Patchset for CVE-2020-1749 Kernel 4.19

["Schmid, Carsten" <Carsten_Schmid@mentor.com>]

[-- Attachment #1: Type: text/plain, Size: 416 bytes --]

Hi Greg,

as announced i have backported the identified patches for CVE-2020-1749 from kernel 5.x into v4.19.
Applies to stable linux-v4.19.y (with y=114).

Please find the patches for 4.19 appended.

Best regards
Carsten
-----------------
Mentor Graphics (Deutschland) GmbH, Arnulfstraße 201, 80634 München / Germany
Registergericht München HRB 106955, Geschäftsführer: Thomas Heurung, Alexander Walter

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: 0001-ipv6-Move-ipv6-stubs-to-a-separate-header-file.patch --]
[-- Type: text/x-patch; name="0001-ipv6-Move-ipv6-stubs-to-a-separate-header-file.patch", Size: 10756 bytes --]

From 81132cc6d1b45795570da7adbdf41d58c025a009 Mon Sep 17 00:00:00 2001
From: David Ahern <dsahern@gmail.com>
Date: Fri, 22 Mar 2019 06:06:09 -0700
Subject: [PATCH 1/3] ipv6: Move ipv6 stubs to a separate header file

[ Upstream commit 3616d08bcbb564c7765187cd45ad392e49bad73a ]

Fixes CVE-2020-1749
Backported from v5.2-rc1
Patch 1/3

The number of stubs is growing and has nothing to do with addrconf.
Move the definition of the stubs to a separate header file and update
users. In the move, drop the vxlan specific comment before ipv6_stub.

Code move only; no functional change intended.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Carsten Schmid <carsten_schmid@mentor.com>
---
 drivers/infiniband/core/addr.c                |  2 +-
 .../net/ethernet/mellanox/mlx5/core/en_tc.c   |  1 +
 drivers/net/geneve.c                          |  1 +
 drivers/net/usb/cdc_mbim.c                    |  1 +
 drivers/net/vxlan.c                           |  1 +
 include/net/addrconf.h                        | 41 -------------
 include/net/ipv6_stubs.h                      | 58 +++++++++++++++++++
 include/net/udp_tunnel.h                      |  2 +-
 net/bridge/br_arp_nd_proxy.c                  |  1 +
 net/core/filter.c                             |  1 +
 net/core/lwt_bpf.c                            |  1 +
 net/ipv6/addrconf_core.c                      |  2 +-
 net/ipv6/af_inet6.c                           |  1 +
 net/mpls/af_mpls.c                            |  2 +-
 net/tipc/udp_media.c                          |  2 +-
 15 files changed, 71 insertions(+), 46 deletions(-)
 create mode 100644 include/net/ipv6_stubs.h

diff --git a/drivers/infiniband/core/addr.c b/drivers/infiniband/core/addr.c
index 6e96a2fb97dc..327ca9ff8127 100644
--- a/drivers/infiniband/core/addr.c
+++ b/drivers/infiniband/core/addr.c
@@ -42,7 +42,7 @@
 #include <net/neighbour.h>
 #include <net/route.h>
 #include <net/netevent.h>
-#include <net/addrconf.h>
+#include <net/ipv6_stubs.h>
 #include <net/ip6_route.h>
 #include <rdma/ib_addr.h>
 #include <rdma/ib.h>
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
index c8928ce69185..f1c26742572b 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
@@ -46,6 +46,7 @@
 #include <net/tc_act/tc_csum.h>
 #include <net/vxlan.h>
 #include <net/arp.h>
+#include <net/ipv6_stubs.h>
 #include "en.h"
 #include "en_rep.h"
 #include "en_tc.h"
diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index ff83408733d4..d808442f98ca 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -14,6 +14,7 @@
 #include <linux/module.h>
 #include <linux/etherdevice.h>
 #include <linux/hash.h>
+#include <net/ipv6_stubs.h>
 #include <net/dst_metadata.h>
 #include <net/gro_cells.h>
 #include <net/rtnetlink.h>
diff --git a/drivers/net/usb/cdc_mbim.c b/drivers/net/usb/cdc_mbim.c
index 0362acd5cdca..28321aca48fe 100644
--- a/drivers/net/usb/cdc_mbim.c
+++ b/drivers/net/usb/cdc_mbim.c
@@ -23,6 +23,7 @@
 #include <linux/usb/cdc_ncm.h>
 #include <net/ipv6.h>
 #include <net/addrconf.h>
+#include <net/ipv6_stubs.h>
 
