starfive-tech/linux.git/net/ipv6, branch visionfive_v1_5.13

ipv6: ip6_finish_output2: set sk into newly allocated nskb

2021-07-31T06:13:47+00:00

[ Upstream commit 2d85a1b31dde84038ea07ad825c3d8d3e71f4344 ] skb_set_owner_w() should set sk not to old skb but to new nskb. Fixes: 5796015fa968 ("ipv6: allocate enough headroom in ip6_finish_output2()") Signed-off-by: Vasily Averin Link: https://lore.kernel.org/r/70c0744f-89ae-1869-7e3e-4fa292158f4b@virtuozzo.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

ipv6: allocate enough headroom in ip6_finish_output2()

2021-07-31T06:13:46+00:00

[ Upstream commit 5796015fa968a3349027a27dcd04c71d95c53ba5 ] When TEE target mirrors traffic to another interface, sk_buff may not have enough headroom to be processed correctly. ip_finish_output2() detect this situation for ipv4 and allocates new skb with enogh headroom. However ipv6 lacks this logic in ip_finish_output2 and it leads to skb_under_panic: skbuff: skb_under_panic: text:ffffffffc0866ad4 len:96 put:24 head:ffff97be85e31800 data:ffff97be85e317f8 tail:0x58 end:0xc0 dev:gre0 ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:110! invalid opcode: 0000 [#1] SMP PTI CPU: 2 PID: 393 Comm: kworker/2:2 Tainted: G OE 5.13.0 #13 Hardware name: Virtuozzo KVM, BIOS 1.11.0-2.vz7.4 04/01/2014 Workqueue: ipv6_addrconf addrconf_dad_work RIP: 0010:skb_panic+0x48/0x4a Call Trace: skb_push.cold.111+0x10/0x10 ipgre_header+0x24/0xf0 [ip_gre] neigh_connected_output+0xae/0xf0 ip6_finish_output2+0x1a8/0x5a0 ip6_output+0x5c/0x110 nf_dup_ipv6+0x158/0x1000 [nf_dup_ipv6] tee_tg6+0x2e/0x40 [xt_TEE] ip6t_do_table+0x294/0x470 [ip6_tables] nf_hook_slow+0x44/0xc0 nf_hook.constprop.34+0x72/0xe0 ndisc_send_skb+0x20d/0x2e0 ndisc_send_ns+0xd1/0x210 addrconf_dad_work+0x3c8/0x540 process_one_work+0x1d1/0x370 worker_thread+0x30/0x390 kthread+0x116/0x130 ret_from_fork+0x22/0x30 Signed-off-by: Vasily Averin Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

udp: check encap socket in __udp_lib_err

2021-07-28T12:37:33+00:00

[ Upstream commit 9bfce73c8921c92a9565562e6e7d458d37b7ce80 ] Commit d26796ae5894 ("udp: check udp sock encap_type in __udp_lib_err") added checks for encapsulated sockets but it broke cases when there is no implementation of encap_err_lookup for encapsulation, i.e. ESP in UDP encapsulation. Fix it by calling encap_err_lookup only if socket implements this method otherwise treat it as legal socket. Fixes: d26796ae5894 ("udp: check udp sock encap_type in __udp_lib_err") Signed-off-by: Vadim Fedorenko Reviewed-by: Xin Long Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

ipv6: fix another slab-out-of-bounds in fib6_nh_flush_exceptions

2021-07-28T12:37:31+00:00

[ Upstream commit 8fb4792f091e608a0a1d353dfdf07ef55a719db5 ] While running the self-tests on a KASAN enabled kernel, I observed a slab-out-of-bounds splat very similar to the one reported in commit 821bbf79fe46 ("ipv6: Fix KASAN: slab-out-of-bounds Read in fib6_nh_flush_exceptions"). We additionally need to take care of fib6_metrics initialization failure when the caller provides an nh. The fix is similar, explicitly free the route instead of calling fib6_info_release on a half-initialized object. Fixes: f88d8ea67fbdb ("ipv6: Plumb support for nexthop object in a fib6_info") Signed-off-by: Paolo Abeni Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

ipv6: fix 'disable_policy' for fwd packets

2021-07-28T12:37:22+00:00

[ Upstream commit ccd27f05ae7b8ebc40af5b004e94517a919aa862 ] The goal of commit df789fe75206 ("ipv6: Provide ipv6 version of "disable_policy" sysctl") was to have the disable_policy from ipv4 available on ipv6. However, it's not exactly the same mechanism. On IPv4, all packets coming from an interface, which has disable_policy set, bypass the policy check. For ipv6, this is done only for local packets, ie for packets destinated to an address configured on the incoming interface. Let's align ipv6 with ipv4 so that the 'disable_policy' sysctl has the same effect for both protocols. My first approach was to create a new kind of route cache entries, to be able to set DST_NOPOLICY without modifying routes. This would have added a lot of code. Because the local delivery path is already handled, I choose to focus on the forwarding path to minimize code churn. Fixes: df789fe75206 ("ipv6: Provide ipv6 version of "disable_policy" sysctl") Signed-off-by: Nicolas Dichtel Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

