linux-uconsole/net
Eric Dumazet ab6c0f501d packet: fix data-race in fanout_flow_is_huge()
[ Upstream commit b756ad928d ]

KCSAN reported the following data-race [1]

Adding a couple of READ_ONCE()/WRITE_ONCE() should silence it.

Since the report hinted about multiple cpus using the history
concurrently, I added a test avoiding writing on it if the
victim slot already contains the desired value.

[1]

BUG: KCSAN: data-race in fanout_demux_rollover / fanout_demux_rollover

read to 0xffff8880b01786cc of 4 bytes by task 18921 on cpu 1:
 fanout_flow_is_huge net/packet/af_packet.c:1303 [inline]
 fanout_demux_rollover+0x33e/0x3f0 net/packet/af_packet.c:1353
 packet_rcv_fanout+0x34e/0x490 net/packet/af_packet.c:1453
 deliver_skb net/core/dev.c:1888 [inline]
 dev_queue_xmit_nit+0x15b/0x540 net/core/dev.c:1958
 xmit_one net/core/dev.c:3195 [inline]
 dev_hard_start_xmit+0x3f5/0x430 net/core/dev.c:3215
 __dev_queue_xmit+0x14ab/0x1b40 net/core/dev.c:3792
 dev_queue_xmit+0x21/0x30 net/core/dev.c:3825
 neigh_direct_output+0x1f/0x30 net/core/neighbour.c:1530
 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]
 ip6_local_out+0x74/0x90 net/ipv6/output_core.c:179
 ip6_send_skb+0x53/0x110 net/ipv6/ip6_output.c:1795
 udp_v6_send_skb.isra.0+0x3ec/0xa70 net/ipv6/udp.c:1173
 udpv6_sendmsg+0x1906/0x1c20 net/ipv6/udp.c:1471
 inet6_sendmsg+0x6d/0x90 net/ipv6/af_inet6.c:576
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg+0x9f/0xc0 net/socket.c:657
 ___sys_sendmsg+0x2b7/0x5d0 net/socket.c:2311
 __sys_sendmmsg+0x123/0x350 net/socket.c:2413
 __do_sys_sendmmsg net/socket.c:2442 [inline]
 __se_sys_sendmmsg net/socket.c:2439 [inline]
 __x64_sys_sendmmsg+0x64/0x80 net/socket.c:2439
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff8880b01786cc of 4 bytes by task 18922 on cpu 0:
 fanout_flow_is_huge net/packet/af_packet.c:1306 [inline]
 fanout_demux_rollover+0x3a4/0x3f0 net/packet/af_packet.c:1353
 packet_rcv_fanout+0x34e/0x490 net/packet/af_packet.c:1453
 deliver_skb net/core/dev.c:1888 [inline]
 dev_queue_xmit_nit+0x15b/0x540 net/core/dev.c:1958
 xmit_one net/core/dev.c:3195 [inline]
 dev_hard_start_xmit+0x3f5/0x430 net/core/dev.c:3215
 __dev_queue_xmit+0x14ab/0x1b40 net/core/dev.c:3792
 dev_queue_xmit+0x21/0x30 net/core/dev.c:3825
 neigh_direct_output+0x1f/0x30 net/core/neighbour.c:1530
 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]
 ip6_local_out+0x74/0x90 net/ipv6/output_core.c:179
 ip6_send_skb+0x53/0x110 net/ipv6/ip6_output.c:1795
 udp_v6_send_skb.isra.0+0x3ec/0xa70 net/ipv6/udp.c:1173
 udpv6_sendmsg+0x1906/0x1c20 net/ipv6/udp.c:1471
 inet6_sendmsg+0x6d/0x90 net/ipv6/af_inet6.c:576
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg+0x9f/0xc0 net/socket.c:657
