syzbot


KCSAN: data-race in dev_queue_xmit_nit / packet_setsockopt

Status: fixed on 2024/04/10 03:59
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+c669c1136495a2e7c31f@syzkaller.appspotmail.com
Fix commit: 6ebfad33161a packet: annotate data-races around ignore_outgoing
First crash: 64d, last: 64d
Discussions (9)
Title Replies (including bot) Last reply
[PATCH 5.4 172/183] packet: annotate data-races around ignore_outgoing 1 (1) 2024/03/24 23:46
[PATCH 5.10 223/238] packet: annotate data-races around ignore_outgoing 1 (1) 2024/03/24 23:40
[PATCH 5.15 296/317] packet: annotate data-races around ignore_outgoing 1 (1) 2024/03/24 23:34
[PATCH 6.1 415/451] packet: annotate data-races around ignore_outgoing 1 (1) 2024/03/24 23:11
[PATCH 6.6 600/638] packet: annotate data-races around ignore_outgoing 1 (1) 2024/03/24 23:00
[PATCH 6.7 671/713] packet: annotate data-races around ignore_outgoing 1 (1) 2024/03/24 22:46
[PATCH 6.8 671/715] packet: annotate data-races around ignore_outgoing 1 (1) 2024/03/24 22:34
[PATCH net] packet: annotate data-races around ignore_outgoing 6 (6) 2024/03/18 09:40
[syzbot] [net?] KCSAN: data-race in dev_queue_xmit_nit / packet_setsockopt 1 (2) 2024/03/14 14:09

Sample crash report:
==================================================================
BUG: KCSAN: data-race in dev_queue_xmit_nit / packet_setsockopt

write to 0xffff888107804542 of 1 bytes by task 22618 on cpu 0:
 packet_setsockopt+0xd83/0xfd0 net/packet/af_packet.c:4003
 do_sock_setsockopt net/socket.c:2311 [inline]
 __sys_setsockopt+0x1d8/0x250 net/socket.c:2334
 __do_sys_setsockopt net/socket.c:2343 [inline]
 __se_sys_setsockopt net/socket.c:2340 [inline]
 __x64_sys_setsockopt+0x66/0x80 net/socket.c:2340
 do_syscall_64+0xd3/0x1d0
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

read to 0xffff888107804542 of 1 bytes by task 27 on cpu 1:
 dev_queue_xmit_nit+0x82/0x620 net/core/dev.c:2248
 xmit_one net/core/dev.c:3527 [inline]
 dev_hard_start_xmit+0xcc/0x3f0 net/core/dev.c:3547
 __dev_queue_xmit+0xf24/0x1dd0 net/core/dev.c:4335
 dev_queue_xmit include/linux/netdevice.h:3091 [inline]
 batadv_send_skb_packet+0x264/0x300 net/batman-adv/send.c:108
 batadv_send_broadcast_skb+0x24/0x30 net/batman-adv/send.c:127
 batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:392 [inline]
 batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:420 [inline]
 batadv_iv_send_outstanding_bat_ogm_packet+0x3f0/0x4b0 net/batman-adv/bat_iv_ogm.c:1700
 process_one_work kernel/workqueue.c:3254 [inline]
 process_scheduled_works+0x465/0x990 kernel/workqueue.c:3335
 worker_thread+0x526/0x730 kernel/workqueue.c:3416
 kthread+0x1d1/0x210 kernel/kthread.c:388
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 27 Comm: kworker/u8:1 Tainted: G        W          6.8.0-syzkaller-08073-g480e035fc4c7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/03/14 10:02 upstream 480e035fc4c7 8d8ee116 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in dev_queue_xmit_nit / packet_setsockopt
* Struck through repros no longer work on HEAD.