drbd: don't leak the shared secret to unprivileged netlink dumps

The conversion to explicit netlink serialization dropped the
exclude_sensitive parameter from net_conf_to_skb(), so each caller has
to sanitize by hand. Two dump paths were missed:
drbd_nl_get_connections_dumpit() and the volume-less connection branch
of get_one_status(). Neither op carries GENL_ADMIN_PERM, so any
unprivileged local user could read the CRAM-HMAC secret.

Add a net_conf_to_skb_sanitized() wrapper and route all three callers
through it.

Fixes: 8098eeb693 ("drbd: replace genl_magic with explicit netlink serialization")
Reported-by: Vivek Parikh <vivek.parikh@breachx.ai>
Signed-off-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Link: https://patch.msgid.link/20260814151617.73752-1-christoph.boehmwalder@linbit.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Böhmwalder 2026-08-14 17:16:17 +02:00 • committed by Jens Axboe
commit c71bf113df