 /* alternative VLAN for IP session 0 if not untagged */
 #define MBIM_IPS0_VID	4094
diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 64751b089482..eae6723ae5ea 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -20,6 +20,7 @@
 #include <linux/ethtool.h>
 #include <net/arp.h>
 #include <net/ndisc.h>
+#include <net/ipv6_stubs.h>
 #include <net/ip.h>
 #include <net/icmp.h>
 #include <net/rtnetlink.h>
diff --git a/include/net/addrconf.h b/include/net/addrconf.h
index 6def0351bcc3..7ea893b0ec0f 100644
--- a/include/net/addrconf.h
+++ b/include/net/addrconf.h
@@ -227,47 +227,6 @@ bool ipv6_chk_mcast_addr(struct net_device *dev, const struct in6_addr *group,
 
 void ipv6_mc_dad_complete(struct inet6_dev *idev);
 
-/* A stub used by vxlan module. This is ugly, ideally these
- * symbols should be built into the core kernel.
- */
-struct ipv6_stub {
-	int (*ipv6_sock_mc_join)(struct sock *sk, int ifindex,
-				 const struct in6_addr *addr);
-	int (*ipv6_sock_mc_drop)(struct sock *sk, int ifindex,
-				 const struct in6_addr *addr);
-	int (*ipv6_dst_lookup)(struct net *net, struct sock *sk,
-			       struct dst_entry **dst, struct flowi6 *fl6);
-
-	struct fib6_table *(*fib6_get_table)(struct net *net, u32 id);
-	struct fib6_info *(*fib6_lookup)(struct net *net, int oif,
-					 struct flowi6 *fl6, int flags);
-	struct fib6_info *(*fib6_table_lookup)(struct net *net,
-					      struct fib6_table *table,
-					      int oif, struct flowi6 *fl6,
-					      int flags);
-	struct fib6_info *(*fib6_multipath_select)(const struct net *net,
-						   struct fib6_info *f6i,
-						   struct flowi6 *fl6, int oif,
-						   const struct sk_buff *skb,
-						   int strict);
-	u32 (*ip6_mtu_from_fib6)(struct fib6_info *f6i, struct in6_addr *daddr,
-				 struct in6_addr *saddr);
-
-	void (*udpv6_encap_enable)(void);
-	void (*ndisc_send_na)(struct net_device *dev, const struct in6_addr *daddr,
-			      const struct in6_addr *solicited_addr,
-			      bool router, bool solicited, bool override, bool inc_opt);
-	struct neigh_table *nd_tbl;
-};
-extern const struct ipv6_stub *ipv6_stub __read_mostly;
-
-/* A stub used by bpf helpers. Similarly ugly as ipv6_stub */
-struct ipv6_bpf_stub {
-	int (*inet6_bind)(struct sock *sk, struct sockaddr *uaddr, int addr_len,
-			  bool force_bind_address_no_port, bool with_lock);
-};
-extern const struct ipv6_bpf_stub *ipv6_bpf_stub __read_mostly;
-
 /*
  * identify MLD packets for MLD filter exceptions
  */
diff --git a/include/net/ipv6_stubs.h b/include/net/ipv6_stubs.h
new file mode 100644
index 000000000000..609e13d12573
--- /dev/null
+++ b/include/net/ipv6_stubs.h
@@ -0,0 +1,58 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _IPV6_STUBS_H
+#define _IPV6_STUBS_H
+
+#include <linux/in6.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <net/dst.h>
+#include <net/flow.h>
+#include <net/neighbour.h>
+#include <net/sock.h>
+
+/* structs from net/ip6_fib.h */
+struct fib6_info;
+
+/* This is ugly, ideally these symbols should be built
+ * into the core kernel.
+ */
+struct ipv6_stub {
+	int (*ipv6_sock_mc_join)(struct sock *sk, int ifindex,
+				 const struct in6_addr *addr);
+	int (*ipv6_sock_mc_drop)(struct sock *sk, int ifindex,
+				 const struct in6_addr *addr);
+	int (*ipv6_dst_lookup)(struct net *net, struct sock *sk,
+			       struct dst_entry **dst, struct flowi6 *fl6);
+	int (*ipv6_route_input)(struct sk_buff *skb);
+
+	struct fib6_table *(*fib6_get_table)(struct net *net, u32 id);
+	struct fib6_info *(*fib6_lookup)(struct net *net, int oif,
+					 struct flowi6 *fl6, int flags);
+	struct fib6_info *(*fib6_table_lookup)(struct net *net,
+					      struct fib6_table *table,
+					      int oif, struct flowi6 *fl6,
+					      int flags);
+	struct fib6_info *(*fib6_multipath_select)(const struct net *net,
+						   struct fib6_info *f6i,
+						   struct flowi6 *fl6, int oif,
+						   const struct sk_buff *skb,
+						   int strict);
+	u32 (*ip6_mtu_from_fib6)(struct fib6_info *f6i, struct in6_addr *daddr,
+				 struct in6_addr *saddr);
+
+	void (*udpv6_encap_enable)(void);
+	void (*ndisc_send_na)(struct net_device *dev, const struct in6_addr *daddr,
+			      const struct in6_addr *solicited_addr,
+			      bool router, bool solicited, bool override, bool inc_opt);
+	struct neigh_table *nd_tbl;
+};
+extern const struct ipv6_stub *ipv6_stub __read_mostly;
+
+/* A stub used by bpf helpers. Similarly ugly as ipv6_stub */
+struct ipv6_bpf_stub {
+	int (*inet6_bind)(struct sock *sk, struct sockaddr *uaddr, int addr_len,
+			  bool force_bind_address_no_port, bool with_lock);
+};
+extern const struct ipv6_bpf_stub *ipv6_bpf_stub __read_mostly;
+
+#endif
diff --git a/include/net/udp_tunnel.h b/include/net/udp_tunnel.h
index fe680ab6b15a..859876827acf 100644
--- a/include/net/udp_tunnel.h
+++ b/include/net/udp_tunnel.h
@@ -7,7 +7,7 @@
 
 #if IS_ENABLED(CONFIG_IPV6)
 #include <net/ipv6.h>
-#include <net/addrconf.h>
+#include <net/ipv6_stubs.h>
 #endif
 
 struct udp_port_cfg {
diff --git a/net/bridge/br_arp_nd_proxy.c b/net/bridge/br_arp_nd_proxy.c
index d42e3904b498..e6cea3c383f2 100644
--- a/net/bridge/br_arp_nd_proxy.c
+++ b/net/bridge/br_arp_nd_proxy.c
@@ -21,6 +21,7 @@
 #include <linux/if_vlan.h>
 #include <linux/inetdevice.h>
 #include <net/addrconf.h>
+#include <net/ipv6_stubs.h>
 #if IS_ENABLED(CONFIG_IPV6)
 #include <net/ip6_checksum.h>
 #endif
diff --git a/net/core/filter.c b/net/core/filter.c
index 40b3af05c883..4a9d3f15ceb6 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -68,6 +68,7 @@
 #include <linux/seg6_local.h>
 #include <net/seg6.h>
 #include <net/seg6_local.h>
+#include <net/ipv6_stubs.h>
 
 /**
  *	sk_filter_trim_cap - run a packet through a socket filter
diff --git a/net/core/lwt_bpf.c b/net/core/lwt_bpf.c
index a648568c5e8f..6198fb51c09f 100644
--- a/net/core/lwt_bpf.c
+++ b/net/core/lwt_bpf.c
@@ -16,6 +16,7 @@
 #include <linux/types.h>
 #include <linux/bpf.h>
 #include <net/lwtunnel.h>
+#include <net/ipv6_stubs.h>
 
 struct bpf_lwt_prog {
 	struct bpf_prog *prog;
diff --git a/net/ipv6/addrconf_core.c b/net/ipv6/addrconf_core.c
index 5cd0029d930e..0cdc8705f7dc 100644
--- a/net/ipv6/addrconf_core.c
+++ b/net/ipv6/addrconf_core.c
@@ -5,7 +5,7 @@
 
 #include <linux/export.h>
 #include <net/ipv6.h>
-#include <net/addrconf.h>
+#include <net/ipv6_stubs.h>
 #include <net/ip.h>
 
 /* if ipv6 module registers this function is used by xfrm to force all
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index 79fcd9550fd2..0f2a826e9d75 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -56,6 +56,7 @@
 #include <net/transp_v6.h>
 #include <net/ip6_route.h>
 #include <net/addrconf.h>
+#include <net/ipv6_stubs.h>
 #include <net/ndisc.h>
 #ifdef CONFIG_IPV6_TUNNEL
 #include <net/ip6_tunnel.h>
diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c
index d5a4db5b3fe7..9a4d31a56ddc 100644
--- a/net/mpls/af_mpls.c
+++ b/net/mpls/af_mpls.c
@@ -22,7 +22,7 @@
 #if IS_ENABLED(CONFIG_IPV6)
 #include <net/ipv6.h>
 #endif
-#include <net/addrconf.h>
+#include <net/ipv6_stubs.h>
 #include <net/nexthop.h>
 #include "internal.h"
 
diff --git a/net/tipc/udp_media.c b/net/tipc/udp_media.c
index 382c84d9339d..76f43b333c99 100644
--- a/net/tipc/udp_media.c
+++ b/net/tipc/udp_media.c
@@ -44,7 +44,7 @@
 #include <net/sock.h>
 #include <net/ip.h>
 #include <net/udp_tunnel.h>
-#include <net/addrconf.h>
+#include <net/ipv6_stubs.h>
 #include <linux/tipc_netlink.h>
 #include "core.h"
 #include "addr.h"
-- 
2.17.1


