summaryrefslogtreecommitdiff
path: root/net/ipv6
AgeCommit message (Collapse)AuthorFilesLines
2020-06-30ip6_gre: fix use-after-free in ip6gre_tunnel_lookup()Taehee Yoo1-3/+6
[ Upstream commit dafabb6590cb15f300b77c095d50312e2c7c8e0f ] In the datapath, the ip6gre_tunnel_lookup() is used and it internally uses fallback tunnel device pointer, which is fb_tunnel_dev. This pointer variable should be set to NULL when a fb interface is deleted. But there is no routine to set fb_tunnel_dev pointer to NULL. So, this pointer will be still used after interface is deleted and it eventually results in the use-after-free problem. Test commands: ip netns add A ip netns add B ip link add eth0 type veth peer name eth1 ip link set eth0 netns A ip link set eth1 netns B ip netns exec A ip link set lo up ip netns exec A ip link set eth0 up ip netns exec A ip link add ip6gre1 type ip6gre local fc:0::1 \ remote fc:0::2 ip netns exec A ip -6 a a fc:100::1/64 dev ip6gre1 ip netns exec A ip link set ip6gre1 up ip netns exec A ip -6 a a fc:0::1/64 dev eth0 ip netns exec A ip link set ip6gre0 up ip netns exec B ip link set lo up ip netns exec B ip link set eth1 up ip netns exec B ip link add ip6gre1 type ip6gre local fc:0::2 \ remote fc:0::1 ip netns exec B ip -6 a a fc:100::2/64 dev ip6gre1 ip netns exec B ip link set ip6gre1 up ip netns exec B ip -6 a a fc:0::2/64 dev eth1 ip netns exec B ip link set ip6gre0 up ip netns exec A ping fc:100::2 -s 60000 & ip netns del B Splat looks like: [ 73.087285][ C1] BUG: KASAN: use-after-free in ip6gre_tunnel_lookup+0x1064/0x13f0 [ip6_gre] [ 73.088361][ C1] Read of size 4 at addr ffff888040559218 by task ping/1429 [ 73.089317][ C1] [ 73.089638][ C1] CPU: 1 PID: 1429 Comm: ping Not tainted 5.7.0+ #602 [ 73.090531][ C1] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 [ 73.091725][ C1] Call Trace: [ 73.092160][ C1] <IRQ> [ 73.092556][ C1] dump_stack+0x96/0xdb [ 73.093122][ C1] print_address_description.constprop.6+0x2cc/0x450 [ 73.094016][ C1] ? ip6gre_tunnel_lookup+0x1064/0x13f0 [ip6_gre] [ 73.094894][ C1] ? ip6gre_tunnel_lookup+0x1064/0x13f0 [ip6_gre] [ 73.095767][ C1] ? ip6gre_tunnel_lookup+0x1064/0x13f0 [ip6_gre] [ 73.096619][ C1] kasan_report+0x154/0x190 [ 73.097209][ C1] ? ip6gre_tunnel_lookup+0x1064/0x13f0 [ip6_gre] [ 73.097989][ C1] ip6gre_tunnel_lookup+0x1064/0x13f0 [ip6_gre] [ 73.098750][ C1] ? gre_del_protocol+0x60/0x60 [gre] [ 73.099500][ C1] gre_rcv+0x1c5/0x1450 [ip6_gre] [ 73.100199][ C1] ? ip6gre_header+0xf00/0xf00 [ip6_gre] [ 73.100985][ C1] ? rcu_read_lock_sched_held+0xc0/0xc0 [ 73.101830][ C1] ? ip6_input_finish+0x5/0xf0 [ 73.102483][ C1] ip6_protocol_deliver_rcu+0xcbb/0x1510 [ 73.103296][ C1] ip6_input_finish+0x5b/0xf0 [ 73.103920][ C1] ip6_input+0xcd/0x2c0 [ 73.104473][ C1] ? ip6_input_finish+0xf0/0xf0 [ 73.105115][ C1] ? rcu_read_lock_held+0x90/0xa0 [ 73.105783][ C1] ? rcu_read_lock_sched_held+0xc0/0xc0 [ 73.106548][ C1] ipv6_rcv+0x1f1/0x300 [ ... ] Suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Fixes: c12b395a4664 ("gre: Support GRE over IPv6") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-30mld: fix memory leak in ipv6_mc_destroy_dev()Wang Hai1-0/+1
[ Upstream commit ea2fce88d2fd678ed9d45354ff49b73f1d5615dd ] Commit a84d01647989 ("mld: fix memory leak in mld_del_delrec()") fixed the memory leak of MLD, but missing the ipv6_mc_destroy_dev() path, in which mca_sources are leaked after ma_put(). Using ip6_mc_clear_src() to take care of the missing free. BUG: memory leak unreferenced object 0xffff8881113d3180 (size 64): comm "syz-executor071", pid 389, jiffies 4294887985 (age 17.943s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 ff 02 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 00 ................ backtrace: [<000000002cbc483c>] kmalloc include/linux/slab.h:555 [inline] [<000000002cbc483c>] kzalloc include/linux/slab.h:669 [inline] [<000000002cbc483c>] ip6_mc_add1_src net/ipv6/mcast.c:2237 [inline] [<000000002cbc483c>] ip6_mc_add_src+0x7f5/0xbb0 net/ipv6/mcast.c:2357 [<0000000058b8b1ff>] ip6_mc_source+0xe0c/0x1530 net/ipv6/mcast.c:449 [<000000000bfc4fb5>] do_ipv6_setsockopt.isra.12+0x1b2c/0x3b30 net/ipv6/ipv6_sockglue.c:754 [<00000000e4e7a722>] ipv6_setsockopt+0xda/0x150 net/ipv6/ipv6_sockglue.c:950 [<0000000029260d9a>] rawv6_setsockopt+0x45/0x100 net/ipv6/raw.c:1081 [<000000005c1b46f9>] __sys_setsockopt+0x131/0x210 net/socket.c:2132 [<000000008491f7db>] __do_sys_setsockopt net/socket.c:2148 [inline] [<000000008491f7db>] __se_sys_setsockopt net/socket.c:2145 [inline] [<000000008491f7db>] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2145 [<00000000c7bc11c5>] do_syscall_64+0xa1/0x530 arch/x86/entry/common.c:295 [<000000005fb7a3f3>] entry_SYSCALL_64_after_hwframe+0x49/0xb3 Fixes: 1666d49e1d41 ("mld: do not remove mld souce list info when set link down") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Wang Hai <wanghai38@huawei.com> Acked-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-20ipv6: fix IPV6_ADDRFORM operation logicHangbin Liu1-6/+7
[ Upstream commit 79a1f0ccdbb4ad700590f61b00525b390cb53905 ] Socket option IPV6_ADDRFORM supports UDP/UDPLITE and TCP at present. Previously the checking logic looks like: if (sk->sk_protocol == IPPROTO_UDP || sk->sk_protocol == IPPROTO_UDPLITE) do_some_check; else if (sk->sk_protocol != IPPROTO_TCP) break; After commit b6f6118901d1 ("ipv6: restrict IPV6_ADDRFORM operation"), TCP was blocked as the logic changed to: if (sk->sk_protocol == IPPROTO_UDP || sk->sk_protocol == IPPROTO_UDPLITE) do_some_check; else if (sk->sk_protocol == IPPROTO_TCP) do_some_check; break; else break; Then after commit 82c9ae440857 ("ipv6: fix restrict IPV6_ADDRFORM operation") UDP/UDPLITE were blocked as the logic changed to: if (sk->sk_protocol == IPPROTO_UDP || sk->sk_protocol == IPPROTO_UDPLITE) do_some_check; if (sk->sk_protocol == IPPROTO_TCP) do_some_check; if (sk->sk_protocol != IPPROTO_TCP) break; Fix it by using Eric's code and simply remove the break in TCP check, which looks like: if (sk->sk_protocol == IPPROTO_UDP || sk->sk_protocol == IPPROTO_UDPLITE) do_some_check; else if (sk->sk_protocol == IPPROTO_TCP) do_some_check; else break; Fixes: 82c9ae440857 ("ipv6: fix restrict IPV6_ADDRFORM operation") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-03esp6: get the right proto for transport mode in esp6_gso_encapXin Long1-1/+8
commit 3c96ec56828922e3fe5477f75eb3fc02f98f98b5 upstream. For transport mode, when ipv6 nexthdr is set, the packet format might be like: ---------------------------------------------------- | | dest | | | | ESP | ESP | | IP6 hdr| opts.| ESP | TCP | Data | Trailer | ICV | ---------------------------------------------------- What it wants to get for x-proto in esp6_gso_encap() is the proto that will be set in ESP nexthdr. So it should skip all ipv6 nexthdrs and get the real transport protocol. Othersize, the wrong proto number will be set into ESP nexthdr. This patch is to skip all ipv6 nexthdrs by calling ipv6_skip_exthdr() in esp6_gso_encap(). Fixes: 7862b4058b9f ("esp: Add gso handlers for esp4 and esp6") Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-20Revert "ipv6: add mtu lock check in __ip6_rt_update_pmtu"Maciej Żenczykowski1-2/+4
[ Upstream commit 09454fd0a4ce23cb3d8af65066c91a1bf27120dd ] This reverts commit 19bda36c4299ce3d7e5bce10bebe01764a655a6d: | ipv6: add mtu lock check in __ip6_rt_update_pmtu | | Prior to this patch, ipv6 didn't do mtu lock check in ip6_update_pmtu. | It leaded to that mtu lock doesn't really work when receiving the pkt | of ICMPV6_PKT_TOOBIG. | | This patch is to add mtu lock check in __ip6_rt_update_pmtu just as ipv4 | did in __ip_rt_update_pmtu. The above reasoning is incorrect. IPv6 *requires* icmp based pmtu to work. There's already a comment to this effect elsewhere in the kernel: $ git grep -p -B1 -A3 'RTAX_MTU lock' net/ipv6/route.c=4813= static int rt6_mtu_change_route(struct fib6_info *f6i, void *p_arg) ... /* In IPv6 pmtu discovery is not optional, so that RTAX_MTU lock cannot disable it. We still use this lock to block changes caused by addrconf/ndisc. */ This reverts to the pre-4.9 behaviour. Cc: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Xin Long <lucien.xin@gmail.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Maciej Żenczykowski <maze@google.com> Fixes: 19bda36c4299 ("ipv6: add mtu lock check in __ip6_rt_update_pmtu") Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-20netlabel: cope with NULL catmapPaolo Abeni1-1/+2
[ Upstream commit eead1c2ea2509fd754c6da893a94f0e69e83ebe4 ] The cipso and calipso code can set the MLS_CAT attribute on successful parsing, even if the corresponding catmap has not been allocated, as per current configuration and external input. Later, selinux code tries to access the catmap if the MLS_CAT flag is present via netlbl_catmap_getlong(). That may cause null ptr dereference while processing incoming network traffic. Address the issue setting the MLS_CAT flag only if the catmap is really allocated. Additionally let netlbl_catmap_getlong() cope with NULL catmap. Reported-by: Matthew Sheets <matthew.sheets@gd-ms.com> Fixes: 4b8feff251da ("netlabel: fix the horribly broken catmap functions") Fixes: ceba1832b1b2 ("calipso: Set the calipso socket label to match the secattr.") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-20net: ipv6_stub: use ip6_dst_lookup_flow instead of ip6_dst_lookupSabrina Dubroca2-6/+7
commit 6c8991f41546c3c472503dff1ea9daaddf9331c2 upstream. 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> [bwh: Backported to 4.14: - Drop change in lwt_bpf.c - Delete now-unused "ret" in mlx5e_route_lookup_ipv6() - Initialise "out_dev" in mlx5e_create_encap_header_ipv6() to avoid introducing a spurious "may be used uninitialised" warning - Adjust filenames, context, indentation] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-20net: ipv6: add net argument to ip6_dst_lookup_flowSabrina Dubroca7-12/+12
commit c4e85f73afb6384123e5ef1bba3315b2e3ad031e upstream. 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> [bwh: Backported to 4.14: adjust context] Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-20ipv6: fix cleanup ordering for ip6_mr failureSabrina Dubroca1-3/+3
commit afe49de44c27a89e8e9631c44b5ffadf6ace65e2 upstream. Commit 15e668070a64 ("ipv6: reorder icmpv6_init() and ip6_mr_init()") moved the cleanup label for ipmr_fail, but should have changed the contents of the cleanup labels as well. Now we can end up cleaning up icmpv6 even though it hasn't been initialized (jump to icmp_fail or ipmr_fail). Simply undo things in the reverse order of their initialization. Example of panic (triggered by faking a failure of icmpv6_init): kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN PTI [...] RIP: 0010:__list_del_entry_valid+0x79/0x160 [...] Call Trace: ? lock_release+0x8a0/0x8a0 unregister_pernet_operations+0xd4/0x560 ? ops_free_list+0x480/0x480 ? down_write+0x91/0x130 ? unregister_pernet_subsys+0x15/0x30 ? down_read+0x1b0/0x1b0 ? up_read+0x110/0x110 ? kmem_cache_create_usercopy+0x1b4/0x240 unregister_pernet_subsys+0x1d/0x30 icmpv6_cleanup+0x1d/0x30 inet6_init+0x1b5/0x23f Fixes: 15e668070a64 ("ipv6: reorder icmpv6_init() and ip6_mr_init()") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Signed-off-by: David S. Miller <davem@davemloft.net> Cc: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02xfrm: Always set XFRM_TRANSFORMED in xfrm{4,6}_output_finishDavid Ahern1-2/+0
[ Upstream commit 0c922a4850eba2e668f73a3f1153196e09abb251 ] IPSKB_XFRM_TRANSFORMED and IP6SKB_XFRM_TRANSFORMED are skb flags set by xfrm code to tell other skb handlers that the packet has been passed through the xfrm output functions. Simplify the code and just always set them rather than conditionally based on netfilter enabled thus making the flag available for other users. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02ipv6: fix restrict IPV6_ADDRFORM operationJohn Haxby1-7/+6
[ Upstream commit 82c9ae440857840c56e05d4fb1427ee032531346 ] Commit b6f6118901d1 ("ipv6: restrict IPV6_ADDRFORM operation") fixed a problem found by syzbot an unfortunate logic error meant that it also broke IPV6_ADDRFORM. Rearrange the checks so that the earlier test is just one of the series of checks made before moving the socket from IPv6 to IPv4. Fixes: b6f6118901d1 ("ipv6: restrict IPV6_ADDRFORM operation") Signed-off-by: John Haxby <john.haxby@oracle.com> Cc: stable@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-13ipv6: don't auto-add link-local address to lag portsJarod Wilson1-0/+4
