABLE,
.version = {1, 8, 0},
.module = THIS_MODULE,
.ctr = verity_ctr,