Update Linux to v5.4.148

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.4.148.tar.gz

Change-Id: Ib3d26c5ba9b022e2e03533005c4fed4d7c30b61b
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/kernel/audit.c b/kernel/audit.c
index da8dc0d..05ae208 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -879,7 +879,7 @@
 	return 0;
 }
 
-int audit_send_list(void *_dest)
+int audit_send_list_thread(void *_dest)
 {
 	struct audit_netlink_list *dest = _dest;
 	struct sk_buff *skb;
@@ -923,19 +923,30 @@
 	return NULL;
 }
 
+static void audit_free_reply(struct audit_reply *reply)
+{
+	if (!reply)
+		return;
+
+	if (reply->skb)
+		kfree_skb(reply->skb);
+	if (reply->net)
+		put_net(reply->net);
+	kfree(reply);
+}
+
 static int audit_send_reply_thread(void *arg)
 {
 	struct audit_reply *reply = (struct audit_reply *)arg;
-	struct sock *sk = audit_get_sk(reply->net);
 
 	audit_ctl_lock();
 	audit_ctl_unlock();
 
 	/* Ignore failure. It'll only happen if the sender goes away,
 	   because our timeout is set to infinite. */
-	netlink_unicast(sk, reply->skb, reply->portid, 0);
-	put_net(reply->net);
-	kfree(reply);
+	netlink_unicast(audit_get_sk(reply->net), reply->skb, reply->portid, 0);
+	reply->skb = NULL;
+	audit_free_reply(reply);
 	return 0;
 }
 
@@ -949,35 +960,32 @@
  * @payload: payload data
  * @size: payload size
  *
- * Allocates an skb, builds the netlink message, and sends it to the port id.
- * No failure notifications.
+ * Allocates a skb, builds the netlink message, and sends it to the port id.
  */
 static void audit_send_reply(struct sk_buff *request_skb, int seq, int type, int done,
 			     int multi, const void *payload, int size)
 {
-	struct net *net = sock_net(NETLINK_CB(request_skb).sk);
-	struct sk_buff *skb;
 	struct task_struct *tsk;
-	struct audit_reply *reply = kmalloc(sizeof(struct audit_reply),
-					    GFP_KERNEL);
+	struct audit_reply *reply;
 
+	reply = kzalloc(sizeof(*reply), GFP_KERNEL);
 	if (!reply)
 		return;
 
-	skb = audit_make_reply(seq, type, done, multi, payload, size);
-	if (!skb)
-		goto out;
-
-	reply->net = get_net(net);
+	reply->skb = audit_make_reply(seq, type, done, multi, payload, size);
+	if (!reply->skb)
+		goto err;
+	reply->net = get_net(sock_net(NETLINK_CB(request_skb).sk));
 	reply->portid = NETLINK_CB(request_skb).portid;
-	reply->skb = skb;
 
 	tsk = kthread_run(audit_send_reply_thread, reply, "audit_send_reply");
-	if (!IS_ERR(tsk))
-		return;
-	kfree_skb(skb);
-out:
-	kfree(reply);
+	if (IS_ERR(tsk))
+		goto err;
+
+	return;
+
+err:
+	audit_free_reply(reply);
 }
 
 /*
@@ -1100,13 +1108,11 @@
 	audit_log_end(ab);
 }
 
-static int audit_set_feature(struct sk_buff *skb)
+static int audit_set_feature(struct audit_features *uaf)
 {
-	struct audit_features *uaf;
 	int i;
 
 	BUILD_BUG_ON(AUDIT_LAST_FEATURE + 1 > ARRAY_SIZE(audit_feature_names));
-	uaf = nlmsg_data(nlmsg_hdr(skb));
 
