diff --git a/include/linux/key.h b/include/linux/key.h
index bfc014c..5253471 100644
--- a/include/linux/key.h
+++ b/include/linux/key.h
@@ -271,7 +271,7 @@
 
 extern struct key *key_lookup(key_serial_t id);
 
-static inline key_serial_t key_serial(struct key *key)
+static inline key_serial_t key_serial(const struct key *key)
 {
 	return key ? key->serial : 0;
 }
diff --git a/lib/mpi/mpicoder.c b/lib/mpi/mpicoder.c
index fe84bb9..716802b 100644
--- a/lib/mpi/mpicoder.c
+++ b/lib/mpi/mpicoder.c
@@ -255,6 +255,8 @@
 	if (!n)
 		n++;		/* avoid zero length allocation */
 	p = buffer = kmalloc(n, GFP_KERNEL);
+	if (!p)
+		return NULL;
 
 	for (i = a->nlimbs - 1; i >= 0; i--) {
 		alimb = a->d[i];
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index d661afb..d45061d 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -99,6 +99,7 @@
 			    struct inode *inode, enum ima_hooks func, int mask)
 {
 	struct task_struct *tsk = current;
+	const struct cred *cred = current_cred();
 	int i;
 
 	if ((rule->flags & IMA_FUNC) && rule->func != func)
@@ -108,7 +109,7 @@
 	if ((rule->flags & IMA_FSMAGIC)
 	    && rule->fsmagic != inode->i_sb->s_magic)
 		return false;
-	if ((rule->flags & IMA_UID) && rule->uid != tsk->cred->uid)
+	if ((rule->flags & IMA_UID) && rule->uid != cred->uid)
 		return false;
 	for (i = 0; i < MAX_LSM_RULES; i++) {
 		int rc = 0;
diff --git a/security/keys/user_defined.c b/security/keys/user_defined.c
index 69ff52c..2aee3c5 100644
--- a/security/keys/user_defined.c
+++ b/security/keys/user_defined.c
@@ -59,7 +59,7 @@
 	/* attach the data */
 	upayload->datalen = datalen;
 	memcpy(upayload->data, data, datalen);
-	rcu_assign_pointer(key->payload.data, upayload);
+	rcu_assign_keypointer(key, upayload);
 	ret = 0;
 
 error:
@@ -98,7 +98,7 @@
 	if (ret == 0) {
 		/* attach the new data, displacing the old */
 		zap = key->payload.data;
-		rcu_assign_pointer(key->payload.data, upayload);
+		rcu_assign_keypointer(key, upayload);
 		key->expiry = 0;
 	}
 
@@ -133,7 +133,7 @@
 	key_payload_reserve(key, 0);
 
 	if (upayload) {
-		rcu_assign_pointer(key->payload.data, NULL);
+		rcu_assign_keypointer(key, NULL);
 		kfree_rcu(upayload, rcu);
 	}
 }