diff options
| author | Herbert Xu <herbert@gondor.apana.org.au> | 2025-05-28 13:18:17 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2025-06-11 11:57:14 -0700 |
| commit | 488ef3560196ee10fc1c5547e1574a87068c3494 (patch) | |
| tree | 7ea1bcd3ffe3aa051adcdd0946b014fb8a22647a | |
| parent | aef17cb3d3c43854002956f24c24ec8e1a0e3546 (diff) | |
KEYS: Invert FINAL_PUT bit
Invert the FINAL_PUT bit so that test_bit_acquire and clear_bit_unlock
can be used instead of smp_mb.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | include/linux/key.h | 2 | ||||
| -rw-r--r-- | security/keys/gc.c | 4 | ||||
| -rw-r--r-- | security/keys/key.c | 5 |
3 files changed, 6 insertions, 5 deletions
diff --git a/include/linux/key.h b/include/linux/key.h index ba05de8579ec..81b8f05c6898 100644 --- a/include/linux/key.h +++ b/include/linux/key.h @@ -236,7 +236,7 @@ struct key { #define KEY_FLAG_ROOT_CAN_INVAL 7 /* set if key can be invalidated by root without permission */ #define KEY_FLAG_KEEP 8 /* set if key should not be removed */ #define KEY_FLAG_UID_KEYRING 9 /* set if key is a user or user session keyring */ -#define KEY_FLAG_FINAL_PUT 10 /* set if final put has happened on key */ +#define KEY_FLAG_USER_ALIVE 10 /* set if final put has not happened on key yet */ /* the key type and key description string * - the desc is used to match a key against search criteria diff --git a/security/keys/gc.c b/security/keys/gc.c index f27223ea4578..748e83818a76 100644 --- a/security/keys/gc.c +++ b/security/keys/gc.c @@ -218,8 +218,8 @@ continue_scanning: key = rb_entry(cursor, struct key, serial_node); cursor = rb_next(cursor); - if (test_bit(KEY_FLAG_FINAL_PUT, &key->flags)) { - smp_mb(); /* Clobber key->user after FINAL_PUT seen. */ + if (!test_bit_acquire(KEY_FLAG_USER_ALIVE, &key->flags)) { + /* Clobber key->user after final put seen. */ goto found_unreferenced_key; } diff --git a/security/keys/key.c b/security/keys/key.c index 7198cd2ac3a3..3bbdde778631 100644 --- a/security/keys/key.c +++ b/security/keys/key.c @@ -298,6 +298,7 @@ struct key *key_alloc(struct key_type *type, const char *desc, key->restrict_link = restrict_link; key->last_used_at = ktime_get_real_seconds(); + key->flags |= 1 << KEY_FLAG_USER_ALIVE; if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) key->flags |= 1 << KEY_FLAG_IN_QUOTA; if (flags & KEY_ALLOC_BUILT_IN) @@ -658,8 +659,8 @@ void key_put(struct key *key) key->user->qnbytes -= key->quotalen; spin_unlock_irqrestore(&key->user->lock, flags); } - smp_mb(); /* key->user before FINAL_PUT set. */ - set_bit(KEY_FLAG_FINAL_PUT, &key->flags); + /* Mark key as safe for GC after key->user done. */ + clear_bit_unlock(KEY_FLAG_USER_ALIVE, &key->flags); schedule_work(&key_gc_work); } } |