dm verity: set DM_TARGET_IMMUTABLE feature flag

stable inclusion
from stable-v5.10.120
commit 8df42bcd364cc3b41105215d841792aea787b133
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5L6BR

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=8df42bcd364cc3b41105215d841792aea787b133



--------------------------------

commit 4caae584 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: a4ffc152 ("dm: add verity target")
Cc: stable@vger.kernel.org
Signed-off-by: Sarthak Kukreti <sarthakkukreti@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>

 Conflicts:
	drivers/md/dm-verity-target.c
Reviewed-by: Luo Meng <luomeng12@huawei.com>
Acked-by: Xie XiuQi <xiexiuqi@huawei.com>