security, keys: convert key.usage from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c
index 6bbe2f5..0f06215 100644
--- a/security/keys/request_key_auth.c
+++ b/security/keys/request_key_auth.c
@@ -213,7 +213,7 @@ struct key *request_key_auth_new(struct key *target, const void *callout_info,
if (ret < 0)
goto error_inst;
- kleave(" = {%d,%d}", authkey->serial, atomic_read(&authkey->usage));
+ kleave(" = {%d,%d}", authkey->serial, refcount_read(&authkey->usage));
return authkey;
auth_key_revoked: