Merge tag 'keys-request-20190626' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull request_key improvements from David Howells:
 "These are all request_key()-related, including a fix and some improvements:

   - Fix the lack of a Link permission check on a key found by
     request_key(), thereby enabling request_key() to link keys that
     don't grant this permission to the target keyring (which must still
     grant Write permission).

     Note that the key must be in the caller's keyrings already to be
     found.

   - Invalidate used request_key authentication keys rather than
     revoking them, so that they get cleaned up immediately rather than
     hanging around till the expiry time is passed.

   - Move the RCU locks outwards from the keyring search functions so
     that a request_key_rcu() can be provided. This can be called in RCU
     mode, so it can't sleep and can't upcall - but it can be called
     from LOOKUP_RCU pathwalk mode.

   - Cache the latest positive result of request_key*() temporarily in
     task_struct so that filesystems that make a lot of request_key()
     calls during pathwalk can take advantage of it to avoid having to
     redo the searching. This requires CONFIG_KEYS_REQUEST_CACHE=y.

     It is assumed that the key just found is likely to be used multiple
     times in each step in an RCU pathwalk, and is likely to be reused
     for the next step too.

     Note that the cleanup of the cache is done on TIF_NOTIFY_RESUME,
     just before userspace resumes, and on exit"

* tag 'keys-request-20190626' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  keys: Kill off request_key_async{,_with_auxdata}
  keys: Cache result of request_key*() temporarily in task_struct
  keys: Provide request_key_rcu()
  keys: Move the RCU locks outwards from the keyring search functions
  keys: Invalidate used request_key authentication keys
  keys: Fix request_key() lack of Link perm check on found key

1 files changed, 3 insertions, 3 deletions

diff --git a/security/keys/internal.h b/security/keys/internal.h
index 0f48b53754b3..663f291e30d4 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -135,11 +135,11 @@ struct keyring_search_context {
 
 extern bool key_default_cmp(const struct key *key,
 			    const struct key_match_data *match_data);
-extern key_ref_t keyring_search_aux(key_ref_t keyring_ref,
+extern key_ref_t keyring_search_rcu(key_ref_t keyring_ref,
 				    struct keyring_search_context *ctx);
 
-extern key_ref_t search_my_process_keyrings(struct keyring_search_context *ctx);
-extern key_ref_t search_process_keyrings(struct keyring_search_context *ctx);
+extern key_ref_t search_cred_keyrings_rcu(struct keyring_search_context *ctx);
+extern key_ref_t search_process_keyrings_rcu(struct keyring_search_context *ctx);
 
 extern struct key *find_keyring_by_name(const char *name, bool uid_keyring);