linux/net/core
Eric Dumazet c305c6ae79 net: add annotations on hh->hh_len lockless accesses
KCSAN reported a data-race [1]

While we can use READ_ONCE() on the read sides,
we need to make sure hh->hh_len is written last.

[1]

BUG: KCSAN: data-race in eth_header_cache / neigh_resolve_output

write to 0xffff8880b9dedcb8 of 4 bytes by task 29760 on cpu 0:
 eth_header_cache+0xa9/0xd0 net/ethernet/eth.c:247
 neigh_hh_init net/core/neighbour.c:1463 [inline]
 neigh_resolve_output net/core/neighbour.c:1480 [inline]
 neigh_resolve_output+0x415/0x470 net/core/neighbour.c:1470
 neigh_output include/net/neighbour.h:511 [inline]
 ip6_finish_output2+0x7a2/0xec0 net/ipv6/ip6_output.c:116
 __ip6_finish_output net/ipv6/ip6_output.c:142 [inline]
 __ip6_finish_output+0x2d7/0x330 net/ipv6/ip6_output.c:127
 ip6_finish_output+0x41/0x160 net/ipv6/ip6_output.c:152
 NF_HOOK_COND include/linux/netfilter.h:294 [inline]
 ip6_output+0xf2/0x280 net/ipv6/ip6_output.c:175
 dst_output include/net/dst.h:436 [inline]
 NF_HOOK include/linux/netfilter.h:305 [inline]
 ndisc_send_skb+0x459/0x5f0 net/ipv6/ndisc.c:505
 ndisc_send_ns+0x207/0x430 net/ipv6/ndisc.c:647
 rt6_probe_deferred+0x98/0xf0 net/ipv6/route.c:615
 process_one_work+0x3d4/0x890 kernel/workqueue.c:2269
 worker_thread+0xa0/0x800 kernel/workqueue.c:2415
 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

read to 0xffff8880b9dedcb8 of 4 bytes by task 29572 on cpu 1:
 neigh_resolve_output net/core/neighbour.c:1479 [inline]
 neigh_resolve_output+0x113/0x470 net/core/neighbour.c:1470
 neigh_output include/net/neighbour.h:511 [inline]
 ip6_finish_output2+0x7a2/0xec0 net/ipv6/ip6_output.c:116
 __ip6_finish_output net/ipv6/ip6_output.c:142 [inline]
 __ip6_finish_output+0x2d7/0x330 net/ipv6/ip6_output.c:127
 ip6_finish_output+0x41/0x160 net/ipv6/ip6_output.c:152
 NF_HOOK_COND include/linux/netfilter.h:294 [inline]
 ip6_output+0xf2/0x280 net/ipv6/ip6_output.c:175
 dst_output include/net/dst.h:436 [inline]
 NF_HOOK include/linux/netfilter.h:305 [inline]
 ndisc_send_skb+0x459/0x5f0 net/ipv6/ndisc.c:505
 ndisc_send_ns+0x207/0x430 net/ipv6/ndisc.c:647
 rt6_probe_deferred+0x98/0xf0 net/ipv6/route.c:615
 process_one_work+0x3d4/0x890 kernel/workqueue.c:2269
 worker_thread+0xa0/0x800 kernel/workqueue.c:2415
 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 29572 Comm: kworker/1:4 Not tainted 5.4.0-rc6+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events rt6_probe_deferred

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-07 20:07:30 -08:00
..
Makefile
bpf_sk_storage.c
datagram.c net: add READ_ONCE() annotation in __skb_wait_for_more_packets() 2019-10-28 13:33:41 -07:00
datagram.h
dev.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-11-02 13:54:56 -07:00
dev_addr_lists.c net: remove unnecessary variables and callback 2019-10-24 14:53:49 -07:00
dev_ioctl.c
devlink.c devlink: Add layer 3 generic packet exception traps 2019-11-07 19:51:40 -08:00
drop_monitor.c
dst.c net: print proper warning on dst underflow 2019-09-26 09:05:56 +02:00
dst_cache.c
ethtool.c net: Zeroing the structure ethtool_wolinfo in ethtool_get_wol() 2019-10-26 11:20:10 -07:00
failover.c
fib_notifier.c net: fib_notifier: propagate extack down to the notifier block callback 2019-10-04 11:10:56 -07:00
fib_rules.c net: fib_notifier: propagate extack down to the notifier block callback 2019-10-04 11:10:56 -07:00
filter.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2019-10-26 22:57:27 -07:00
flow_dissector.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-11-02 13:54:56 -07:00
flow_offload.c
gen_estimator.c net_sched: gen_estimator: extend packet counter to 64bit 2019-11-06 21:51:36 -08:00
gen_stats.c net_sched: add TCA_STATS_PKT64 attribute 2019-11-05 18:20:55 -08:00
gro_cells.c
hwbm.c
link_watch.c
lwt_bpf.c bpf: lwtunnel: Fix reroute supplying invalid dst 2019-10-14 11:43:48 -07:00
lwtunnel.c
neighbour.c net: add annotations on hh->hh_len lockless accesses 2019-11-07 20:07:30 -08:00
net-procfs.c net: procfs: use index hashlist instead of name hashlist 2019-10-01 14:47:19 -07:00
net-sysfs.c
net-sysfs.h
net-traces.c
net_namespace.c netns: fix GFP flags in rtnl_net_notifyid() 2019-10-25 20:14:42 -07:00
netclassid_cgroup.c
netevent.c
netpoll.c
netprio_cgroup.c
page_pool.c
pktgen.c pktgen: remove unnecessary assignment in pktgen_xmit() 2019-10-17 14:25:13 -04:00
ptp_classifier.c
request_sock.c tcp: add rcu protection around tp->fastopen_rsk 2019-10-13 10:13:08 -07:00
rtnetlink.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-11-02 13:54:56 -07:00
scm.c
secure_seq.c
skbuff.c net/sched: fix corrupted L2 header with MPLS 'push' and 'pop' actions 2019-10-15 17:14:48 -07:00
skmsg.c
sock.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-11-02 13:54:56 -07:00
sock_diag.c
sock_map.c
sock_reuseport.c
stream.c
sysctl_net_core.c
timestamping.c
tso.c
utils.c
xdp.c xdp: Trivial, fix spelling in function description 2019-10-11 22:32:08 +02:00