[ Upstream commit 744fdc8233f6aa9582ce08a51ca06e59796a3196 ] Bonding slave and team port devices should not have link-local addresses automatically added to them, as it can interfere with openvswitch being able to properly add tc ingress. Basic reproducer, courtesy of Marcelo: $ ip link add name bond0 type bond $ ip link set dev ens2f0np0 master bond0 $ ip link set dev ens2f1np2 master bond0 $ ip link set dev bond0 up $ ip a s 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: ens2f0np0: <BROADCAST,MULTICAST,SLAVE,UP,LOWER_UP> mtu 1500 qdisc mq master bond0 state UP group default qlen 1000 link/ether 00:0f:53:2f:ea:40 brd ff:ff:ff:ff:ff:ff 5: ens2f1np2: <NO-CARRIER,BROADCAST,MULTICAST,SLAVE,UP> mtu 1500 qdisc mq master bond0 state DOWN group default qlen 1000 link/ether 00:0f:53:2f:ea:40 brd ff:ff:ff:ff:ff:ff 11: bond0: <BROADCAST,MULTICAST,MASTER,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000 link/ether 00:0f:53:2f:ea:40 brd ff:ff:ff:ff:ff:ff inet6 fe80::20f:53ff:fe2f:ea40/64 scope link valid_lft forever preferred_lft forever (above trimmed to relevant entries, obviously) $ sysctl net.ipv6.conf.ens2f0np0.addr_gen_mode=0 net.ipv6.conf.ens2f0np0.addr_gen_mode = 0 $ sysctl net.ipv6.conf.ens2f1np2.addr_gen_mode=0 net.ipv6.conf.ens2f1np2.addr_gen_mode = 0 $ ip a l ens2f0np0 2: ens2f0np0: <BROADCAST,MULTICAST,SLAVE,UP,LOWER_UP> mtu 1500 qdisc mq master bond0 state UP group default qlen 1000 link/ether 00:0f:53:2f:ea:40 brd ff:ff:ff:ff:ff:ff inet6 fe80::20f:53ff:fe2f:ea40/64 scope link tentative valid_lft forever preferred_lft forever $ ip a l ens2f1np2 5: ens2f1np2: <NO-CARRIER,BROADCAST,MULTICAST,SLAVE,UP> mtu 1500 qdisc mq master bond0 state DOWN group default qlen 1000 link/ether 00:0f:53:2f:ea:40 brd ff:ff:ff:ff:ff:ff inet6 fe80::20f:53ff:fe2f:ea40/64 scope link tentative valid_lft forever preferred_lft forever Looks like addrconf_sysctl_addr_gen_mode() bypasses the original "is this a slave interface?" check added by commit c2edacf80e15, and results in an address getting added, while w/the proposed patch added, no address gets added. This simply adds the same gating check to another code path, and thus should prevent the same devices from erroneously obtaining an ipv6 link-local address. Fixes: d35a00b8e33d ("net/ipv6: allow sysctl to change link-local address generation mode") Reported-by: Moshe Levi <moshele@mellanox.com> CC: Stephen Hemminger <stephen@networkplumber.org> CC: Marcelo Ricardo Leitner <mleitner@redhat.com> CC: netdev@vger.kernel.org Signed-off-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-02vti6: Fix memory leak of skb if input policy check failsTorsten Hilbrich1-1/+1
commit 2a9de3af21aa8c31cd68b0b39330d69f8c1e59df upstream. The vti6_rcv function performs some tests on the retrieved tunnel including checking the IP protocol, the XFRM input policy, the source and destination address. In all but one places the skb is released in the error case. When the input policy check fails the network packet is leaked. Using the same goto-label discard in this case to fix this problem. Fixes: ed1efb2aefbb ("ipv6: Add support for IPsec virtual tunnel interfaces") Signed-off-by: Torsten Hilbrich <torsten.hilbrich@secunet.com> Reviewed-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-02vti[6]: fix packet tx through bpf_redirect() in XinY casesNicolas Dichtel1-7/+25
commit f1ed10264ed6b66b9cd5e8461cffce69be482356 upstream. I forgot the 4in6/6in4 cases in my previous patch. Let's fix them. Fixes: 95224166a903 ("vti[6]: fix packet tx through bpf_redirect()") Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-02Revert "ipv6: Fix handling of LLA with VRF and sockets bound to VRF"Sasha Levin1-2/+1
This reverts commit 0293f8d1bdd21b3eb71032edb5832f9090dea48e. This patch shouldn't have been backported to 4.14. Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-03-20ipv6: restrict IPV6_ADDRFORM operationEric Dumazet1-2/+8
commit b6f6118901d1e867ac9177bbff3b00b185bd4fdc upstream. IPV6_ADDRFORM is able to transform IPv6 socket to IPv4 one. While this operation sounds illogical, we have to support it. One of the things it does for TCP socket is to switch sk->sk_prot to tcp_prot. We now have other layers playing with sk->sk_prot, so we should make sure to not interfere with them. This patch makes sure sk_prot is the default pointer for TCP IPv6 socket. syzbot reported : BUG: kernel NULL pointer dereference, address: 0000000000000000 PGD a0113067 P4D a0113067 PUD a8771067 PMD 0 Oops: 0010 [#1] PREEMPT SMP KASAN CPU: 0 PID: 10686 Comm: syz-executor.0 Not tainted 5.6.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffffc9000281fce0 EFLAGS: 00010246 RAX: 1ffffffff15f48ac RBX: ffffffff8afa4560 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880a69a8f40 RBP: ffffc9000281fd10 R08: ffffffff86ed9b0c R09: ffffed1014d351f5 R10: ffffed1014d351f5 R11: 0000000000000000 R12: ffff8880920d3098 R13: 1ffff1101241a613 R14: ffff8880a69a8f40 R15: 0000000000000000 FS: 00007f2ae75db700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000000a3b85000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: inet_release+0x165/0x1c0 net/ipv4/af_inet.c:427 __sock_release net/socket.c:605 [inline] sock_close+0xe1/0x260 net/socket.c:1283 __fput+0x2e4/0x740 fs/file_table.c:280 ____fput+0x15/0x20 fs/file_table.c:313 task_work_run+0x176/0x1b0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop arch/x86/entry/common.c:164 [inline] prepare_exit_to_usermode+0x480/0x5b0 arch/x86/entry/common.c:195 syscall_return_slowpath+0x113/0x4a0 arch/x86/entry/common.c:278 do_syscall_64+0x11f/0x1c0 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c429 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f2ae75dac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: 0000000000000000 RBX: 00007f2ae75db6d4 RCX: 000000000045c429 RDX: 0000000000000001 RSI: 000000000000011a RDI: 0000000000000004 RBP: 000000000076bf20 R08: 0000000000000038 R09: 0000000000000000 R10: 0000000020000180 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000a9d R14: 00000000004ccfb4 R15: 000000000076bf2c Modules linked in: CR2: 0000000000000000 ---[ end trace 82567b5207e87bae ]--- RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffffc9000281fce0 EFLAGS: 00010246 RAX: 1ffffffff15f48ac RBX: ffffffff8afa4560 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8880a69a8f40 RBP: ffffc9000281fd10 R08: ffffffff86ed9b0c R09: ffffed1014d351f5 R10: ffffed1014d351f5 R11: 0000000000000000 R12: ffff8880920d3098 R13: 1ffff1101241a613 R14: ffff8880a69a8f40 R15: 0000000000000000 FS: 00007f2ae75db700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000000a3b85000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Fixes: 604326b41a6f ("bpf, sockmap: convert to generic sk_msg interface") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot+1938db17e275e85dc328@syzkaller.appspotmail.com Cc: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-20ipv6/addrconf: call ipv6_mc_up() for non-Ethernet interfaceHangbin Liu1-0/+4
