linux/net/tipc
Eric Dumazet 70c2655849 net: silence KCSAN warnings about sk->sk_backlog.len reads
sk->sk_backlog.len can be written by BH handlers, and read
from process contexts in a lockless way.

Note the write side should also use WRITE_ONCE() or a variant.
We need some agreement about the best way to do this.

syzbot reported :

BUG: KCSAN: data-race in tcp_add_backlog / tcp_grow_window.isra.0

write to 0xffff88812665f32c of 4 bytes by interrupt on cpu 1:
 sk_add_backlog include/net/sock.h:934 [inline]
 tcp_add_backlog+0x4a0/0xcc0 net/ipv4/tcp_ipv4.c:1737
 tcp_v4_rcv+0x1aba/0x1bf0 net/ipv4/tcp_ipv4.c:1925
 ip_protocol_deliver_rcu+0x51/0x470 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:5004
 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5118
 netif_receive_skb_internal+0x59/0x190 net/core/dev.c:5208
 napi_skb_finish net/core/dev.c:5671 [inline]
 napi_gro_receive+0x28f/0x330 net/core/dev.c:5704
 receive_buf+0x284/0x30b0 drivers/net/virtio_net.c:1061
 virtnet_receive drivers/net/virtio_net.c:1323 [inline]
 virtnet_poll+0x436/0x7d0 drivers/net/virtio_net.c:1428
 napi_poll net/core/dev.c:6352 [inline]
 net_rx_action+0x3ae/0xa50 net/core/dev.c:6418

read to 0xffff88812665f32c of 4 bytes by task 7292 on cpu 0:
 tcp_space include/net/tcp.h:1373 [inline]
 tcp_grow_window.isra.0+0x6b/0x480 net/ipv4/tcp_input.c:413
 tcp_event_data_recv+0x68f/0x990 net/ipv4/tcp_input.c:717
 tcp_rcv_established+0xbfe/0xf50 net/ipv4/tcp_input.c:5618
 tcp_v4_do_rcv+0x381/0x4e0 net/ipv4/tcp_ipv4.c:1542
 sk_backlog_rcv include/net/sock.h:945 [inline]
 __release_sock+0x135/0x1e0 net/core/sock.c:2427
 release_sock+0x61/0x160 net/core/sock.c:2943
 tcp_recvmsg+0x63b/0x1a30 net/ipv4/tcp.c:2181
 inet_recvmsg+0xbb/0x250 net/ipv4/af_inet.c:838
 sock_recvmsg_nosec net/socket.c:871 [inline]
 sock_recvmsg net/socket.c:889 [inline]
 sock_recvmsg+0x92/0xb0 net/socket.c:885
 sock_read_iter+0x15f/0x1e0 net/socket.c:967
 call_read_iter include/linux/fs.h:1864 [inline]
 new_sync_read+0x389/0x4f0 fs/read_write.c:414
 __vfs_read+0xb1/0xc0 fs/read_write.c:427
 vfs_read fs/read_write.c:461 [inline]
 vfs_read+0x143/0x2c0 fs/read_write.c:446

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7292 Comm: syz-fuzzer Not tainted 5.3.0+ #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: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-09 21:43:00 -07:00
..
addr.c tipc: initialise addr_trail_end when setting node addresses 2019-08-11 21:40:04 -07:00
addr.h tipc: add 128-bit node identifier 2018-03-23 13:12:18 -04:00
bcast.c tipc: clean up skb list lock handling on send path 2019-08-18 14:01:07 -07:00
bcast.h tipc: fix a null pointer deref 2019-03-21 09:56:55 -07:00
bearer.c tipc: add loopback device tracking 2019-08-08 22:11:39 -07:00
bearer.h tipc: add loopback device tracking 2019-08-08 22:11:39 -07:00
core.c tipc: add loopback device tracking 2019-08-08 22:11:39 -07:00
core.h tipc: add loopback device tracking 2019-08-08 22:11:39 -07:00
diag.c tipc: switch to rhashtable iterator 2018-08-29 18:04:54 -07:00
discover.c tipc: fix lockdep warning when reinitilaizing sockets 2018-11-17 22:01:31 -08:00
discover.h tipc: some cleanups in the file discover.c 2018-03-23 13:12:17 -04:00
eth_media.c
group.c tipc: clean up skb list lock handling on send path 2019-08-18 14:01:07 -07:00
group.h tipc: extend sock diag for group communication 2018-06-30 21:05:42 +09:00
ib_media.c
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
link.c tipc: fix unlimited bundling of small messages 2019-10-02 11:02:05 -04:00
link.h tipc: fix missing Name entries due to half-failover 2019-05-04 00:59:51 -04:00
Makefile tipc: enable tracepoints in tipc 2018-12-19 11:49:24 -08:00
monitor.c netlink: make nla_nest_start() add NLA_F_NESTED flag 2019-04-27 17:03:44 -04:00
monitor.h
msg.c tipc: fix unlimited bundling of small messages 2019-10-02 11:02:05 -04:00
msg.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-08-19 11:54:03 -07:00
name_distr.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-09-15 14:17:27 +02:00
name_distr.h tipc: permit overlapping service ranges in name table 2018-03-31 22:19:52 -04:00
name_table.c netlink: make nla_nest_start() add NLA_F_NESTED flag 2019-04-27 17:03:44 -04:00
name_table.h tipc: eliminate message disordering during binding table update 2018-10-22 19:29:12 -07:00
net.c netlink: make validation more configurable for future strictness 2019-04-27 17:07:21 -04:00
net.h tipc: fix lockdep warning when reinitilaizing sockets 2018-11-17 22:01:31 -08:00
netlink_compat.c tipc: compat: allow tipc commands without arguments 2019-08-01 18:14:00 -04:00
netlink.c tipc: fix missing indentation in source code 2019-06-24 07:29:45 -07:00
netlink.h
node.c tipc: clean up skb list lock handling on send path 2019-08-18 14:01:07 -07:00
node.h tipc: optimize link synching mechanism 2019-07-25 15:55:47 -07:00
socket.c net: silence KCSAN warnings about sk->sk_backlog.len reads 2019-10-09 21:43:00 -07:00
socket.h tipc: add trace_events for tipc socket 2018-12-19 11:49:24 -08:00
subscr.c tipc: fix unbalanced reference counter 2018-04-12 21:46:10 -04:00
subscr.h tipc: fix modprobe tipc failed after switch order of device registration 2019-05-20 10:45:43 -07:00
sysctl.c proc/sysctl: add shared variables for range check 2019-07-18 17:08:07 -07:00
topsrv.c tipc: add loopback device tracking 2019-08-08 22:11:39 -07:00
topsrv.h tipc: rename tipc_server to tipc_topsrv 2018-02-16 15:26:34 -05:00
trace.c tipc: remove unneeded semicolon in trace.c 2019-01-17 22:04:43 -08:00
trace.h tipc: add trace_events for tipc bearer 2018-12-19 11:49:25 -08:00
udp_media.c tipc: use rcu dereference functions properly 2019-07-07 13:18:53 -07:00
udp_media.h tipc: implement configuration of UDP media MTU 2018-04-20 11:04:05 -04:00