diff mbox series

[RFC,v13,12/20] dm verity: set DM_TARGET_SINGLETON feature flag

Message ID 1709168102-7677-13-git-send-email-wufan@linux.microsoft.com
State New
Headers
Series Integrity Policy Enforcement LSM (IPE) |

Commit Message

Fan Wu Feb. 29, 2024, 12:54 a.m. UTC 
  The device-mapper has a flag to mark targets as singleton, which is a
required flag for immutable targets. Without this flag, multiple
dm-verity targets can be added to a mapped device, which has no
practical use cases. Also from dm_table_get_immutable_target(),
it documented that "Immutable target is implicitly a singleton".

This patch adds the missing flag, restricting only one
dm-verity target per mapped device.

Signed-off-by: Fan Wu <wufan@linux.microsoft.com>

---
v1-v10:
  + Not present

v11:
  + Introduced

v12:
  + No changes

v13:
  + No changes
---
 drivers/md/dm-verity-target.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Mike Snitzer March 2, 2024, 4:01 p.m. UTC | #1 
On Wed, Feb 28 2024 at  7:54P -0500,
Fan Wu <wufan@linux.microsoft.com> wrote:

> The device-mapper has a flag to mark targets as singleton, which is a
> required flag for immutable targets. Without this flag, multiple
> dm-verity targets can be added to a mapped device, which has no
> practical use cases. Also from dm_table_get_immutable_target(),
> it documented that "Immutable target is implicitly a singleton".
> 
> This patch adds the missing flag, restricting only one
> dm-verity target per mapped device.
> 
> Signed-off-by: Fan Wu <wufan@linux.microsoft.com>

FYI, I have picked this one up and staged it in dm-6.9 and linux-next:
https://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm.git/commit/?h=dm-6.9&id=9356fcfe0ac4a8545f9fc32f2e404524e1115ee6

Mike
diff mbox series

Patch

diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c
index 1b591bfa90d5..a99ef30e45ca 100644
--- a/drivers/md/dm-verity-target.c
+++ b/drivers/md/dm-verity-target.c
@@ -1559,7 +1559,7 @@  int dm_verity_get_root_digest(struct dm_target *ti, u8 **root_digest, unsigned i
 
 static struct target_type verity_target = {
 	.name		= "verity",
-	.features	= DM_TARGET_IMMUTABLE,
+	.features	= DM_TARGET_SINGLETON | DM_TARGET_IMMUTABLE,
 	.version	= {1, 10, 0},
 	.module		= THIS_MODULE,
 	.ctr		= verity_ctr,