write in 30M

hc

2024-02-20 ea08eeccae9297f7aabd2ef7f0c2517ac4549acc

 kernel/net/l2tp/l2tp_ppp.c
..
..
@@ -651,6 +651,65 @@
651
651
 	return mtu - PPPOL2TP_HEADER_OVERHEAD;
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 }
653
653
 
654
+static struct l2tp_tunnel *pppol2tp_tunnel_get(struct net *net,
655
+					       const struct l2tp_connect_info *info,
656
+					       bool *new_tunnel)
657
+{
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+	struct l2tp_tunnel *tunnel;
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+	int error;
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+
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+	*new_tunnel = false;
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+
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+	tunnel = l2tp_tunnel_get(net, info->tunnel_id);
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+
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+	/* Special case: create tunnel context if session_id and
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+	 * peer_session_id is 0. Otherwise look up tunnel using supplied
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+	 * tunnel id.
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+	 */
669
+	if (!info->session_id && !info->peer_session_id) {
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+		if (!tunnel) {
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+			struct l2tp_tunnel_cfg tcfg = {
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+				.encap = L2TP_ENCAPTYPE_UDP,
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+			};
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+
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+			/* Prevent l2tp_tunnel_register() from trying to set up
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+			 * a kernel socket.
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+			 */
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+			if (info->fd < 0)
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+				return ERR_PTR(-EBADF);
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+
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+			error = l2tp_tunnel_create(info->fd,
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+						   info->version,
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+						   info->tunnel_id,
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+						   info->peer_tunnel_id, &tcfg,
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+						   &tunnel);
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+			if (error < 0)
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+				return ERR_PTR(error);
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+
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+			l2tp_tunnel_inc_refcount(tunnel);
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+			error = l2tp_tunnel_register(tunnel, net, &tcfg);
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+			if (error < 0) {
692
+				kfree(tunnel);
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+				return ERR_PTR(error);
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+			}
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+
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+			*new_tunnel = true;
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+		}
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+	} else {
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+		/* Error if we can't find the tunnel */
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+		if (!tunnel)
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+			return ERR_PTR(-ENOENT);
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+
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+		/* Error if socket is not prepped */
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+		if (!tunnel->sock) {
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+			l2tp_tunnel_dec_refcount(tunnel);
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+			return ERR_PTR(-ENOENT);
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+		}
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+	}
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+
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+	return tunnel;
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+}
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+
654
713
 /* connect() handler. Attach a PPPoX socket to a tunnel UDP socket
655
714
  */
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715
 static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr,
..
..
@@ -664,7 +723,6 @@
664
723
 	struct pppol2tp_session *ps;
665
724
 	struct l2tp_session_cfg cfg = { 0, };
666
725
 	bool drop_refcnt = false;
667
-	bool drop_tunnel = false;
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726
 	bool new_session = false;
669
727
 	bool new_tunnel = false;
670
728
 	int error;
..
..
@@ -672,6 +730,14 @@
672
730
 	error = pppol2tp_sockaddr_get_info(uservaddr, sockaddr_len, &info);
673
731
 	if (error < 0)
674
732
 		return error;
733
+
734
+	/* Don't bind if tunnel_id is 0 */
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+	if (!info.tunnel_id)
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+		return -EINVAL;
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+
738
+	tunnel = pppol2tp_tunnel_get(sock_net(sk), &info, &new_tunnel);
739
+	if (IS_ERR(tunnel))
740
+		return PTR_ERR(tunnel);
675
741
 
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742
 	lock_sock(sk);
677
743
 
..
..
@@ -684,62 +750,6 @@
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 	error = -EALREADY;
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751
 	if (sk->sk_user_data)
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752
 		goto end; /* socket is already attached */
687
-
688
-	/* Don't bind if tunnel_id is 0 */
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-	error = -EINVAL;
690
-	if (!info.tunnel_id)
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-		goto end;
692
-
693
-	tunnel = l2tp_tunnel_get(sock_net(sk), info.tunnel_id);
694
-	if (tunnel)
695
-		drop_tunnel = true;
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-
697
-	/* Special case: create tunnel context if session_id and
698
-	 * peer_session_id is 0. Otherwise look up tunnel using supplied
699
-	 * tunnel id.
700
-	 */
701
-	if (!info.session_id && !info.peer_session_id) {
702
-		if (!tunnel) {
703
-			struct l2tp_tunnel_cfg tcfg = {
704
-				.encap = L2TP_ENCAPTYPE_UDP,
705
-			};
706
-
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-			/* Prevent l2tp_tunnel_register() from trying to set up
708
-			 * a kernel socket.
709
-			 */
710
-			if (info.fd < 0) {
711
-				error = -EBADF;
712
-				goto end;
713
-			}
714
-
715
-			error = l2tp_tunnel_create(info.fd,
716
-						   info.version,
717
-						   info.tunnel_id,
718
-						   info.peer_tunnel_id, &tcfg,
719
-						   &tunnel);
720
-			if (error < 0)
721
-				goto end;
722
-
723
-			l2tp_tunnel_inc_refcount(tunnel);
724
-			error = l2tp_tunnel_register(tunnel, sock_net(sk),
725
-						     &tcfg);
726
-			if (error < 0) {
727
-				kfree(tunnel);
728
-				goto end;
729
-			}
730
-			drop_tunnel = true;
731
-			new_tunnel = true;
732
-		}
733
-	} else {
734
-		/* Error if we can't find the tunnel */
735
-		error = -ENOENT;
736
-		if (!tunnel)
737
-			goto end;
738
-
739
-		/* Error if socket is not prepped */
740
-		if (!tunnel->sock)
741
-			goto end;
742
-	}
743
753
 
744
754
 	if (tunnel->peer_tunnel_id == 0)
745
755
 		tunnel->peer_tunnel_id = info.peer_tunnel_id;
..
..
@@ -841,8 +851,7 @@
841
851
 	}
842
852
 	if (drop_refcnt)
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853
 		l2tp_session_dec_refcount(session);
844
-	if (drop_tunnel)
845
-		l2tp_tunnel_dec_refcount(tunnel);
854
+	l2tp_tunnel_dec_refcount(tunnel);
846
855
 	release_sock(sk);
847
856
 
848
857
 	return error;