 	/* if there is ever a version 2 we should handle that here */
 
@@ -1174,6 +1180,7 @@
 {
 	u32			seq;
 	void			*data;
+	int			data_len;
 	int			err;
 	struct audit_buffer	*ab;
 	u16			msg_type = nlh->nlmsg_type;
@@ -1187,6 +1194,7 @@
 
 	seq  = nlh->nlmsg_seq;
 	data = nlmsg_data(nlh);
+	data_len = nlmsg_len(nlh);
 
 	switch (msg_type) {
 	case AUDIT_GET: {
@@ -1210,7 +1218,7 @@
 		struct audit_status	s;
 		memset(&s, 0, sizeof(s));
 		/* guard against past and future API changes */
-		memcpy(&s, data, min_t(size_t, sizeof(s), nlmsg_len(nlh)));
+		memcpy(&s, data, min_t(size_t, sizeof(s), data_len));
 		if (s.mask & AUDIT_STATUS_ENABLED) {
 			err = audit_set_enabled(s.enabled);
 			if (err < 0)
@@ -1314,7 +1322,9 @@
 			return err;
 		break;
 	case AUDIT_SET_FEATURE:
-		err = audit_set_feature(skb);
+		if (data_len < sizeof(struct audit_features))
+			return -EINVAL;
+		err = audit_set_feature(data);
 		if (err)
 			return err;
 		break;
@@ -1323,9 +1333,14 @@
 	case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
 		if (!audit_enabled && msg_type != AUDIT_USER_AVC)
 			return 0;
+		/* exit early if there isn't at least one character to print */
+		if (data_len < 2)
+			return -EINVAL;
 
 		err = audit_filter(msg_type, AUDIT_FILTER_USER);
 		if (err == 1) { /* match or error */
+			char *str = data;
+
 			err = 0;
 			if (msg_type == AUDIT_USER_TTY) {
 				err = tty_audit_push();
@@ -1333,26 +1348,24 @@
 					break;
 			}
 			audit_log_user_recv_msg(&ab, msg_type);
-			if (msg_type != AUDIT_USER_TTY)
+			if (msg_type != AUDIT_USER_TTY) {
+				/* ensure NULL termination */
+				str[data_len - 1] = '\0';
 				audit_log_format(ab, " msg='%.*s'",
 						 AUDIT_MESSAGE_TEXT_MAX,
-						 (char *)data);
-			else {
-				int size;
-
+						 str);
+			} else {
 				audit_log_format(ab, " data=");
-				size = nlmsg_len(nlh);
-				if (size > 0 &&
-				    ((unsigned char *)data)[size - 1] == '\0')
-					size--;
-				audit_log_n_untrustedstring(ab, data, size);
+				if (data_len > 0 && str[data_len - 1] == '\0')
+					data_len--;
+				audit_log_n_untrustedstring(ab, str, data_len);
 			}
 			audit_log_end(ab);
 		}
 		break;
 	case AUDIT_ADD_RULE:
 	case AUDIT_DEL_RULE:
-		if (nlmsg_len(nlh) < sizeof(struct audit_rule_data))
+		if (data_len < sizeof(struct audit_rule_data))
 			return -EINVAL;
 		if (audit_enabled == AUDIT_LOCKED) {
 			audit_log_common_recv_msg(audit_context(), &ab,
@@ -1364,7 +1377,7 @@
 			audit_log_end(ab);
 			return -EPERM;
 		}
-		err = audit_rule_change(msg_type, seq, data, nlmsg_len(nlh));
+		err = audit_rule_change(msg_type, seq, data, data_len);
 		break;
 	case AUDIT_LIST_RULES:
 		err = audit_list_rules_send(skb, seq);
@@ -1379,7 +1392,7 @@
 	case AUDIT_MAKE_EQUIV: {
 		void *bufp = data;
 		u32 sizes[2];
-		size_t msglen = nlmsg_len(nlh);
+		size_t msglen = data_len;
 		char *old, *new;
 
 		err = -EINVAL;
@@ -1455,7 +1468,7 @@
 
 		memset(&s, 0, sizeof(s));
 		/* guard against past and future API changes */
-		memcpy(&s, data, min_t(size_t, sizeof(s), nlmsg_len(nlh)));
+		memcpy(&s, data, min_t(size_t, sizeof(s), data_len));
 		/* check if new data is valid */
 		if ((s.enabled != 0 && s.enabled != 1) ||
 		    (s.log_passwd != 0 && s.log_passwd != 1))