[ Upstream commit 60380488e4e0b95e9e82aa68aa9705baa86de84c ] Rafał found an issue that for non-Ethernet interface, if we down and up frequently, the memory will be consumed slowly. The reason is we add allnodes/allrouters addressed in multicast list in ipv6_add_dev(). When link down, we call ipv6_mc_down(), store all multicast addresses via mld_add_delrec(). But when link up, we don't call ipv6_mc_up() for non-Ethernet interface to remove the addresses. This makes idev->mc_tomb getting bigger and bigger. The call stack looks like: addrconf_notify(NETDEV_REGISTER) ipv6_add_dev ipv6_dev_mc_inc(ff01::1) ipv6_dev_mc_inc(ff02::1) ipv6_dev_mc_inc(ff02::2) addrconf_notify(NETDEV_UP) addrconf_dev_config /* Alas, we support only Ethernet autoconfiguration. */ return; addrconf_notify(NETDEV_DOWN) addrconf_ifdown ipv6_mc_down igmp6_group_dropped(ff02::2) mld_add_delrec(ff02::2) igmp6_group_dropped(ff02::1) igmp6_group_dropped(ff01::1) After investigating, I can't found a rule to disable multicast on non-Ethernet interface. In RFC2460, the link could be Ethernet, PPP, ATM, tunnels, etc. In IPv4, it doesn't check the dev type when calls ip_mc_up() in inetdev_event(). Even for IPv6, we don't check the dev type and call ipv6_add_dev(), ipv6_dev_mc_inc() after register device. So I think it's OK to fix this memory consumer by calling ipv6_mc_up() for non-Ethernet interface. v2: Also check IFF_MULTICAST flag to make sure the interface supports multicast Reported-by: Rafał Miłecki <zajec5@gmail.com> Tested-by: Rafał Miłecki <zajec5@gmail.com> Fixes: 74235a25c673 ("[IPV6] addrconf: Fix IPv6 on tuntap tunnels") Fixes: 1666d49e1d41 ("mld: do not remove mld souce list info when set link down") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-11ipv6: Fix route replacement with dev-only routeBenjamin Poirier1-3/+4
[ Upstream commit e404b8c7cfb31654c9024d497cec58a501501692 ] After commit 27596472473a ("ipv6: fix ECMP route replacement") it is no longer possible to replace an ECMP-able route by a non ECMP-able route. For example, ip route add 2001:db8::1/128 via fe80::1 dev dummy0 ip route replace 2001:db8::1/128 dev dummy0 does not work as expected. Tweak the replacement logic so that point 3 in the log of the above commit becomes: 3. If the new route is not ECMP-able, and no matching non-ECMP-able route exists, replace matching ECMP-able route (if any) or add the new route. We can now summarize the entire replace semantics to: When doing a replace, prefer replacing a matching route of the same "ECMP-able-ness" as the replace argument. If there is no such candidate, fallback to the first route found. Fixes: 27596472473a ("ipv6: fix ECMP route replacement") Signed-off-by: Benjamin Poirier <bpoirier@cumulusnetworks.com> Reviewed-by: Michal Kubecek <mkubecek@suse.cz> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-11ipv6: Fix nlmsg_flags when splitting a multipath routeBenjamin Poirier1-0/+1
[ Upstream commit afecdb376bd81d7e16578f0cfe82a1aec7ae18f3 ] When splitting an RTA_MULTIPATH request into multiple routes and adding the second and later components, we must not simply remove NLM_F_REPLACE but instead replace it by NLM_F_CREATE. Otherwise, it may look like the netlink message was malformed. For example, ip route add 2001:db8::1/128 dev dummy0 ip route change 2001:db8::1/128 nexthop via fe80::30:1 dev dummy0 \ nexthop via fe80::30:2 dev dummy0 results in the following warnings: [ 1035.057019] IPv6: RTM_NEWROUTE with no NLM_F_CREATE or NLM_F_REPLACE [ 1035.057517] IPv6: NLM_F_CREATE should be set when creating new route This patch makes the nlmsg sequence look equivalent for __ip6_ins_rt() to what it would get if the multipath route had been added in multiple netlink operations: ip route add 2001:db8::1/128 dev dummy0 ip route change 2001:db8::1/128 nexthop via fe80::30:1 dev dummy0 ip route append 2001:db8::1/128 nexthop via fe80::30:2 dev dummy0 Fixes: 27596472473a ("ipv6: fix ECMP route replacement") Signed-off-by: Benjamin Poirier <bpoirier@cumulusnetworks.com> Reviewed-by: Michal Kubecek <mkubecek@suse.cz> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-05vti[6]: fix packet tx through bpf_redirect()Nicolas Dichtel1-2/+11
[ Upstream commit 95224166a9032ff5d08fca633d37113078ce7d01 ] With an ebpf program that redirects packets through a vti[6] interface, the packets are dropped because no dst is attached. This could also be reproduced with an AF_PACKET socket, with the following python script (vti1 is an ip_vti interface): import socket send_s = socket.socket(socket.AF_PACKET, socket.SOCK_RAW, 0) # scapy # p = IP(src='10.100.0.2', dst='10.200.0.1')/ICMP(type='echo-request') # raw(p) req = b'E\x00\x00\x1c\x00\x01\x00\x00@\x01e\xb2\nd\x00\x02\n\xc8\x00\x01\x08\x00\xf7\xff\x00\x00\x00\x00' send_s.sendto(req, ('vti1', 0x800, 0, 0)) Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-29net, ip6_tunnel: fix namespaces moveWilliam Dauchy1-3/+1
[ Upstream commit 5311a69aaca30fa849c3cc46fb25f75727fb72d0 ] in the same manner as commit d0f418516022 ("net, ip_tunnel: fix namespaces move"), fix namespace moving as it was broken since commit 8d79266bc48c ("ip6_tunnel: add collect_md mode to IPv6 tunnel"), but for ipv6 this time; there is no reason to keep it for ip6_tunnel. Fixes: 8d79266bc48c ("ip6_tunnel: add collect_md mode to IPv6 tunnel") Signed-off-by: William Dauchy <w.dauchy@criteo.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-29ipv6: sr: remove SKB_GSO_IPXIP6 on End.D* actionsYuki Taguchi1-1/+3
[ Upstream commit 62ebaeaedee7591c257543d040677a60e35c7aec ] After LRO/GRO is applied, SRv6 encapsulated packets have SKB_GSO_IPXIP6 feature flag, and this flag must be removed right after decapulation procedure. Currently, SKB_GSO_IPXIP6 flag is not removed on End.D* actions, which creates inconsistent packet state, that is, a normal TCP/IP packets have the SKB_GSO_IPXIP6 flag. This behavior can cause unexpected fallback to GSO on routing to netdevices that do not support SKB_GSO_IPXIP6. For example, on inter-VRF forwarding, decapsulated packets separated into small packets by GSO because VRF devices do not support TSO for packets with SKB_GSO_IPXIP6 flag, and this degrades forwarding performance. This patch removes encapsulation related GSO flags from the skb right after the End.D* action is applied. Fixes: d7a669dd2f8b ("ipv6: sr: add helper functions for seg6local") Signed-off-by: Yuki Taguchi <tagyounit@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-27inet: frags: call inet_frags_fini() after unregister_pernet_subsys()Eric Dumazet1-1/+1
