linux/net/ipv6
Eric Dumazet 5e5265522a tcp: annotate data-races around tcp_rsk(req)->txhash
TCP request sockets are lockless, some of their fields
can change while being read by another cpu as syzbot noticed.

This is usually harmless, but we should annotate the known
races.

This patch takes care of tcp_rsk(req)->txhash,
a separate one is needed for tcp_rsk(req)->ts_recent.

BUG: KCSAN: data-race in tcp_make_synack / tcp_rtx_synack

write to 0xffff8881362304bc of 4 bytes by task 32083 on cpu 1:
tcp_rtx_synack+0x9d/0x2a0 net/ipv4/tcp_output.c:4213
inet_rtx_syn_ack+0x38/0x80 net/ipv4/inet_connection_sock.c:880
tcp_check_req+0x379/0xc70 net/ipv4/tcp_minisocks.c:665
tcp_v6_rcv+0x125b/0x1b20 net/ipv6/tcp_ipv6.c:1673
ip6_protocol_deliver_rcu+0x92f/0xf30 net/ipv6/ip6_input.c:437
ip6_input_finish net/ipv6/ip6_input.c:482 [inline]
NF_HOOK include/linux/netfilter.h:303 [inline]
ip6_input+0xbd/0x1b0 net/ipv6/ip6_input.c:491
dst_input include/net/dst.h:468 [inline]
ip6_rcv_finish+0x1e2/0x2e0 net/ipv6/ip6_input.c:79
NF_HOOK include/linux/netfilter.h:303 [inline]
ipv6_rcv+0x74/0x150 net/ipv6/ip6_input.c:309
__netif_receive_skb_one_core net/core/dev.c:5452 [inline]
__netif_receive_skb+0x90/0x1b0 net/core/dev.c:5566
netif_receive_skb_internal net/core/dev.c:5652 [inline]
netif_receive_skb+0x4a/0x310 net/core/dev.c:5711
tun_rx_batched+0x3bf/0x400
tun_get_user+0x1d24/0x22b0 drivers/net/tun.c:1997
tun_chr_write_iter+0x18e/0x240 drivers/net/tun.c:2043
call_write_iter include/linux/fs.h:1871 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x4ab/0x7d0 fs/read_write.c:584
ksys_write+0xeb/0x1a0 fs/read_write.c:637
__do_sys_write fs/read_write.c:649 [inline]
__se_sys_write fs/read_write.c:646 [inline]
__x64_sys_write+0x42/0x50 fs/read_write.c:646
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff8881362304bc of 4 bytes by task 32078 on cpu 0:
tcp_make_synack+0x367/0xb40 net/ipv4/tcp_output.c:3663
tcp_v6_send_synack+0x72/0x420 net/ipv6/tcp_ipv6.c:544
tcp_conn_request+0x11a8/0x1560 net/ipv4/tcp_input.c:7059
tcp_v6_conn_request+0x13f/0x180 net/ipv6/tcp_ipv6.c:1175
tcp_rcv_state_process+0x156/0x1de0 net/ipv4/tcp_input.c:6494
tcp_v6_do_rcv+0x98a/0xb70 net/ipv6/tcp_ipv6.c:1509
tcp_v6_rcv+0x17b8/0x1b20 net/ipv6/tcp_ipv6.c:1735
ip6_protocol_deliver_rcu+0x92f/0xf30 net/ipv6/ip6_input.c:437
ip6_input_finish net/ipv6/ip6_input.c:482 [inline]
NF_HOOK include/linux/netfilter.h:303 [inline]
ip6_input+0xbd/0x1b0 net/ipv6/ip6_input.c:491
dst_input include/net/dst.h:468 [inline]
ip6_rcv_finish+0x1e2/0x2e0 net/ipv6/ip6_input.c:79
NF_HOOK include/linux/netfilter.h:303 [inline]
ipv6_rcv+0x74/0x150 net/ipv6/ip6_input.c:309
__netif_receive_skb_one_core net/core/dev.c:5452 [inline]
__netif_receive_skb+0x90/0x1b0 net/core/dev.c:5566
netif_receive_skb_internal net/core/dev.c:5652 [inline]
netif_receive_skb+0x4a/0x310 net/core/dev.c:5711
tun_rx_batched+0x3bf/0x400
tun_get_user+0x1d24/0x22b0 drivers/net/tun.c:1997
tun_chr_write_iter+0x18e/0x240 drivers/net/tun.c:2043
call_write_iter include/linux/fs.h:1871 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x4ab/0x7d0 fs/read_write.c:584
ksys_write+0xeb/0x1a0 fs/read_write.c:637
__do_sys_write fs/read_write.c:649 [inline]
__se_sys_write fs/read_write.c:646 [inline]
__x64_sys_write+0x42/0x50 fs/read_write.c:646
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x91d25731 -> 0xe79325cd

