diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-05-28 11:45:41 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-05-28 11:45:41 -0700 |
| commit | 43a1e3744548e6fd85873e6fb43e293eb4010694 (patch) | |
| tree | 1718e70a9e68a7b3a3ba412f238df2365ffa6cb8 | |
| parent | eb3f4b7426cfd2b79d65b7d37155480b32259a11 (diff) | |
security/keys: fix missed RCU read section on lookup
Nicholas Carlini reports that the keyring code calls assoc_array_find()
in find_key_to_update() without holding the RCU read lock, while the
assoc_array_gc() code really is designed around removing the node from
the tree and then freeing it after an RCU grace-period.
The regular key handling doesn't see this because holding the keyring
semaphore hides any lifetime issues, but the persistent key handling
uses a different model.
Instead of extending the keyring locking, just do the simple RCU locking
that the assoc_array was designed for.
Reported-by: Nicholas Carlini <npc@anthropic.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Paul Moore <paul@paul-moore.com>
Cc: James Morris James Morris <jmorris@namei.org>
Cc: Serge E. Hallyn <serge@hallyn.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | security/keys/keyring.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/security/keys/keyring.c b/security/keys/keyring.c index b39038f7dd31..5a9887d6b7be 100644 --- a/security/keys/keyring.c +++ b/security/keys/keyring.c @@ -1109,6 +1109,7 @@ key_ref_t find_key_to_update(key_ref_t keyring_ref, kenter("{%d},{%s,%s}", keyring->serial, index_key->type->name, index_key->description); + guard(rcu)(); object = assoc_array_find(&keyring->keys, &keyring_assoc_array_ops, index_key); |