[ Upstream commit ae7352d384a552d8c799c242e74a934809990a71 ] Both IPv6 and 6lowpan are calling inet_frags_fini() too soon. inet_frags_fini() is dismantling a kmem_cache, that might be needed later when unregister_pernet_subsys() eventually has to remove frags queues from hash tables and free them. This fixes potential use-after-free, and is a prereq for the following patch. Fixes: d4ad4d22e7ac ("inet: frags: use kmem_cache for inet_frag_queue") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-04tcp/dccp: fix possible race __inet_lookup_established()Eric Dumazet1-1/+2
commit 8dbd76e79a16b45b2ccb01d2f2e08dbf64e71e40 upstream. Michal Kubecek and Firo Yang did a very nice analysis of crashes happening in __inet_lookup_established(). Since a TCP socket can go from TCP_ESTABLISH to TCP_LISTEN (via a close()/socket()/listen() cycle) without a RCU grace period, I should not have changed listeners linkage in their hash table. They must use the nulls protocol (Documentation/RCU/rculist_nulls.txt), so that a lookup can detect a socket in a hash list was moved in another one. Since we added code in commit d296ba60d8e2 ("soreuseport: Resolve merge conflict for v4/v6 ordering fix"), we have to add hlist_nulls_add_tail_rcu() helper. Fixes: 3b24d854cb35 ("tcp/dccp: do not touch listener sk_refcnt under synflood") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Michal Kubecek <mkubecek@suse.cz> Reported-by: Firo Yang <firo.yang@suse.com> Reviewed-by: Michal Kubecek <mkubecek@suse.cz> Link: https://lore.kernel.org/netdev/20191120083919.GH27852@unicorn.suse.cz/ Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> [stable-4.14: we also need to update code in __inet_lookup_listener() and inet6_lookup_listener() which has been removed in 5.0-rc1.] Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04sit: do not confirm neighbor when do pmtu updateHangbin Liu1-1/+1
[ Upstream commit 4d42df46d6372ece4cb4279870b46c2ea7304a47 ] When do IPv6 tunnel PMTU update and calls __ip6_rt_update_pmtu() in the end, we should not call dst_confirm_neigh() as there is no two-way communication. v5: No change. v4: No change. v3: Do not remove dst_confirm_neigh, but add a new bool parameter in dst_ops.update_pmtu to control whether we should do neighbor confirm. Also split the big patch to small ones for each area. v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu. Reviewed-by: Guillaume Nault <gnault@redhat.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04vti: do not confirm neighbor when do pmtu updateHangbin Liu1-1/+1
[ Upstream commit 8247a79efa2f28b44329f363272550c1738377de ] When do IPv6 tunnel PMTU update and calls __ip6_rt_update_pmtu() in the end, we should not call dst_confirm_neigh() as there is no two-way communication. Although vti and vti6 are immune to this problem because they are IFF_NOARP interfaces, as Guillaume pointed. There is still no sense to confirm neighbour here. v5: Update commit description. v4: No change. v3: Do not remove dst_confirm_neigh, but add a new bool parameter in dst_ops.update_pmtu to control whether we should do neighbor confirm. Also split the big patch to small ones for each area. v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu. Reviewed-by: Guillaume Nault <gnault@redhat.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04tunnel: do not confirm neighbor when do pmtu updateHangbin Liu1-2/+2
[ Upstream commit 7a1592bcb15d71400a98632727791d1e68ea0ee8 ] When do tunnel PMTU update and calls __ip6_rt_update_pmtu() in the end, we should not call dst_confirm_neigh() as there is no two-way communication. v5: No Change. v4: Update commit description v3: Do not remove dst_confirm_neigh, but add a new bool parameter in dst_ops.update_pmtu to control whether we should do neighbor confirm. Also split the big patch to small ones for each area. v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu. Fixes: 0dec879f636f ("net: use dst_confirm_neigh for UDP, RAW, ICMP, L2TP") Reviewed-by: Guillaume Nault <gnault@redhat.com> Tested-by: Guillaume Nault <gnault@redhat.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04ip6_gre: do not confirm neighbor when do pmtu updateHangbin Liu1-1/+1
[ Upstream commit 675d76ad0ad5bf41c9a129772ef0aba8f57ea9a7 ] When we do ipv6 gre pmtu update, we will also do neigh confirm currently. This will cause the neigh cache be refreshed and set to REACHABLE before xmit. But if the remote mac address changed, e.g. device is deleted and recreated, we will not able to notice this and still use the old mac address as the neigh cache is REACHABLE. Fix this by disable neigh confirm when do pmtu update v5: No change. v4: No change. v3: Do not remove dst_confirm_neigh, but add a new bool parameter in dst_ops.update_pmtu to control whether we should do neighbor confirm. Also split the big patch to small ones for each area. v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu. Reported-by: Jianlin Shi <jishi@redhat.com> Reviewed-by: Guillaume Nault <gnault@redhat.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04net: add bool confirm_neigh parameter for dst_ops.update_pmtuHangbin Liu4-11/+20
[ Upstream commit bd085ef678b2cc8c38c105673dfe8ff8f5ec0c57 ] The MTU update code is supposed to be invoked in response to real networking events that update the PMTU. In IPv6 PMTU update function __ip6_rt_update_pmtu() we called dst_confirm_neigh() to update neighbor confirmed time. But for tunnel code, it will call pmtu before xmit, like: - tnl_update_pmtu() - skb_dst_update_pmtu() - ip6_rt_update_pmtu() - __ip6_rt_update_pmtu() - dst_confirm_neigh() If the tunnel remote dst mac address changed and we still do the neigh confirm, we will not be able to update neigh cache and ping6 remote will failed. So for this ip_tunnel_xmit() case, _EVEN_ if the MTU is changed, we should not be invoking dst_confirm_neigh() as we have no evidence of successful two-way communication at this point. On the other hand it is also important to keep the neigh reachability fresh for TCP flows, so we cannot remove this dst_confirm_neigh() call. To fix the issue, we have to add a new bool parameter for dst_ops.update_pmtu to choose whether we should do neigh update or not. I will add the parameter in this patch and set all the callers to true to comply with the previous way, and fix the tunnel code one by one on later patches. v5: No change. v4: No change. v3: Do not remove dst_confirm_neigh, but add a new bool parameter in dst_ops.update_pmtu to control whether we should do neighbor confirm. Also split the big patch to small ones for each area. v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu. Suggested-by: David Miller <davem@davemloft.net> Reviewed-by: Guillaume Nault <gnault@redhat.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-01ipv6: Fix handling of LLA with VRF and sockets bound to VRFDavid Ahern1-1/+2
[ Upstream commit c2027d1e17582903e368abf5d4838b22a98f2b7b ] A recent commit allows sockets bound to a VRF to receive ipv6 link local packets. However, it only works for UDP and worse TCP connection attempts to the LLA with the only listener bound to the VRF just hang where as before the client gets a reset and connection refused. Fix by adjusting ir_iif for LL addresses and packets received through a device enslaved to a VRF. Fixes: 6f12fa775530 ("vrf: mark skb for multicast or link-local as enslaved to VRF") Reported-by: Donald Sharp <sharpd@cumulusnetworks.com> Cc: Mike Manning <mmanning@vyatta.att-mail.com> Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-20netfilter: masquerade: don't flush all conntracks if only one address ↵Tan Hu1-3/+16
deleted on device [ Upstream commit 097f95d319f817e651bd51f8846aced92a55a6a1 ] We configured iptables as below, which only allowed incoming data on established connections: iptables -t mangle -A PREROUTING -m state --state ESTABLISHED -j ACCEPT iptables -t mangle -P PREROUTING DROP When deleting a secondary address, current masquerade implements would flush all conntracks on this device. All the established connections on primary address also be deleted, then subsequent incoming data on the connections would be dropped wrongly because it was identified as NEW connection. So when an address was delete, it should only flush connections related with the address. Signed-off-by: Tan Hu <tan.hu@zte.com.cn> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-10net: annotate accesses to sk->sk_incoming_cpuEric Dumazet2-2/+2
[ Upstream commit 7170a977743b72cf3eb46ef6ef89885dc7ad3621 ] This socket field can be read and written by concurrent cpus. Use READ_ONCE() and WRITE_ONCE() annotations to document this, and avoid some compiler 'optimizations'. KCSAN reported : BUG: KCSAN: data-race in tcp_v4_rcv / tcp_v4_rcv write to 0xffff88812220763c of 4 bytes by interrupt on cpu 0: sk_incoming_cpu_update include/net/sock.h:953 [inline] tcp_v4_rcv+0x1b3c/0x1bb0 net/ipv4/tcp_ipv4.c:1934 ip_protocol_deliver_rcu+0x4d/0x420 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5124 process_backlog+0x1d3/0x420 net/core/dev.c:5955 napi_poll net/core/dev.c:6392 [inline] net_rx_action+0x3ae/0xa90 net/core/dev.c:6460 __do_softirq+0x115/0x33f kernel/softirq.c:292 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1082 do_softirq.part.0+0x6b/0x80 kernel/softirq.c:337 do_softirq kernel/softirq.c:329 [inline] __local_bh_enable_ip+0x76/0x80 kernel/softirq.c:189 read to 0xffff88812220763c of 4 bytes by interrupt on cpu 1: sk_incoming_cpu_update include/net/sock.h:952 [inline] tcp_v4_rcv+0x181a/0x1bb0 net/ipv4/tcp_ipv4.c:1934 ip_protocol_deliver_rcu+0x4d/0x420 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5124 process_backlog+0x1d3/0x420 net/core/dev.c:5955 napi_poll net/core/dev.c:6392 [inline] net_rx_action+0x3ae/0xa90 net/core/dev.c:6460 __do_softirq+0x115/0x33f kernel/softirq.c:292 run_ksoftirqd+0x46/0x60 kernel/softirq.c:603 smpboot_thread_fn+0x37d/0x4a0 kernel/smpboot.c:165 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-07ipv6: Handle missing host route in __ipv6_ifa_notifyDavid Ahern1-5/+12
[ Upstream commit 2d819d250a1393a3e725715425ab70a0e0772a71 ] Rajendra reported a kernel panic when a link was taken down: [ 6870.263084] BUG: unable to handle kernel NULL pointer dereference at 00000000000000a8 [ 6870.271856] IP: [<ffffffff8efc5764>] __ipv6_ifa_notify+0x154/0x290 <snip> [ 6870.570501] Call Trace: [ 6870.573238] [<ffffffff8efc58c6>] ? ipv6_ifa_notify+0x26/0x40 [ 6870.579665] [<ffffffff8efc98ec>] ? addrconf_dad_completed+0x4c/0x2c0 [ 6870.586869] [<ffffffff8efe70c6>] ? ipv6_dev_mc_inc+0x196/0x260 [ 6870.593491] [<ffffffff8efc9c6a>] ? addrconf_dad_work+0x10a/0x430 [ 6870.600305] [<ffffffff8f01ade4>] ? __switch_to_asm+0x34/0x70 [ 6870.606732] [<ffffffff8ea93a7a>] ? process_one_work+0x18a/0x430 [ 6870.613449] [<ffffffff8ea93d6d>] ? worker_thread+0x4d/0x490 [ 6870.619778] [<ffffffff8ea93d20>] ? process_one_work+0x430/0x430 [ 6870.626495] [<ffffffff8ea99dd9>] ? kthread+0xd9/0xf0 [ 6870.632145] [<ffffffff8f01ade4>] ? __switch_to_asm+0x34/0x70 [ 6870.638573] [<ffffffff8ea99d00>] ? kthread_park+0x60/0x60 [ 6870.644707] [<ffffffff8f01ae77>] ? ret_from_fork+0x57/0x70 [ 6870.650936] Code: 31 c0 31 d2 41 b9 20 00 08 02 b9 09 00 00 0 addrconf_dad_work is kicked to be scheduled when a device is brought up. There is a race between addrcond_dad_work getting scheduled and taking the rtnl lock and a process taking the link down (under rtnl). The latter removes the host route from the inet6_addr as part of addrconf_ifdown which is run for NETDEV_DOWN. The former attempts to use the host route in __ipv6_ifa_notify. If the down event removes the host route due to the race to the rtnl, then the BUG listed above occurs. Since the DAD sequence can not be aborted, add a check for the missing host route in __ipv6_ifa_notify. The only way this should happen is due to the previously mentioned race. The host route is created when the address is added to an interface; it is only removed on a down event where the address is kept. Add a warning if the host route is missing AND the device is up; this is a situation that should never happen. Fixes: f1705ec197e7 ("net: ipv6: Make address flushing on ifdown optional") Reported-by: Rajendra Dendukuri <rajendra.dendukuri@broadcom.com> Signed-off-by: David Ahern <dsahern@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-07ipv6: drop incoming packets having a v4mapped source addressEric Dumazet1-0/+10
