linux/net/ipv4
Willem de Bruijn 730c54d594 ipv4: remove warning in ip_recv_error
A precondition check in ip_recv_error triggered on an otherwise benign
race. Remove the warning.

The warning triggers when passing an ipv6 socket to this ipv4 error
handling function. RaceFuzzer was able to trigger it due to a race
in setsockopt IPV6_ADDRFORM.

  ---
  CPU0
    do_ipv6_setsockopt
      sk->sk_socket->ops = &inet_dgram_ops;

  ---
  CPU1
    sk->sk_prot->recvmsg
      udp_recvmsg
        ip_recv_error
          WARN_ON_ONCE(sk->sk_family == AF_INET6);

  ---
  CPU0
    do_ipv6_setsockopt
      sk->sk_family = PF_INET;

This socket option converts a v6 socket that is connected to a v4 peer
to an v4 socket. It updates the socket on the fly, changing fields in
sk as well as other structs. This is inherently non-atomic. It races
with the lockless udp_recvmsg path.

No other code makes an assumption that these fields are updated
atomically. It is benign here, too, as ip_recv_error cares only about
the protocol of the skbs enqueued on the error queue, for which
sk_family is not a precise predictor (thanks to another isue with
IPV6_ADDRFORM).

Link: http://lkml.kernel.org/r/20180518120826.GA19515@dragonet.kaist.ac.kr
Fixes: 7ce875e5ec ("ipv4: warn once on passing AF_INET6 socket to ip_recv_error")
Reported-by: DaeRyong Jeong <threeearcat@gmail.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-24 22:16:57 -04:00
..
netfilter net/ipv4: Initialize proto and ports in flow struct 2018-05-17 14:55:21 -04:00
Kconfig ipmr,ipmr6: Define a uniform vif_device 2018-03-01 13:13:23 -05:00
Makefile ipmr,ipmr6: Define a uniform vif_device 2018-03-01 13:13:23 -05:00
af_inet.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2018-03-31 23:33:04 -04:00
ah4.c net: use -ENOSPC for transient busy indication 2017-11-03 22:11:17 +08:00
arp.c arp: fix arp_filter on l3slave devices 2018-04-05 22:05:03 -04:00
cipso_ipv4.c tcp/dccp: fix ireq->opt races 2017-10-21 01:33:19 +01:00
datagram.c
devinet.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
esp4.c esp4: remove redundant initialization of pointer esph 2018-02-13 13:59:03 +01:00
esp4_offload.c esp: check the NETIF_F_HW_ESP_TX_CSUM bit before segmenting 2018-02-27 10:46:01 +01:00
fib_frontend.c net: ipv4: add missing RTA_TABLE to rtm_ipv4_policy 2018-05-23 15:03:28 -04:00
fib_lookup.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
fib_notifier.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
fib_rules.c ipv6: route: dissect flow in input path if fib rules need it 2018-02-28 22:44:44 -05:00
fib_semantics.c route: check sysctl_fib_multipath_use_neigh earlier than hash 2018-04-01 20:57:39 -04:00
fib_trie.c net/ipv4: Allow notifier to fail route replace 2018-03-29 14:10:30 -04:00
fou.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
gre_demux.c
gre_offload.c gso: fix payload length when gso_size is zero 2017-10-08 10:12:15 -07:00
icmp.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
igmp.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
inet_connection_sock.c Revert "defer call to mem_cgroup_sk_alloc()" 2018-02-02 19:49:31 -05:00
inet_diag.c sock_diag: request _diag module only when the family or proto has been registered 2018-03-12 11:03:42 -04:00
inet_fragment.c inet: frags: remove inet_frag_maybe_warn_overflow() 2018-03-31 23:25:39 -04:00
inet_hashtables.c inet: Avoid unitialized variable warning in inet_unhash() 2018-02-01 09:48:42 -05:00
inet_timewait_sock.c soreuseport: initialise timewait reuseport field 2018-04-07 22:32:32 -04:00
inetpeer.c inetpeer: fix uninit-value in inet_getpeer 2018-04-09 10:57:35 -04:00
ip_forward.c net: rename skb_gso_validate_mtu -> skb_gso_validate_network_len 2018-03-04 17:49:17 -05:00
ip_fragment.c inet: frags: fix ip6frag_low_thresh boundary 2018-04-04 12:04:59 -04:00
ip_gre.c erspan: fix invalid erspan version. 2018-05-17 15:48:49 -04:00
ip_input.c net: Make ip_ra_chain per struct net 2018-03-22 15:12:56 -04:00
ip_options.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ip_output.c net: test tailroom before appending to linear skb 2018-05-17 17:05:01 -04:00
ip_sockglue.c ipv4: remove warning in ip_recv_error 2018-05-24 22:16:57 -04:00
ip_tunnel.c ip_tunnel: better validate user provided tunnel names 2018-04-05 15:16:15 -04:00
ip_tunnel_core.c net: store port/representator id in metadata_dst 2017-06-25 11:42:01 -04:00
ip_vti.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
ipcomp.c
ipconfig.c net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
ipip.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
ipmr.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
ipmr_base.c ipmr: properly check rhltable_init() return value 2018-05-22 15:31:15 -04:00