[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #3: 0002-net-ipv6-add-net-argument-to-ip6_dst_lookup_flow.patch --]
[-- Type: text/x-patch; name="0002-net-ipv6-add-net-argument-to-ip6_dst_lookup_flow.patch", Size: 9497 bytes --]

From aa1914ffe4c5a5328920c6b1be58a23d0f997195 Mon Sep 17 00:00:00 2001
From: Sabrina Dubroca <sd@queasysnail.net>
Date: Wed, 4 Dec 2019 15:35:52 +0100
Subject: [PATCH 2/3] net: ipv6: add net argument to ip6_dst_lookup_flow

[ Upstream commit c4e85f73afb6384123e5ef1bba3315b2e3ad031e ]

Fixes CVE-2020-1749
Backported from v5.5-rc1
Patch 2/3

This will be used in the conversion of ipv6_stub to ip6_dst_lookup_flow,
as some modules currently pass a net argument without a socket to
ip6_dst_lookup. This is equivalent to commit 343d60aada5a ("ipv6: change
ipv6_stub_impl.ipv6_dst_lookup to take net argument").

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Carsten Schmid <carsten_schmid@mentor.com>
---
 include/net/ipv6.h               | 2 +-
 net/dccp/ipv6.c                  | 6 +++---
 net/ipv6/af_inet6.c              | 2 +-
 net/ipv6/datagram.c              | 2 +-
 net/ipv6/inet6_connection_sock.c | 4 ++--
 net/ipv6/ip6_output.c            | 8 ++++----
 net/ipv6/raw.c                   | 2 +-
 net/ipv6/syncookies.c            | 2 +-
 net/ipv6/tcp_ipv6.c              | 4 ++--
 net/l2tp/l2tp_ip6.c              | 2 +-
 net/sctp/ipv6.c                  | 4 ++--
 11 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index ff33f498c137..4c2e40882e88 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -959,7 +959,7 @@ static inline struct sk_buff *ip6_finish_skb(struct sock *sk)
 
 int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst,
 		   struct flowi6 *fl6);
-struct dst_entry *ip6_dst_lookup_flow(const struct sock *sk, struct flowi6 *fl6,
+struct dst_entry *ip6_dst_lookup_flow(struct net *net, const struct sock *sk, struct flowi6 *fl6,
 				      const struct in6_addr *final_dst);
 struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
 					 const struct in6_addr *final_dst,
diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index 58a401e9cf09..b438bed6749d 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -211,7 +211,7 @@ static int dccp_v6_send_response(const struct sock *sk, struct request_sock *req
 	final_p = fl6_update_dst(&fl6, rcu_dereference(np->opt), &final);
 	rcu_read_unlock();
 
-	dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
+	dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
 	if (IS_ERR(dst)) {
 		err = PTR_ERR(dst);
 		dst = NULL;
@@ -282,7 +282,7 @@ static void dccp_v6_ctl_send_reset(const struct sock *sk, struct sk_buff *rxskb)
 	security_skb_classify_flow(rxskb, flowi6_to_flowi(&fl6));
 
 	/* sk = NULL, but it is safe for now. RST socket required. */
-	dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL);
+	dst = ip6_dst_lookup_flow(sock_net(ctl_sk), ctl_sk, &fl6, NULL);
 	if (!IS_ERR(dst)) {
 		skb_dst_set(skb, dst);
 		ip6_xmit(ctl_sk, skb, &fl6, 0, NULL, 0);
@@ -912,7 +912,7 @@ static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 	opt = rcu_dereference_protected(np->opt, lockdep_sock_is_held(sk));
 	final_p = fl6_update_dst(&fl6, opt, &final);
 
-	dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
+	dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
 	if (IS_ERR(dst)) {
 		err = PTR_ERR(dst);
 		goto failure;
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index 0f2a826e9d75..45b75bc99122 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -741,7 +741,7 @@ int inet6_sk_rebuild_header(struct sock *sk)
 					 &final);
 		rcu_read_unlock();
 
-		dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
+		dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
 		if (IS_ERR(dst)) {
 			sk->sk_route_caps = 0;
 			sk->sk_err_soft = -PTR_ERR(dst);
diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index 971a0fdf1fbc..727f958dd869 100644
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -89,7 +89,7 @@ int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr)
 	final_p = fl6_update_dst(&fl6, opt, &final);
 	rcu_read_unlock();
 