[ Upstream commit 6af1799aaf3f1bc8defedddfa00df3192445bbf3 ] This began with a syzbot report. syzkaller was injecting IPv6 TCP SYN packets having a v4mapped source address. After an unsuccessful 4-tuple lookup, TCP creates a request socket (SYN_RECV) and calls reqsk_queue_hash_req() reqsk_queue_hash_req() calls sk_ehashfn(sk) At this point we have AF_INET6 sockets, and the heuristic used by sk_ehashfn() to either hash the IPv4 or IPv6 addresses is to use ipv6_addr_v4mapped(&sk->sk_v6_daddr) For the particular spoofed packet, we end up hashing V4 addresses which were not initialized by the TCP IPv6 stack, so KMSAN fired a warning. I first fixed sk_ehashfn() to test both source and destination addresses, but then faced various problems, including user-space programs like packetdrill that had similar assumptions. Instead of trying to fix the whole ecosystem, it is better to admit that we have a dual stack behavior, and that we can not build linux kernels without V4 stack anyway. The dual stack API automatically forces the traffic to be IPv4 if v4mapped addresses are used at bind() or connect(), so it makes no sense to allow IPv6 traffic to use the same v4mapped class. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Florian Westphal <fw@strlen.de> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-19ipv6: Fix the link time qualifier of 'ping_v6_proc_exit_net()'Christophe JAILLET1-1/+1
[ Upstream commit d23dbc479a8e813db4161a695d67da0e36557846 ] The '.exit' functions from 'pernet_operations' structure should be marked as __net_exit, not __net_init. Fixes: d862e5461423 ("net: ipv6: Implement /proc/net/icmp6.") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-10mld: fix memory leak in mld_del_delrec()Eric Dumazet1-2/+3
[ Upstream commit a84d016479896b5526a2cc54784e6ffc41c9d6f6 ] Similar to the fix done for IPv4 in commit e5b1c6c6277d ("igmp: fix memory leak in igmpv3_del_delrec()"), we need to make sure mca_tomb and mca_sources are not blindly overwritten. Using swap() then a call to ip6_mc_clear_src() will take care of the missing free. BUG: memory leak unreferenced object 0xffff888117d9db00 (size 64): comm "syz-executor247", pid 6918, jiffies 4294943989 (age 25.350s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 fe 88 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<000000005b463030>] kmemleak_alloc_recursive include/linux/kmemleak.h:43 [inline] [<000000005b463030>] slab_post_alloc_hook mm/slab.h:522 [inline] [<000000005b463030>] slab_alloc mm/slab.c:3319 [inline] [<000000005b463030>] kmem_cache_alloc_trace+0x145/0x2c0 mm/slab.c:3548 [<00000000939cbf94>] kmalloc include/linux/slab.h:552 [inline] [<00000000939cbf94>] kzalloc include/linux/slab.h:748 [inline] [<00000000939cbf94>] ip6_mc_add1_src net/ipv6/mcast.c:2236 [inline] [<00000000939cbf94>] ip6_mc_add_src+0x31f/0x420 net/ipv6/mcast.c:2356 [<00000000d8972221>] ip6_mc_source+0x4a8/0x600 net/ipv6/mcast.c:449 [<000000002b203d0d>] do_ipv6_setsockopt.isra.0+0x1b92/0x1dd0 net/ipv6/ipv6_sockglue.c:748 [<000000001f1e2d54>] ipv6_setsockopt+0x89/0xd0 net/ipv6/ipv6_sockglue.c:944 [<00000000c8f7bdf9>] udpv6_setsockopt+0x4e/0x90 net/ipv6/udp.c:1558 [<000000005a9a0c5e>] sock_common_setsockopt+0x38/0x50 net/core/sock.c:3139 [<00000000910b37b2>] __sys_setsockopt+0x10f/0x220 net/socket.c:2084 [<00000000e9108023>] __do_sys_setsockopt net/socket.c:2100 [inline] [<00000000e9108023>] __se_sys_setsockopt net/socket.c:2097 [inline] [<00000000e9108023>] __x64_sys_setsockopt+0x26/0x30 net/socket.c:2097 [<00000000f4818160>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:296 [<000000008d367e8f>] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 1666d49e1d41 ("mld: do not remove mld souce list info when set link down") Fixes: 9c8bb163ae78 ("igmp, mld: Fix memory leak in igmpv3/mld_del_delrec()") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-16netfilter: Fix rpfilter dropping vrf packets by mistakeMiaohe Lin1-2/+6
[ Upstream commit b575b24b8eee37f10484e951b62ce2a31c579775 ] When firewalld is enabled with ipv4/ipv6 rpfilter, vrf ipv4/ipv6 packets will be dropped. Vrf device will pass through netfilter hook twice. One with enslaved device and another one with l3 master device. So in device may dismatch witch out device because out device is always enslaved device.So failed with the check of the rpfilter and drop the packets by mistake. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-08-09ip6_tunnel: fix possible use-after-free on xmitHaishuang Yan1-4/+2
[ Upstream commit 01f5bffad555f8e22a61f4b1261fe09cf1b96994 ] ip4ip6/ip6ip6 tunnels run iptunnel_handle_offloads on xmit which can cause a possible use-after-free accessing iph/ipv6h pointer since the packet will be 'uncloned' running pskb_expand_head if it is a cloned gso skb. Fixes: 0e9a709560db ("ip6_tunnel, ip6_gre: fix setting of DSCP on encapsulated packets") Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-21netfilter: ipv6: nf_defrag: accept duplicate fragments againGuillaume Nault1-3/+7
[ Upstream commit 8a3dca632538c550930ce8bafa8c906b130d35cf ] When fixing the skb leak introduced by the conversion to rbtree, I forgot about the special case of duplicate fragments. The condition under the 'insert_error' label isn't effective anymore as nf_ct_frg6_gather() doesn't override the returned value anymore. So duplicate fragments now get NF_DROP verdict. To accept duplicate fragments again, handle them specially as soon as inet_frag_queue_insert() reports them. Return -EINPROGRESS which will translate to NF_STOLEN verdict, like any accepted fragment. However, such packets don't carry any new information and aren't queued, so we just drop them immediately. Fixes: a0d56cb911ca ("netfilter: ipv6: nf_defrag: fix leakage of unqueued fragments") Signed-off-by: Guillaume Nault <gnault@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-21netfilter: ipv6: nf_defrag: fix leakage of unqueued fragmentsGuillaume Nault1-7/+5
[ Upstream commit a0d56cb911ca301de81735f1d73c2aab424654ba ] With commit 997dd9647164 ("net: IP6 defrag: use rbtrees in nf_conntrack_reasm.c"), nf_ct_frag6_reasm() is now called from nf_ct_frag6_queue(). With this change, nf_ct_frag6_queue() can fail after the skb has been added to the fragment queue and nf_ct_frag6_gather() was adapted to handle this case. But nf_ct_frag6_queue() can still fail before the fragment has been queued. nf_ct_frag6_gather() can't handle this case anymore, because it has no way to know if nf_ct_frag6_queue() queued the fragment before failing. If it didn't, the skb is lost as the error code is overwritten with -EINPROGRESS. Fix this by setting -EINPROGRESS directly in nf_ct_frag6_queue(), so that nf_ct_frag6_gather() can propagate the error as is. Fixes: 997dd9647164 ("net: IP6 defrag: use rbtrees in nf_conntrack_reasm.c") Signed-off-by: Guillaume Nault <gnault@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-03bpf: udp: ipv6: Avoid running reuseport's bpf_prog from __udp6_lib_errMartin KaFai Lau1-1/+1