netfilter.c netfilter: remove struct nf_afinfo and its helper functions 2018-01-08 18:11:02 +01:00
ping.c ipv4: fix memory leaks in udp_sendmsg, ping_v4_sendmsg 2018-05-11 12:00:58 -04:00
proc.c inet: frags: break the 2GB limit for frags storage 2018-03-31 23:25:39 -04:00
protocol.c net: Add sysctl to toggle early demux for tcp and udp 2017-03-24 13:17:07 -07:00
raw.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
raw_diag.c net: ipv6: add second dif to raw socket lookups 2017-08-07 11:39:22 -07:00
route.c net/ipv4: Initialize proto and ports in flow struct 2018-05-17 14:55:21 -04:00
syncookies.c net/ipv4: disable SMC TCP option with SYN Cookies 2018-03-25 20:53:54 -04:00
sysctl_net_ipv4.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
tcp.c tcp: restore autocorking 2018-05-03 11:28:50 -04:00
tcp_bbr.c tcp_bbr: fix to zero idle_restart only upon S/ACKed data 2018-05-02 11:12:32 -04:00
tcp_bic.c tcp: consolidate congestion control undo functions 2017-08-06 21:25:10 -07:00
tcp_cdg.c tcp: cdg: make struct tcp_cdg static 2017-10-16 21:24:25 +01:00
tcp_cong.c tcp: Namespace-ify sysctl_tcp_default_congestion_control 2017-11-15 14:09:52 +09:00
tcp_cubic.c tcp: consolidate congestion control undo functions 2017-08-06 21:25:10 -07:00
tcp_dctcp.c Revert "dctcp: update cwnd on congestion event" 2016-12-06 11:34:24 -05:00
tcp_diag.c net: sock: replace sk_state_load with inet_sk_state_load and remove sk_state_store 2017-12-20 14:00:25 -05:00
tcp_fastopen.c tcp: pause Fast Open globally after third consecutive timeout 2017-12-13 15:51:12 -05:00
tcp_highspeed.c tcp: consolidate congestion control undo functions 2017-08-06 21:25:10 -07:00
tcp_htcp.c tcp: fix cwnd undo in Reno and HTCP congestion controls 2017-08-06 21:25:10 -07:00
tcp_hybla.c tcp: make undo_cwnd mandatory for congestion modules 2016-11-21 13:20:17 -05:00
tcp_illinois.c net/tcp/illinois: replace broken algorithm reference link 2018-02-28 12:03:47 -05:00
tcp_input.c tcp: don't read out-of-bounds opsize 2018-04-23 09:51:06 -04:00
tcp_ipv4.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2018-03-31 23:33:04 -04:00
tcp_lp.c tcp: switch TCP TS option (RFC 7323) to 1ms clock 2017-05-17 16:06:01 -04:00
tcp_metrics.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
tcp_minisocks.c crypto : chtls - CPL handler definition 2018-03-31 23:37:32 -04:00
tcp_nv.c tcp_nv: fix potential integer overflow in tcpnv_acked 2018-01-31 10:26:30 -05:00
tcp_offload.c gso: validate gso_type in GSO handlers 2018-01-22 16:01:30 -05:00
tcp_output.c tcp: purge write queue in tcp_connect_init() 2018-05-16 12:18:00 -04:00
tcp_rate.c tcp: invalidate rate samples during SACK reneging 2017-12-08 10:07:02 -05:00
tcp_recovery.c tcp: evaluate packet losses upon RTT change 2017-12-08 14:14:11 -05:00
tcp_scalable.c tcp: consolidate congestion control undo functions 2017-08-06 21:25:10 -07:00
tcp_timer.c tcp: purge write queue upon aborting the connection 2018-03-07 15:01:03 -05:00
tcp_ulp.c net: add a UID to use for ULP socket assignment 2018-02-06 11:39:31 +01:00
tcp_vegas.c tcp: fix under-evaluated ssthresh in TCP Vegas 2017-09-29 06:07:00 +01:00
tcp_vegas.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
tcp_veno.c tcp: consolidate congestion control undo functions 2017-08-06 21:25:10 -07:00
tcp_westwood.c tcp: Revert "tcp: remove CA_ACK_SLOWPATH" 2017-08-30 11:20:08 -07:00
tcp_yeah.c tcp: consolidate congestion control undo functions 2017-08-06 21:25:10 -07:00
tunnel4.c inet: whitespace cleanup 2018-02-28 11:43:28 -05:00
udp.c ipv4: fix memory leaks in udp_sendmsg, ping_v4_sendmsg 2018-05-11 12:00:58 -04:00
udp_diag.c net: ipv6: add second dif to udp socket lookups 2017-08-07 11:39:22 -07:00
udp_impl.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
udp_offload.c gso: validate gso_type in GSO handlers 2018-01-22 16:01:30 -05:00
udp_tunnel.c net: add infrastructure to un-offload UDP tunnel port 2017-07-24 13:52:59 -07:00
udplite.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
xfrm4_input.c xfrm: Reinject transport-mode packets through tasklet 2017-12-19 08:23:21 +01:00
xfrm4_mode_beet.c networking: make skb_pull & friends return void pointers 2017-06-16 11:48:39 -04:00
xfrm4_mode_transport.c xfrm: Add encapsulation header offsets while SKB is not encrypted 2017-04-14 10:07:39 +02:00
xfrm4_mode_tunnel.c xfrm: Verify MAC header exists before overwriting eth_hdr(skb)->h_proto 2018-03-07 10:54:29 +01:00
xfrm4_output.c net: xfrm: use skb_gso_validate_network_len() to check gso sizes 2018-03-04 17:49:17 -05:00
xfrm4_policy.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
xfrm4_protocol.c xfrm: input: constify xfrm_input_afinfo 2017-02-09 10:22:17 +01:00
xfrm4_state.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
xfrm4_tunnel.c