-	dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
+	dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
 	if (IS_ERR(dst)) {
 		err = PTR_ERR(dst);
 		goto out;
diff --git a/net/ipv6/inet6_connection_sock.c b/net/ipv6/inet6_connection_sock.c
index 890adadcda16..92fe9e565da0 100644
--- a/net/ipv6/inet6_connection_sock.c
+++ b/net/ipv6/inet6_connection_sock.c
@@ -52,7 +52,7 @@ struct dst_entry *inet6_csk_route_req(const struct sock *sk,
 	fl6->flowi6_uid = sk->sk_uid;
 	security_req_classify_flow(req, flowi6_to_flowi(fl6));
 
-	dst = ip6_dst_lookup_flow(sk, fl6, final_p);
+	dst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p);
 	if (IS_ERR(dst))
 		return NULL;
 
@@ -107,7 +107,7 @@ static struct dst_entry *inet6_csk_route_socket(struct sock *sk,
 
 	dst = __inet6_csk_dst_check(sk, np->dst_cookie);
 	if (!dst) {
-		dst = ip6_dst_lookup_flow(sk, fl6, final_p);
+		dst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p);
 
 		if (!IS_ERR(dst))
 			ip6_dst_store(sk, dst, NULL, NULL);
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 9886a84c2511..22665e3638ac 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1071,19 +1071,19 @@ EXPORT_SYMBOL_GPL(ip6_dst_lookup);
  *	It returns a valid dst pointer on success, or a pointer encoded
  *	error code.
  */
-struct dst_entry *ip6_dst_lookup_flow(const struct sock *sk, struct flowi6 *fl6,
+struct dst_entry *ip6_dst_lookup_flow(struct net *net, const struct sock *sk, struct flowi6 *fl6,
 				      const struct in6_addr *final_dst)
 {
 	struct dst_entry *dst = NULL;
 	int err;
 
-	err = ip6_dst_lookup_tail(sock_net(sk), sk, &dst, fl6);
+	err = ip6_dst_lookup_tail(net, sk, &dst, fl6);
 	if (err)
 		return ERR_PTR(err);
 	if (final_dst)
 		fl6->daddr = *final_dst;
 
-	return xfrm_lookup_route(sock_net(sk), dst, flowi6_to_flowi(fl6), sk, 0);
+	return xfrm_lookup_route(net, dst, flowi6_to_flowi(fl6), sk, 0);
 }
 EXPORT_SYMBOL_GPL(ip6_dst_lookup_flow);
 
@@ -1115,7 +1115,7 @@ struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
 	if (dst)
 		return dst;
 
-	dst = ip6_dst_lookup_flow(sk, fl6, final_dst);
+	dst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_dst);
 	if (connected && !IS_ERR(dst))
 		ip6_sk_dst_store_flow(sk, dst_clone(dst), fl6);
 
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index a41156a00dd4..8d19729f8516 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -928,7 +928,7 @@ static int rawv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 
 	fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
 
-	dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
+	dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
 	if (IS_ERR(dst)) {
 		err = PTR_ERR(dst);
 		goto out;
diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c
index e997141aed8c..a377be8a9fb4 100644
--- a/net/ipv6/syncookies.c
+++ b/net/ipv6/syncookies.c
@@ -240,7 +240,7 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb)
 		fl6.flowi6_uid = sk->sk_uid;
 		security_req_classify_flow(req, flowi6_to_flowi(&fl6));
 
-		dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
+		dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
 		if (IS_ERR(dst))
 			goto out_free;
 	}
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 7b0c2498f461..2e76ebfdc907 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -268,7 +268,7 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 
 	security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
 
-	dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
+	dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
 	if (IS_ERR(dst)) {
 		err = PTR_ERR(dst);
 		goto failure;
@@ -885,7 +885,7 @@ static void tcp_v6_send_response(const struct sock *sk, struct sk_buff *skb, u32
 	 * Underlying function will use this to retrieve the network
 	 * namespace
 	 */
-	dst = ip6_dst_lookup_flow(ctl_sk, &fl6, NULL);
+	dst = ip6_dst_lookup_flow(sock_net(ctl_sk), ctl_sk, &fl6, NULL);
 	if (!IS_ERR(dst)) {
 		skb_dst_set(buff, dst);
 		ip6_xmit(ctl_sk, buff, &fl6, fl6.flowi6_mark, NULL, tclass);
diff --git a/net/l2tp/l2tp_ip6.c b/net/l2tp/l2tp_ip6.c
index 37a69df17cab..2f28f9910b92 100644
--- a/net/l2tp/l2tp_ip6.c
+++ b/net/l2tp/l2tp_ip6.c
@@ -619,7 +619,7 @@ static int l2tp_ip6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 
 	fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
 
