dm verity: set DM_TARGET_IMMUTABLE feature flag

stable inclusion
from stable-4.19.246
commit 6bff6107d1364c95109609c3fd680e6c8d7fa503
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I5M4ZO


CVE: CVE-2022-2503

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

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: Luo Meng <luomeng12@huawei.com>

Conflicts:
	drivers/md/dm-verity-target.c
Reviewed-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Reviewed-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Yongqiang Liu <liuyongqiang13@huawei.com>