commit 4ac30c4b3659efac031818c418beb51e630d512d upstream. __udp6_lib_err() may be called when handling icmpv6 message. For example, the icmpv6 toobig(type=2). __udp6_lib_lookup() is then called which may call reuseport_select_sock(). reuseport_select_sock() will call into a bpf_prog (if there is one). reuseport_select_sock() is expecting the skb->data pointing to the transport header (udphdr in this case). For example, run_bpf_filter() is pulling the transport header. However, in the __udp6_lib_err() path, the skb->data is pointing to the ipv6hdr instead of the udphdr. One option is to pull and push the ipv6hdr in __udp6_lib_err(). Instead of doing this, this patch follows how the original commit 538950a1b752 ("soreuseport: setsockopt SO_ATTACH_REUSEPORT_[CE]BPF") was done in IPv4, which has passed a NULL skb pointer to reuseport_select_sock(). Fixes: 538950a1b752 ("soreuseport: setsockopt SO_ATTACH_REUSEPORT_[CE]BPF") Cc: Craig Gallek <kraig@google.com> Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Acked-by: Craig Gallek <kraig@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-03bpf: udp: Avoid calling reuseport's bpf_prog from udp_groMartin KaFai Lau1-1/+1
commit 257a525fe2e49584842c504a92c27097407f778f upstream. When the commit a6024562ffd7 ("udp: Add GRO functions to UDP socket") added udp[46]_lib_lookup_skb to the udp_gro code path, it broke the reuseport_select_sock() assumption that skb->data is pointing to the transport header. This patch follows an earlier __udp6_lib_err() fix by passing a NULL skb to avoid calling the reuseport's bpf_prog. Fixes: a6024562ffd7 ("udp: Add GRO functions to UDP socket") Cc: Tom Herbert <tom@herbertland.com> Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-22ipv6: flowlabel: fl6_sock_lookup() must use atomic_inc_not_zeroEric Dumazet1-3/+4
[ Upstream commit 65a3c497c0e965a552008db8bc2653f62bc925a1 ] Before taking a refcount, make sure the object is not already scheduled for deletion. Same fix is needed in ipv6_flowlabel_opt() Fixes: 18367681a10b ("ipv6 flowlabel: Convert np->ipv6_fl_list to RCU.") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-11ipv6: use READ_ONCE() for inet->hdrincl as in ipv4Olivier Matz1-2/+10
[ Upstream commit 59e3e4b52663a9d97efbce7307f62e4bc5c9ce91 ] As it was done in commit 8f659a03a0ba ("net: ipv4: fix for a race condition in raw_sendmsg") and commit 20b50d79974e ("net: ipv4: emulate READ_ONCE() on ->hdrincl bit-field in raw_sendmsg()") for ipv4, copy the value of inet->hdrincl in a local variable, to avoid introducing a race condition in the next commit. Signed-off-by: Olivier Matz <olivier.matz@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-11ipv6: fix EFAULT on sendto with icmpv6 and hdrinclOlivier Matz1-5/+8
[ Upstream commit b9aa52c4cb457e7416cc0c95f475e72ef4a61336 ] The following code returns EFAULT (Bad address): s = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6); setsockopt(s, SOL_IPV6, IPV6_HDRINCL, 1); sendto(ipv6_icmp6_packet, addr); /* returns -1, errno = EFAULT */ The IPv4 equivalent code works. A workaround is to use IPPROTO_RAW instead of IPPROTO_ICMPV6. The failure happens because 2 bytes are eaten from the msghdr by rawv6_probe_proto_opt() starting from commit 19e3c66b52ca ("ipv6 equivalent of "ipv4: Avoid reading user iov twice after raw_probe_proto_opt""), but at that time it was not a problem because IPV6_HDRINCL was not yet introduced. Only eat these 2 bytes if hdrincl == 0. Fixes: 715f504b1189 ("ipv6: add IPV6_HDRINCL option for raw sockets") Signed-off-by: Olivier Matz <olivier.matz@6wind.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-09ipv6: Consider sk_bound_dev_if when binding a raw socket to an addressMike Manning1-0/+2
[ Upstream commit 72f7cfab6f93a8ea825fab8ccfb016d064269f7f ] IPv6 does not consider if the socket is bound to a device when binding to an address. The result is that a socket can be bound to eth0 and then bound to the address of eth1. If the device is a VRF, the result is that a socket can only be bound to an address in the default VRF. Resolve by considering the device if sk_bound_dev_if is set. Signed-off-by: Mike Manning <mmanning@vyatta.att-mail.com> Reviewed-by: David Ahern <dsahern@gmail.com> Tested-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-09inet: switch IP ID generator to siphashEric Dumazet1-14/+16
[ Upstream commit df453700e8d81b1bdafdf684365ee2b9431fb702 ] According to Amit Klein and Benny Pinkas, IP ID generation is too weak and might be used by attackers. Even with recent net_hash_mix() fix (netns: provide pure entropy for net_hash_mix()) having 64bit key and Jenkins hash is risky. It is time to switch to siphash and its 128bit keys. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Amit Klein <aksecurity@gmail.com> Reported-by: Benny Pinkas <benny@pinkas.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-25xfrm6_tunnel: Fix potential panic when unloading xfrm6_tunnel moduleSu Yanjun1-0/+4
[ Upstream commit 6ee02a54ef990a71bf542b6f0a4e3321de9d9c66 ] When unloading xfrm6_tunnel module, xfrm6_tunnel_fini directly frees the xfrm6_tunnel_spi_kmem. Maybe someone has gotten the xfrm6_tunnel_spi, so need to wait it. Fixes: 91cc3bb0b04ff("xfrm6_tunnel: RCU conversion") Signed-off-by: Su Yanjun <suyj.fnst@cn.fujitsu.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-16vrf: sit mtu should not be updated when vrf netdev is the linkStephen Suryaputra1-1/+1
[ Upstream commit ff6ab32bd4e073976e4d8797b4d514a172cfe6cb ] VRF netdev mtu isn't typically set and have an mtu of 65536. When the link of a tunnel is set, the tunnel mtu is changed from 1480 to the link mtu minus tunnel header. In the case of VRF netdev is the link, then the tunnel mtu becomes 65516. So, fix it by not setting the tunnel mtu in this case. Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-08ipv6: invert flowlabel sharing check in process and user modeWillem de Bruijn1-2/+2
[ Upstream commit 95c169251bf734aa555a1e8043e4d88ec97a04ec ] A request for a flowlabel fails in process or user exclusive mode must fail if the caller pid or uid does not match. Invert the test. Previously, the test was unsafe wrt PID recycling, but indeed tested for inequality: fl1->owner != fl->owner Fixes: 4f82f45730c68 ("net ip6 flowlabel: Make owner a union of struct pid* and kuid_t") Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>