syzbot


KCSAN: data-race in can_receive / can_stat_update (4)

Status: auto-closed as invalid on 2022/08/22 20:20
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 150d, last: 137d
similar bugs (4):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in can_receive / can_stat_update (2) 1 612d 612d 0/24 auto-closed as invalid on 2021/05/04 12:50
upstream KCSAN: data-race in can_receive / can_stat_update (3) 5 191d 265d 0/24 auto-closed as invalid on 2022/06/29 13:32
upstream KCSAN: data-race in can_receive / can_stat_update 3 1037d 1060d 0/24 auto-closed as invalid on 2020/04/09 06:18
upstream KCSAN: data-race in can_receive / can_stat_update (5) 1 92d 92d 0/24 auto-closed as invalid on 2022/10/06 14:19

Sample crash report:
==================================================================
BUG: KCSAN: data-race in can_receive / can_stat_update

read to 0xffff888125b24be8 of 8 bytes by interrupt on cpu 0:
 can_stat_update+0x481/0x6f0 net/can/proc.c:152
 call_timer_fn+0x2e/0x240 kernel/time/timer.c:1474
 expire_timers+0x116/0x240 kernel/time/timer.c:1519
 __run_timers+0x350/0x400 kernel/time/timer.c:1790
 run_timer_softirq+0x2e/0x60 kernel/time/timer.c:1803
 __do_softirq+0x158/0x2e3 kernel/softirq.c:571
 run_ksoftirqd+0x1f/0x30 kernel/softirq.c:934
 smpboot_thread_fn+0x308/0x4a0 kernel/smpboot.c:164
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

read-write to 0xffff888125b24be8 of 8 bytes by interrupt on cpu 1:
 can_receive+0x62/0x1f0 net/can/af_can.c:652
 canfd_rcv+0x9e/0x170 net/can/af_can.c:722
 __netif_receive_skb_one_core net/core/dev.c:5484 [inline]
 __netif_receive_skb+0x8b/0x1b0 net/core/dev.c:5598
 process_backlog+0x23f/0x3b0 net/core/dev.c:5926
 __napi_poll+0x65/0x390 net/core/dev.c:6492
 napi_poll net/core/dev.c:6559 [inline]
 net_rx_action+0x37e/0x730 net/core/dev.c:6670
 __do_softirq+0x158/0x2e3 kernel/softirq.c:571
 run_ksoftirqd+0x1f/0x30 kernel/softirq.c:934
 smpboot_thread_fn+0x308/0x4a0 kernel/smpboot.c:164
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

value changed: 0x0000000000000527 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 19 Comm: ksoftirqd/1 Not tainted 5.19.0-rc7-syzkaller-00002-g80e19f34c288-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022
==================================================================

Crashes (2):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2022/07/18 20:13 upstream 80e19f34c288 ff988920 .config log report info KCSAN: data-race in can_receive / can_stat_update
ci2-upstream-kcsan-gce 2022/07/05 14:30 upstream c1084b6c5620 bff65f44 .config log report info KCSAN: data-race in can_receive / can_stat_update
* Struck through repros no longer work on HEAD.