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 32078 Comm: syz-executor.4 Not tainted 6.5.0-rc1-syzkaller-00033-geb26cbb1a754 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023

Fixes: 58d607d3e5 ("tcp: provide skb->hash to synack packets")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20230717144445.653164-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-07-18 19:45:27 -07:00
..
ila ila: do not generate empty messages in ila_xlat_nl_cmd_get_mapping() 2023-03-01 08:48:46 +00:00
netfilter Revert "net: Remove low_thresh in ip defrag" 2023-05-16 20:46:30 -07:00
addrconf.c ipv6/addrconf: fix a potential refcount underflow for idev 2023-07-09 11:19:01 +01:00
addrconf_core.c net: rename reference+tracking helpers 2022-06-09 21:52:55 -07:00
addrlabel.c ipv6: addrlabel: fix infoleak when sending struct ifaddrlblmsg to network 2022-11-07 12:26:15 +00:00
af_inet6.c sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES) 2023-06-24 15:50:13 -07:00
ah6.c net: ipv6: Remove completion function scaffolding 2023-02-13 18:35:15 +08:00
anycast.c
calipso.c cipso,calipso: resolve a number of problems with the DOI refcounts 2021-03-04 15:26:57 -08:00
datagram.c ipv6: Fix datagram socket connection with DSCP. 2023-02-09 22:49:04 -08:00
esp6.c net: ipv6: Remove completion function scaffolding 2023-02-13 18:35:15 +08:00
esp6_offload.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2023-06-22 18:40:38 -07:00
exthdrs.c ipv6: exthdrs: Remove redundant skb_headlen() check in ip6_parse_tlv(). 2023-06-19 11:32:58 -07:00
exthdrs_core.c ipv6: Fix out-of-bounds access in ipv6_find_tlv() 2023-05-24 08:43:39 +01:00
exthdrs_offload.c
fib6_notifier.c
fib6_rules.c ipv6: change fib6_rules_net_exit() to batch mode 2022-02-08 20:41:34 -08:00
fou6.c
icmp.c icmp6: Fix null-ptr-deref of ip6_null_entry->rt6i_idev in icmp6_dev(). 2023-07-08 10:08:54 +01:00
inet6_connection_sock.c net: annotate lockless accesses to sk->sk_err_soft 2023-03-17 08:25:05 +00:00
inet6_hashtables.c tcp: Access &tcp_hashinfo via net. 2022-09-20 10:21:49 -07:00
ioam6.c genetlink: start to validate reserved header bytes 2022-08-29 12:47:15 +01:00
ioam6_iptunnel.c ipv6: ioam: Insertion frequency in lwtunnel output 2022-02-04 20:24:45 -08:00
ip6_checksum.c
ip6_fib.c ipv6: remove nexthop_fib6_nh_bh() 2023-05-11 18:07:05 -07:00
ip6_flowlabel.c ipv6: flowlabel: do not disable BH where not needed 2023-03-21 21:32:18 -07:00
ip6_gre.c erspan: get the proto with the md version for collect_md 2023-05-13 16:58:58 +01:00
ip6_icmp.c net: icmp: pass zeroed opts from icmp{,v6}_ndo_send before sending 2021-02-23 11:29:52 -08:00
ip6_input.c netfilter: keep conntrack reference until IPsecv6 policy checks are done 2023-03-22 21:50:23 +01:00
ip6_offload.c net: move gso declarations and functions to their own files 2023-06-10 00:11:41 -07:00
ip6_offload.h
ip6_output.c ip, ip6: Fix splice to raw and ping sockets 2023-06-16 11:45:16 -07:00
ip6_tunnel.c net: tunnels: annotate lockless accesses to dev->needed_headroom 2023-03-15 00:04:04 -07:00
ip6_udp_tunnel.c
ip6_vti.c ipv6: tunnels: use DEV_STATS_INC() 2022-11-16 12:48:44 +00:00
ip6mr.c net: ioctl: Use kernel memory on protocol ioctl callbacks 2023-06-15 22:33:26 -07:00
