KCSAN: data-race in dev_get_tstats64 / wg_packet_rx

KCSAN: data-race in dev_get_tstats64 / wg_packet_rx_poll
Status: auto-closed as invalid on 2021/04/16 07:34
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 139d, last: 139d

Sample crash report:

==================================================================
BUG: KCSAN: data-race in dev_get_tstats64 / wg_packet_rx_poll

write to 0xffffe8ffffc60208 of 8 bytes by interrupt on cpu 0:
 update_rx_stats drivers/net/wireguard/receive.c:27 [inline]
 wg_packet_consume_data_done drivers/net/wireguard/receive.c:364 [inline]
 wg_packet_rx_poll+0xec8/0x11b0 drivers/net/wireguard/receive.c:480
 __napi_poll+0x77/0x510 net/core/dev.c:6892
 napi_poll net/core/dev.c:6959 [inline]
 net_rx_action+0x29f/0x680 net/core/dev.c:7036
 __do_softirq+0x13c/0x2c3 kernel/softirq.c:345
 do_softirq+0x73/0xa0 kernel/softirq.c:248
 __local_bh_enable_ip+0x5a/0x60 kernel/softirq.c:198
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:176 [inline]
 _raw_spin_unlock_bh+0x33/0x40 kernel/locking/spinlock.c:207
 spin_unlock_bh include/linux/spinlock.h:399 [inline]
 ptr_ring_consume_bh include/linux/ptr_ring.h:367 [inline]
 wg_packet_decrypt_worker+0x732/0x770 drivers/net/wireguard/receive.c:505
 process_one_work+0x3e1/0x950 kernel/workqueue.c:2275
 worker_thread+0x616/0xa70 kernel/workqueue.c:2421
 kthread+0x20b/0x230 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

read to 0xffffe8ffffc60208 of 8 bytes by task 8398 on cpu 1:
 dev_fetch_sw_netstats net/core/dev.c:10559 [inline]
 dev_get_tstats64+0xeb/0x1d0 net/core/dev.c:10583
 dev_get_stats+0x65/0x180 net/core/dev.c:10525
 rtnl_fill_stats+0x45/0x320 net/core/rtnetlink.c:1211
 rtnl_fill_ifinfo+0xe98/0x2440 net/core/rtnetlink.c:1783
 rtmsg_ifinfo_build_skb+0xa8/0x130 net/core/rtnetlink.c:3798
 rtmsg_ifinfo_event net/core/rtnetlink.c:3830 [inline]
 rtmsg_ifinfo+0x58/0xc0 net/core/rtnetlink.c:3839
 __dev_notify_flags+0x63/0x3a0 net/core/dev.c:8691
 dev_change_flags+0xa2/0xc0 net/core/dev.c:8733
 do_setlink+0x746/0x2280 net/core/rtnetlink.c:2708
 __rtnl_newlink net/core/rtnetlink.c:3376 [inline]
 rtnl_newlink+0xe7e/0x1310 net/core/rtnetlink.c:3491
 rtnetlink_rcv_msg+0x728/0x7c0 net/core/rtnetlink.c:5553
 netlink_rcv_skb+0x13e/0x240 net/netlink/af_netlink.c:2502
 rtnetlink_rcv+0x18/0x20 net/core/rtnetlink.c:5571
 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
 netlink_unicast+0x5fc/0x6c0 net/netlink/af_netlink.c:1338
 netlink_sendmsg+0x6f8/0x7c0 net/netlink/af_netlink.c:1927
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg net/socket.c:674 [inline]
 __sys_sendto+0x2a8/0x370 net/socket.c:1977
 __do_sys_sendto net/socket.c:1989 [inline]
 __se_sys_sendto net/socket.c:1985 [inline]
 __x64_sys_sendto+0x74/0x90 net/socket.c:1985
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 8398 Comm: syz-executor.1 Not tainted 5.12.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Title
ci2-upstream-kcsan-gce	2021/03/12 07:27	upstream	28806e4d9b97	429d8a6b	.config	log	report			info	KCSAN: data-race in dev_get_tstats64 / wg_packet_rx_poll