udp: annotate data races around unix_sk(sk)->gso_size

2021-07-25T12:37:37+00:00

commit 18a419bad63b7f68a1979e28459782518e7b6bbe upstream. Accesses to unix_sk(sk)->gso_size are lockless. Add READ_ONCE()/WRITE_ONCE() around them. BUG: KCSAN: data-race in udp_lib_setsockopt / udpv6_sendmsg write to 0xffff88812d78f47c of 2 bytes by task 10849 on cpu 1: udp_lib_setsockopt+0x3b3/0x710 net/ipv4/udp.c:2696 udpv6_setsockopt+0x63/0x90 net/ipv6/udp.c:1630 sock_common_setsockopt+0x5d/0x70 net/core/sock.c:3265 __sys_setsockopt+0x18f/0x200 net/socket.c:2104 __do_sys_setsockopt net/socket.c:2115 [inline] __se_sys_setsockopt net/socket.c:2112 [inline] __x64_sys_setsockopt+0x62/0x70 net/socket.c:2112 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff88812d78f47c of 2 bytes by task 10852 on cpu 0: udpv6_sendmsg+0x161/0x16b0 net/ipv6/udp.c:1299 inet6_sendmsg+0x5f/0x80 net/ipv6/af_inet6.c:642 sock_sendmsg_nosec net/socket.c:654 [inline] sock_sendmsg net/socket.c:674 [inline] ____sys_sendmsg+0x360/0x4d0 net/socket.c:2337 ___sys_sendmsg net/socket.c:2391 [inline] __sys_sendmmsg+0x315/0x4b0 net/socket.c:2477 __do_sys_sendmmsg net/socket.c:2506 [inline] __se_sys_sendmmsg net/socket.c:2503 [inline] __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2503 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x0000 -> 0x0005 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 10852 Comm: syz-executor.0 Not tainted 5.13.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: bec1f6f69736 ("udp: generate gso with UDP_SEGMENT") Signed-off-by: Eric Dumazet Cc: Willem de Bruijn Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv6: tcp: drop silly ICMPv6 packet too big messages

2021-07-25T12:37:36+00:00

commit c7bb4b89033b764eb07db4e060548a6311d801ee upstream. While TCP stack scales reasonably well, there is still one part that can be used to DDOS it. IPv6 Packet too big messages have to lookup/insert a new route, and if abused by attackers, can easily put hosts under high stress, with many cpus contending on a spinlock while one is stuck in fib6_run_gc() ip6_protocol_deliver_rcu() icmpv6_rcv() icmpv6_notify() tcp_v6_err() tcp_v6_mtu_reduced() inet6_csk_update_pmtu() ip6_rt_update_pmtu() __ip6_rt_update_pmtu() ip6_rt_cache_alloc() ip6_dst_alloc() dst_alloc() ip6_dst_gc() fib6_run_gc() spin_lock_bh() ... Some of our servers have been hit by malicious ICMPv6 packets trying to _increase_ the MTU/MSS of TCP flows. We believe these ICMPv6 packets are a result of a bug in one ISP stack, since they were blindly sent back for _every_ (small) packet sent to them. These packets are for one TCP flow: 09:24:36.266491 IP6 Addr1 > Victim ICMP6, packet too big, mtu 1460, length 1240 09:24:36.266509 IP6 Addr1 > Victim ICMP6, packet too big, mtu 1460, length 1240 09:24:36.316688 IP6 Addr1 > Victim ICMP6, packet too big, mtu 1460, length 1240 09:24:36.316704 IP6 Addr1 > Victim ICMP6, packet too big, mtu 1460, length 1240 09:24:36.608151 IP6 Addr1 > Victim ICMP6, packet too big, mtu 1460, length 1240 TCP stack can filter some silly requests : 1) MTU below IPV6_MIN_MTU can be filtered early in tcp_v6_err() 2) tcp_v6_mtu_reduced() can drop requests trying to increase current MSS. This tests happen before the IPv6 routing stack is entered, thus removing the potential contention and route exhaustion. Note that IPv6 stack was performing these checks, but too late (ie : after the route has been added, and after the potential garbage collect war) v2: fix typo caught by Martin, thanks ! v3: exports tcp_mtu_to_mss(), caught by David, thanks ! Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet Reviewed-by: Maciej Żenczykowski Cc: Martin KaFai Lau Acked-by: Martin KaFai Lau Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tcp: annotate data races around tp->mtu_info

2021-07-25T12:37:36+00:00

commit 561022acb1ce62e50f7a8258687a21b84282a4cb upstream. While tp->mtu_info is read while socket is owned, the write sides happen from err handlers (tcp_v[46]_mtu_reduced) which only own the socket spinlock. Fixes: 563d34d05786 ("tcp: dont drop MTU reduction indications") Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: send SYNACK packet with accepted fwmark

2021-07-25T12:37:34+00:00

commit 43b90bfad34bcb81b8a5bc7dc650800f4be1787e upstream. commit e05a90ec9e16 ("net: reflect mark on tcp syn ack packets") fixed IPv4 only. This part is for the IPv6 side. Fixes: e05a90ec9e16 ("net: reflect mark on tcp syn ack packets") Signed-off-by: Alexander Ovechkin Acked-by: Dmitry Yakunin Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: ipv6: fix return value of ip6_skb_dst_mtu

2021-07-25T12:37:33+00:00

commit 40fc3054b45820c28ea3c65e2c86d041dc244a8a upstream. Commit 628a5c561890 ("[INET]: Add IP(V6)_PMTUDISC_RPOBE") introduced ip6_skb_dst_mtu with return value of signed int which is inconsistent with actually returned values. Also 2 users of this function actually assign its value to unsigned int variable and only __xfrm6_output assigns result of this function to signed variable but actually uses as unsigned in further comparisons and calls. Change this function to return unsigned int value. Fixes: 628a5c561890 ("[INET]: Add IP(V6)_PMTUDISC_RPOBE") Reviewed-by: David Ahern Signed-off-by: Vadim Fedorenko Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman