KCSAN: data-race in geneve_xmit / geneve

KCSAN: data-race in geneve_xmit / geneve_xmit
Status: auto-closed as invalid on 2020/05/17 12:40
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 600d, last: 563d

similar bugs (1):
Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in geneve_xmit / geneve_xmit (2)				1	288d	288d	0/22	auto-closed as invalid on 2021/01/12 17:00

Sample crash report:

==================================================================
BUG: KCSAN: data-race in geneve_xmit / geneve_xmit

write to 0xffff8880a349e130 of 8 bytes by task 7138 on cpu 1:
 geneve_xmit+0x70e/0x13b9 drivers/net/geneve.c:1017
 __netdev_start_xmit include/linux/netdevice.h:4510 [inline]
 netdev_start_xmit include/linux/netdevice.h:4524 [inline]
 xmit_one net/core/dev.c:3470 [inline]
 dev_hard_start_xmit+0xeb/0x420 net/core/dev.c:3486
 __dev_queue_xmit+0x14c4/0x1b80 net/core/dev.c:4063
 dev_queue_xmit+0x1e/0x30 net/core/dev.c:4096
 neigh_hh_output include/net/neighbour.h:499 [inline]
 neigh_output include/net/neighbour.h:508 [inline]
 ip_finish_output2+0x87d/0xed0 net/ipv4/ip_output.c:228
 __ip_finish_output net/ipv4/ip_output.c:306 [inline]
 __ip_finish_output+0x22f/0x460 net/ipv4/ip_output.c:288
 ip_finish_output+0x3e/0x160 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_mc_output+0x13e/0x620 net/ipv4/ip_output.c:415
 dst_output include/net/dst.h:436 [inline]
 ip_local_out+0x70/0x90 net/ipv4/ip_output.c:125
 ip_send_skb+0x32/0xb0 net/ipv4/ip_output.c:1560
 udp_send_skb.isra.0+0x3b8/0x8d0 net/ipv4/udp.c:891
 udp_sendmsg+0x1589/0x1930 net/ipv4/udp.c:1178
 inet_sendmsg+0x69/0x90 net/ipv4/af_inet.c:807
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0x98/0xc0 net/socket.c:672
 ____sys_sendmsg+0x207/0x4c0 net/socket.c:2343
 ___sys_sendmsg+0xb5/0x100 net/socket.c:2397
 __sys_sendmmsg+0x10e/0x310 net/socket.c:2487
 __do_sys_sendmmsg net/socket.c:2516 [inline]
 __se_sys_sendmmsg net/socket.c:2513 [inline]
 __x64_sys_sendmmsg+0x60/0x80 net/socket.c:2513
 do_syscall_64+0xc7/0x390 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff8880a349e130 of 8 bytes by task 7053 on cpu 0:
 geneve_xmit+0x6fb/0x13b9 drivers/net/geneve.c:1017
 __netdev_start_xmit include/linux/netdevice.h:4510 [inline]
 netdev_start_xmit include/linux/netdevice.h:4524 [inline]
 xmit_one net/core/dev.c:3470 [inline]
 dev_hard_start_xmit+0xeb/0x420 net/core/dev.c:3486
 __dev_queue_xmit+0x14c4/0x1b80 net/core/dev.c:4063
 dev_queue_xmit+0x1e/0x30 net/core/dev.c:4096
 neigh_hh_output include/net/neighbour.h:499 [inline]
 neigh_output include/net/neighbour.h:508 [inline]
 ip_finish_output2+0x87d/0xed0 net/ipv4/ip_output.c:228
 __ip_finish_output net/ipv4/ip_output.c:306 [inline]
 __ip_finish_output+0x22f/0x460 net/ipv4/ip_output.c:288
 ip_finish_output+0x3e/0x160 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_mc_output+0x13e/0x620 net/ipv4/ip_output.c:415
 dst_output include/net/dst.h:436 [inline]
 ip_local_out+0x70/0x90 net/ipv4/ip_output.c:125
 ip_send_skb+0x32/0xb0 net/ipv4/ip_output.c:1560
 udp_send_skb.isra.0+0x3b8/0x8d0 net/ipv4/udp.c:891
 udp_sendmsg+0x1589/0x1930 net/ipv4/udp.c:1178
 inet_sendmsg+0x69/0x90 net/ipv4/af_inet.c:807
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0x98/0xc0 net/socket.c:672
 ____sys_sendmsg+0x207/0x4c0 net/socket.c:2343
 ___sys_sendmsg+0xb5/0x100 net/socket.c:2397
 __sys_sendmmsg+0x10e/0x310 net/socket.c:2487
 __do_sys_sendmmsg net/socket.c:2516 [inline]
 __se_sys_sendmmsg net/socket.c:2513 [inline]
 __x64_sys_sendmmsg+0x60/0x80 net/socket.c:2513
 do_syscall_64+0xc7/0x390 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7053 Comm: syz-executor.0 Not tainted 5.6.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (4):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report
ci2-upstream-kcsan-gce	2020/03/08 12:39	https://github.com/google/ktsan.git kcsan	941e0d917bbf	2e9971bb	.config	log	report
ci2-upstream-kcsan-gce	2020/02/25 18:36	https://github.com/google/ktsan.git kcsan	766d004d1b85	4c886d6a	.config	log	report
ci2-upstream-kcsan-gce	2020/02/16 19:13	https://github.com/google/ktsan.git kcsan	b12d66a6c34f	cf914200	.config	log	report
ci2-upstream-kcsan-gce	2020/01/30 19:19	https://github.com/google/ktsan.git kcsan	245a43005292	5ed23f9a	.config	log	report