 ___sys_sendmsg+0x2b7/0x5d0 net/socket.c:2311
 __sys_sendmmsg+0x123/0x350 net/socket.c:2413
 __do_sys_sendmmsg net/socket.c:2442 [inline]
 __se_sys_sendmmsg net/socket.c:2439 [inline]
 __x64_sys_sendmmsg+0x64/0x80 net/socket.c:2439
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 18922 Comm: syz-executor.3 Not tainted 5.4.0-rc6+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Fixes: 3b3a5b0aab ("packet: rollover huge flows before small flows")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-27 14:51:21 +01:00
..
6lowpan 6lowpan: Off by one handling ->nexthdr 2020-01-27 14:50:41 +01:00
9p 9p: Transport error uninitialized 2019-10-11 18:21:12 +02:00
802
8021q vlan: vlan_changelink() should propagate errors 2020-01-12 12:17:28 +01:00
appletalk appletalk: Set error code if register_snap_client failed 2019-12-13 08:52:59 +01:00
atm net: use skb_queue_empty_lockless() in poll() handlers 2019-11-10 11:27:48 +01:00
ax25 ax25: enforce CAP_NET_RAW for raw sockets 2019-10-05 13:09:32 +02:00
batman-adv batman-adv: Fix DAT candidate selection on little endian systems 2020-01-23 08:21:34 +01:00
bluetooth Bluetooth: Fix memory leak in hci_connect_le_scan 2020-01-09 10:19:04 +01:00
bpf bpf/test_run: support cgroup local storage 2018-08-03 00:47:32 +02:00
bpfilter signal/bpfilter: Fix bpfilter_kernl to use send_sig not force_sig 2020-01-27 14:50:51 +01:00
bridge netfilter: ebtables: CONFIG_COMPAT: reject trailing data after last rule 2020-01-27 14:50:47 +01:00
caif net: use skb_queue_empty_lockless() in poll() handlers 2019-11-10 11:27:48 +01:00
can can: gw: Fix error path of cgw_module_init 2019-08-29 08:28:30 +02:00
ceph libceph: fix PG split vs OSD (re)connect race 2019-08-29 08:28:50 +02:00
core net: neigh: use long type to store jiffies delta 2020-01-27 14:51:21 +01:00
dcb net: dcb: Add priority-to-DSCP map getters 2018-07-27 13:17:50 -07:00
dccp dccp: Fix memleak in __feat_register_sp 2020-01-17 19:46:58 +01:00
decnet net: add bool confirm_neigh parameter for dst_ops.update_pmtu 2020-01-04 19:13:37 +01:00
dns_resolver net: remove blank lines at end of file 2018-07-24 14:10:43 -07:00
dsa net: dsa: Avoid null pointer when failing to connect to PHY 2020-01-27 14:50:34 +01:00
ethernet net: add annotations on hh->hh_len lockless accesses 2020-01-09 10:19:09 +01:00
hsr hsr: reset network header when supervision frame is created 2020-01-17 19:47:00 +01:00
ieee802154 inet: frags: call inet_frags_fini() after unregister_pernet_subsys() 2020-01-27 14:50:51 +01:00
ife
ipv4 tcp: annotate lockless access to tcp_memory_pressure 2020-01-27 14:51:18 +01:00
ipv6 ip6erspan: remove the incorrect mtu limit for ip6erspan 2020-01-27 14:51:17 +01:00
iucv net/af_iucv: always register net_device notifier 2020-01-27 14:50:56 +01:00
kcm kcm: switch order of device registration to fix a crash 2019-04-17 08:38:40 +02:00
key af_key: fix leaks in key_pol_get_resp and dump_sp. 2019-07-26 09:14:01 +02:00
l2tp l2tp: Fix possible NULL pointer dereference 2020-01-27 14:50:46 +01:00
l3mdev
lapb lapb: fixed leak of control-blocks. 2019-06-22 08:15:13 +02:00
llc llc: fix sk_buff refcounting in llc_conn_state_process() 2020-01-27 14:51:17 +01:00