ipcomp6.c xfrm: ipcomp: add extack to ipcomp{4,6}_init_state 2022-09-29 07:18:00 +02:00
ipv6_sockglue.c net/ipv6: Initialise msg_control_is_user 2023-04-14 11:09:27 +01:00
Kconfig crypto: lib - make the sha1 library optional 2022-07-15 16:43:59 +08:00
Makefile net: ipv6: use ipv6-y directly instead of ipv6-objs 2021-09-28 13:13:40 +01:00
mcast.c ipv6: constify inet6_mc_check() 2023-03-17 08:56:37 +00:00
mcast_snoop.c net: bridge: mcast: fix broken length + header check for MRDv6 Adv. 2021-04-27 14:02:06 -07:00
mip6.c xfrm: mip6: add extack to mip6_destopt_init_state, mip6_rthdr_init_state 2022-09-29 07:18:01 +02:00
ndisc.c neighbour: annotate lockless accesses to n->nud_state 2023-03-15 00:37:32 -07:00
netfilter.c netfilter: Use l3mdev flow key when re-routing mangled packets 2022-05-16 13:03:29 +02:00
output_core.c treewide: use get_random_u32_{above,below}() instead of manual loop 2022-11-18 02:15:22 +01:00
ping.c ping6: Fix send to link-local addresses with VRF. 2023-06-08 18:59:57 -07:00
proc.c icmp: Add counters for rate limits 2023-01-26 10:52:18 +01:00
protocol.c
raw.c sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES) 2023-06-24 15:50:13 -07:00
reassembly.c Revert "net: Remove low_thresh in ip defrag" 2023-05-16 20:46:30 -07:00
route.c ipv6: also use netdev_hold() in ip6_route_check_nh() 2023-06-18 14:27:45 +01:00
rpl.c ipv6: rpl: Remove pskb(_may)?_pull() in ipv6_rpl_srh_rcv(). 2023-06-19 11:32:58 -07:00
rpl_iptunnel.c net: ipv6: rpl_iptunnel: Replace 0-length arrays with flexible arrays 2023-01-06 19:28:01 -08:00
seg6.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-09-08 18:38:30 +02:00
seg6_hmac.c net: ipv6: unexport __init-annotated seg6_hmac_net_init() 2022-06-28 21:23:30 -07:00
seg6_iptunnel.c seg6: Cleanup duplicates of skb_dst_drop calls 2023-05-17 09:05:47 +01:00
seg6_local.c seg6: add PSP flavor support for SRv6 End behavior 2023-02-16 13:18:06 +01:00
sit.c sit: update dev->needed_headroom in ipip6_tunnel_bind_dev() 2023-04-28 09:48:14 +01:00
syncookies.c tcp: Fix data-races around sysctl_tcp_syncookies. 2022-07-18 12:21:54 +01:00
sysctl_net_ipv6.c net: sysctl: introduce sysctl SYSCTL_THREE 2022-05-03 10:15:06 +02:00
tcp_ipv6.c tcp: annotate data-races around tcp_rsk(req)->txhash 2023-07-18 19:45:27 -07:00
tcpv6_offload.c net: Make gro complete function to return void 2023-05-31 09:50:17 +01:00
tunnel6.c
udp.c udp6: fix udp6_ehashfn() typo 2023-07-08 15:20:48 +01:00
udp_impl.h tcp/udp: Call inet6_destroy_sock() in IPv6 sk->sk_destruct(). 2022-10-12 17:50:37 -07:00
udp_offload.c gso: fix dodgy bit handling for GSO_UDP_L4 2023-07-14 10:29:20 +01:00
udplite.c udplite: Print deprecation notice. 2023-06-15 15:08:58 -07:00
xfrm6_input.c xfrm: fix inbound ipv4/udp/esp packets to UDPv6 dualstack sockets 2023-06-09 08:16:34 +02:00
xfrm6_output.c xfrm: fix tunnel model fragmentation behavior 2022-03-01 12:08:40 +01:00
xfrm6_policy.c net: dst: fix missing initialization of rt_uncached 2023-04-21 20:26:56 -07:00
xfrm6_protocol.c
xfrm6_state.c
xfrm6_tunnel.c xfrm: tunnel: add extack to ipip_init_state, xfrm6_tunnel_init_state 2022-09-29 07:18:00 +02:00