-	dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
+	dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
 	if (IS_ERR(dst)) {
 		err = PTR_ERR(dst);
 		goto out;
diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c
index 4fede55b9010..4277b720c26e 100644
--- a/net/sctp/ipv6.c
+++ b/net/sctp/ipv6.c
@@ -287,7 +287,7 @@ static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
 	final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
 	rcu_read_unlock();
 
-	dst = ip6_dst_lookup_flow(sk, fl6, final_p);
+	dst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p);
 	if (!asoc || saddr)
 		goto out;
 
@@ -340,7 +340,7 @@ static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
 		fl6->saddr = laddr->a.v6.sin6_addr;
 		fl6->fl6_sport = laddr->a.v6.sin6_port;
 		final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
-		bdst = ip6_dst_lookup_flow(sk, fl6, final_p);
+		bdst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p);
 
 		if (IS_ERR(bdst))
 			continue;
-- 
2.17.1


[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #4: 0003-net-ipv6_stub-use-ip6_dst_lookup_flow-instead-of-ip6.patch --]
[-- Type: text/x-patch; name="0003-net-ipv6_stub-use-ip6_dst_lookup_flow-instead-of-ip6.patch", Size: 9600 bytes --]

From 9c215c825018e1195c9f1bfad24f4f224591a274 Mon Sep 17 00:00:00 2001
From: Sabrina Dubroca <sd@queasysnail.net>
Date: Wed, 4 Dec 2019 15:35:53 +0100
Subject: [PATCH 3/3] net: ipv6_stub: use ip6_dst_lookup_flow instead of
 ip6_dst_lookup

[ Upstream commit 6c8991f41546c3c472503dff1ea9daaddf9331c2 ]

Fixes CVE-2020-1749
Backported from v5.5-rc1
Patch 3/3

ipv6_stub uses the ip6_dst_lookup function to allow other modules to
perform IPv6 lookups. However, this function skips the XFRM layer
entirely.

All users of ipv6_stub->ip6_dst_lookup use ip_route_output_flow (via the
ip_route_output_key and ip_route_output helpers) for their IPv4 lookups,
which calls xfrm_lookup_route(). This patch fixes this inconsistent
behavior by switching the stub to ip6_dst_lookup_flow, which also calls
xfrm_lookup_route().

This requires some changes in all the callers, as these two functions
take different arguments and have different return types.

Fixes: 5f81bd2e5d80 ("ipv6: export a stub for IPv6 symbols used by vxlan")
Reported-by: Xiumei Mu <xmu@redhat.com>
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Carsten Schmid <carsten_schmid@mentor.com>
---
 drivers/infiniband/core/addr.c                  |  7 +++----
 drivers/infiniband/sw/rxe/rxe_net.c             |  8 +++++---
 drivers/net/ethernet/mellanox/mlx5/core/en_tc.c |  9 ++++-----
 drivers/net/geneve.c                            |  4 +++-
 drivers/net/vxlan.c                             |  8 +++-----
 include/net/ipv6_stubs.h                        |  6 ++++--
 net/ipv6/addrconf_core.c                        | 11 ++++++-----
 net/ipv6/af_inet6.c                             |  2 +-
 net/mpls/af_mpls.c                              |  7 +++----
 net/tipc/udp_media.c                            |  9 ++++++---
 10 files changed, 38 insertions(+), 33 deletions(-)

diff --git a/drivers/infiniband/core/addr.c b/drivers/infiniband/core/addr.c
index 327ca9ff8127..e77b5bdca2bd 100644
--- a/drivers/infiniband/core/addr.c
+++ b/drivers/infiniband/core/addr.c
@@ -408,16 +408,15 @@ static int addr6_resolve(struct sockaddr_in6 *src_in,
 	struct flowi6 fl6;
 	struct dst_entry *dst;
 	struct rt6_info *rt;
-	int ret;
 
 	memset(&fl6, 0, sizeof fl6);
 	fl6.daddr = dst_in->sin6_addr;
 	fl6.saddr = src_in->sin6_addr;
 	fl6.flowi6_oif = addr->bound_dev_if;
 
-	ret = ipv6_stub->ipv6_dst_lookup(addr->net, NULL, &dst, &fl6);
-	if (ret < 0)
-		return ret;
+	dst = ipv6_stub->ipv6_dst_lookup_flow(addr->net, NULL, &fl6, NULL);
+	if (IS_ERR(dst))
+		return PTR_ERR(dst);
 
 	rt = (struct rt6_info *)dst;
 	if (ipv6_addr_any(&src_in->sin6_addr)) {
diff --git a/drivers/infiniband/sw/rxe/rxe_net.c b/drivers/infiniband/sw/rxe/rxe_net.c
index 54add70c22b5..7903bd5c639e 100644
--- a/drivers/infiniband/sw/rxe/rxe_net.c
+++ b/drivers/infiniband/sw/rxe/rxe_net.c
@@ -154,10 +154,12 @@ static struct dst_entry *rxe_find_route6(struct net_device *ndev,
 	memcpy(&fl6.daddr, daddr, sizeof(*daddr));
 	fl6.flowi6_proto = IPPROTO_UDP;
 
-	if (unlikely(ipv6_stub->ipv6_dst_lookup(sock_net(recv_sockets.sk6->sk),
-						recv_sockets.sk6->sk, &ndst, &fl6))) {
+	ndst = ipv6_stub->ipv6_dst_lookup_flow(sock_net(recv_sockets.sk6->sk),
+					       recv_sockets.sk6->sk, &fl6,
+					       NULL);
+	if (unlikely(IS_ERR(ndst))) {
 		pr_err_ratelimited("no route to %pI6\n", daddr);
-		goto put;
+		return NULL;
 	}
 
 	if (unlikely(ndst->error)) {
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
index f1c26742572b..b718234643b8 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
@@ -2218,12 +2218,11 @@ static int mlx5e_route_lookup_ipv6(struct mlx5e_priv *priv,
 #if IS_ENABLED(CONFIG_INET) && IS_ENABLED(CONFIG_IPV6)
 	struct mlx5e_rep_priv *uplink_rpriv;
 	struct mlx5_eswitch *esw = priv->mdev->priv.eswitch;
-	int ret;
 
-	ret = ipv6_stub->ipv6_dst_lookup(dev_net(mirred_dev), NULL, &dst,
-					 fl6);
-	if (ret < 0)
-		return ret;
+	dst = ipv6_stub->ipv6_dst_lookup_flow(dev_net(mirred_dev), NULL, fl6,
+					      NULL);
+	if (IS_ERR(dst))
+		return PTR_ERR(dst);
 
 	if (!(*out_ttl))
 		*out_ttl = ip6_dst_hoplimit(dst);
diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index d808442f98ca..957454b1cf1b 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -802,7 +802,9 @@ static struct dst_entry *geneve_get_v6_dst(struct sk_buff *skb,
 		if (dst)
 			return dst;
 	}
-	if (ipv6_stub->ipv6_dst_lookup(geneve->net, gs6->sock->sk, &dst, fl6)) {
+	dst = ipv6_stub->ipv6_dst_lookup_flow(geneve->net, gs6->sock->sk, fl6,
+					      NULL);
+	if (IS_ERR(dst)) {
 		netdev_dbg(dev, "no route to %pI6\n", &fl6->daddr);
 		return ERR_PTR(-ENETUNREACH);
 	}
diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index eae6723ae5ea..368ebdc917b7 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -1964,7 +1964,6 @@ static struct dst_entry *vxlan6_get_route(struct vxlan_dev *vxlan,
 	bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
 	struct dst_entry *ndst;
 	struct flowi6 fl6;
-	int err;
 
 	if (!sock6)
 		return ERR_PTR(-EIO);
@@ -1987,10 +1986,9 @@ static struct dst_entry *vxlan6_get_route(struct vxlan_dev *vxlan,
 	fl6.fl6_dport = dport;
 	fl6.fl6_sport = sport;
 
-	err = ipv6_stub->ipv6_dst_lookup(vxlan->net,
-					 sock6->sock->sk,
-					 &ndst, &fl6);
-	if (unlikely(err < 0)) {
+	ndst = ipv6_stub->ipv6_dst_lookup_flow(vxlan->net, sock6->sock->sk,
+					       &fl6, NULL);
+	if (unlikely(IS_ERR(ndst))) {
 		netdev_dbg(dev, "no route to %pI6\n", daddr);
 		return ERR_PTR(-ENETUNREACH);
 	}
diff --git a/include/net/ipv6_stubs.h b/include/net/ipv6_stubs.h
index 609e13d12573..065d004f5257 100644
--- a/include/net/ipv6_stubs.h
+++ b/include/net/ipv6_stubs.h
@@ -21,8 +21,10 @@ struct ipv6_stub {
 				 const struct in6_addr *addr);
 	int (*ipv6_sock_mc_drop)(struct sock *sk, int ifindex,
 				 const struct in6_addr *addr);
-	int (*ipv6_dst_lookup)(struct net *net, struct sock *sk,
-			       struct dst_entry **dst, struct flowi6 *fl6);
+	struct dst_entry *(*ipv6_dst_lookup_flow)(struct net *net,
+						  const struct sock *sk,
+						  struct flowi6 *fl6,
+						  const struct in6_addr *final_dst);
 	int (*ipv6_route_input)(struct sk_buff *skb);
 
 	struct fib6_table *(*fib6_get_table)(struct net *net, u32 id);
diff --git a/net/ipv6/addrconf_core.c b/net/ipv6/addrconf_core.c
index 0cdc8705f7dc..2f927423bca2 100644
--- a/net/ipv6/addrconf_core.c
+++ b/net/ipv6/addrconf_core.c
@@ -127,11 +127,12 @@ int inet6addr_validator_notifier_call_chain(unsigned long val, void *v)
 }
 EXPORT_SYMBOL(inet6addr_validator_notifier_call_chain);
 
-static int eafnosupport_ipv6_dst_lookup(struct net *net, struct sock *u1,
-					struct dst_entry **u2,
-					struct flowi6 *u3)
+static struct dst_entry *eafnosupport_ipv6_dst_lookup_flow(struct net *net,
+							   const struct sock *sk,
+							   struct flowi6 *fl6,
+							   const struct in6_addr *final_dst)
 {
-	return -EAFNOSUPPORT;
+	return ERR_PTR(-EAFNOSUPPORT);
 }
 
 static struct fib6_table *eafnosupport_fib6_get_table(struct net *net, u32 id)
@@ -169,7 +170,7 @@ eafnosupport_ip6_mtu_from_fib6(struct fib6_info *f6i, struct in6_addr *daddr,
 }
 
 const struct ipv6_stub *ipv6_stub __read_mostly = &(struct ipv6_stub) {
-	.ipv6_dst_lookup   = eafnosupport_ipv6_dst_lookup,
+	.ipv6_dst_lookup_flow = eafnosupport_ipv6_dst_lookup_flow,
 	.fib6_get_table    = eafnosupport_fib6_get_table,
 	.fib6_table_lookup = eafnosupport_fib6_table_lookup,
 	.fib6_lookup       = eafnosupport_fib6_lookup,
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index 45b75bc99122..234340c3c050 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -905,7 +905,7 @@ static struct pernet_operations inet6_net_ops = {
 static const struct ipv6_stub ipv6_stub_impl = {
 	.ipv6_sock_mc_join = ipv6_sock_mc_join,
 	.ipv6_sock_mc_drop = ipv6_sock_mc_drop,
-	.ipv6_dst_lookup   = ip6_dst_lookup,
+	.ipv6_dst_lookup_flow = ip6_dst_lookup_flow,
 	.fib6_get_table	   = fib6_get_table,
 	.fib6_table_lookup = fib6_table_lookup,
 	.fib6_lookup       = fib6_lookup,
diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c
index 9a4d31a56ddc..0e19438d2c78 100644
--- a/net/mpls/af_mpls.c
+++ b/net/mpls/af_mpls.c
@@ -618,16 +618,15 @@ static struct net_device *inet6_fib_lookup_dev(struct net *net,
 	struct net_device *dev;
 	struct dst_entry *dst;
 	struct flowi6 fl6;
-	int err;
 
 	if (!ipv6_stub)
 		return ERR_PTR(-EAFNOSUPPORT);
 
 	memset(&fl6, 0, sizeof(fl6));
 	memcpy(&fl6.daddr, addr, sizeof(struct in6_addr));
-	err = ipv6_stub->ipv6_dst_lookup(net, NULL, &dst, &fl6);
-	if (err)
-		return ERR_PTR(err);
+	dst = ipv6_stub->ipv6_dst_lookup_flow(net, NULL, &fl6, NULL);
+	if (IS_ERR(dst))
+		return ERR_CAST(dst);
 
 	dev = dst->dev;
 	dev_hold(dev);
diff --git a/net/tipc/udp_media.c b/net/tipc/udp_media.c
index 76f43b333c99..d2240a47691f 100644
--- a/net/tipc/udp_media.c
+++ b/net/tipc/udp_media.c
@@ -189,10 +189,13 @@ static int tipc_udp_xmit(struct net *net, struct sk_buff *skb,
 			.saddr = src->ipv6,
 			.flowi6_proto = IPPROTO_UDP
 		};
-		err = ipv6_stub->ipv6_dst_lookup(net, ub->ubsock->sk, &ndst,
-						 &fl6);
-		if (err)
+		ndst = ipv6_stub->ipv6_dst_lookup_flow(net,
+						       ub->ubsock->sk,
+						       &fl6, NULL);
+		if (IS_ERR(ndst)) {
+			err = PTR_ERR(ndst);
 			goto tx_error;
+		}
 		ttl = ip6_dst_hoplimit(ndst);
 		err = udp_tunnel6_xmit_skb(ndst, ub->ubsock->sk, skb, NULL,
 					   &src->ipv6, &dst->ipv6, 0, ttl, 0,
-- 
2.17.1