mac80211 mac80211: accept deauth frames in IBSS mode 2020-01-27 14:51:16 +01:00
mac802154 net: mac802154: tx: expand tailroom if necessary 2018-08-06 11:21:37 +02:00
mpls mpls: fix warning with multi-label encap 2020-01-27 14:50:54 +01:00
ncsi net/ncsi: Fixup .dumpit message flags and ID check in Netlink handler 2018-08-22 21:39:08 -07:00
netfilter netfilter: ctnetlink: honor IPS_OFFLOAD flag 2020-01-27 14:51:09 +01:00
netlabel netlabel: fix out-of-bounds memory accesses 2019-03-10 07:17:18 +01:00
netlink genetlink: Fix a memory leak on error path 2019-04-03 06:26:15 +02:00
netrom netrom: hold sock when setting skb->destructor 2019-07-28 08:29:27 +02:00
nfc net: nfc: nci: fix a possible sleep-in-atomic-context bug in nci_uart_tty_receive() 2019-12-31 16:34:38 +01:00
nsh
openvswitch openvswitch: support asymmetric conntrack 2019-12-21 10:57:14 +01:00
packet packet: fix data-race in fanout_flow_is_huge() 2020-01-27 14:51:21 +01:00
phonet net: use skb_queue_empty_lockless() in poll() handlers 2019-11-10 11:27:48 +01:00
psample net: psample: fix skb_over_panic 2019-12-05 09:21:30 +01:00
qrtr net: qrtr: fix memort leak in qrtr_tun_write_iter 2019-12-13 08:52:58 +01:00
rds net/rds: Fix 'ib_evt_handler_call' element in 'rds_ib_stat_names' 2020-01-27 14:51:13 +01:00
rfkill rfkill: Fix incorrect check to avoid NULL pointer dereference 2020-01-12 12:17:17 +01:00
rose net/rose: fix unbound loop in rose_loopback_timer() 2019-05-02 09:59:00 +02:00
rxrpc rxrpc: Fix trace-after-put looking at the put connection record 2020-01-27 14:51:16 +01:00
sched net: netem: correct the parent's backlog when corrupted packet was dropped 2020-01-27 14:51:19 +01:00
sctp sctp: add chunks to sk_backlog when the newsk sk_socket is not set 2020-01-27 14:51:17 +01:00
smc net/smc: receive pending data after RCV_SHUTDOWN 2020-01-27 14:51:18 +01:00
strparser net: strparser: partially revert "strparser: Call skb_unclone conditionally" 2019-05-16 19:41:27 +02:00
sunrpc xprtrdma: Fix use-after-free in rpcrdma_post_recvs 2020-01-27 14:50:59 +01:00
switchdev
tipc tipc: reduce risk of wakeup queue starvation 2020-01-27 14:51:02 +01:00
tls net/tls: fix socket wmem accounting on fallback with netem 2020-01-27 14:51:01 +01:00
unix af_unix: add compat_ioctl support 2020-01-17 19:47:07 +01:00
vmw_vsock VSOCK: bind to random port for VMADDR_PORT_ANY 2019-12-05 09:20:19 +01:00
wimax wimax: remove blank lines at EOF 2018-07-24 14:10:42 -07:00
wireless cfg80211: regulatory: make initialization more robust 2020-01-27 14:49:57 +01:00
x25 net/x25: fix null_x25_address handling 2019-12-13 08:52:15 +01:00
xdp xsk: Fix registration of Rx-only sockets 2020-01-27 14:51:19 +01:00
xfrm xfrm interface: ifname may be wrong in logs 2020-01-27 14:51:01 +01:00
compat.c sock: Make sock->sk_stamp thread-safe 2019-01-09 17:38:33 +01:00
Kconfig net: remove blank lines at end of file 2018-07-24 14:10:43 -07:00
Makefile
socket.c compat_ioctl: handle SIOCOUTQNSD 2020-01-17 19:47:07 +01:00
sysctl_net.c