X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=security%2Fkeys%2Fuser_defined.c;h=e9aa079296561507835e0e349a55f07b11bec5bb;hb=7d32c0aca4fbd0319c860d12af5fae3e88c760e6;hp=7c687d568221cd71a3e863b9c9c50f5cd9352005;hpb=cd354f1ae75e6466a7e31b727faede57a1f89ca5;p=firefly-linux-kernel-4.4.55.git

diff --git a/security/keys/user_defined.c b/security/keys/user_defined.c
index 7c687d568221..e9aa07929656 100644
--- a/security/keys/user_defined.c
+++ b/security/keys/user_defined.c
@@ -199,7 +199,8 @@ long user_read(const struct key *key, char __user *buffer, size_t buflen)
 	struct user_key_payload *upayload;
 	long ret;
 
-	upayload = rcu_dereference(key->payload.data);
+	upayload = rcu_dereference_protected(
+		key->payload.data, rwsem_is_locked(&((struct key *)key)->sem));
 	ret = upayload->datalen;
 
 	/* we can return the data as is */