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KCSAN: data-race in exit_signals / kthread_stop (2)

Status: auto-closed as invalid on 2021/05/17 09:01
Subsystems: kernel
[Documentation on labels]
First crash: 1088d, last: 1088d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in exit_signals / kthread_stop kernel 2 1143d 1158d 0/26 auto-closed as invalid on 2021/03/16 14:08

Sample crash report:
vhci_hcd: stop threads
vhci_hcd: release socket
vhci_hcd: disconnect device
==================================================================
BUG: KCSAN: data-race in exit_signals / kthread_stop

write to 0xffff888105f9e02c of 4 bytes by task 8809 on cpu 0:
 exit_signals+0x118/0x550 kernel/signal.c:2873
 do_exit+0x197/0x15e0 kernel/exit.c:781
 kthread+0x213/0x230 kernel/kthread.c:294
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

read to 0xffff888105f9e02c of 4 bytes by task 24 on cpu 1:
 to_kthread kernel/kthread.c:83 [inline]
 kthread_stop+0x5f/0x2c0 kernel/kthread.c:617
 vhci_shutdown_connection+0x68/0x680 drivers/usb/usbip/vhci_hcd.c:1021
 event_handler+0x185/0x340 drivers/usb/usbip/usbip_event.c:78
 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

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 24 Comm: kworker/u4:1 Not tainted 5.12.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: usbip_event event_handler
==================================================================
vhci_hcd: stop threads
vhci_hcd: release socket
vhci_hcd: disconnect device
vhci_hcd: stop threads
vhci_hcd: release socket
vhci_hcd: disconnect device
vhci_hcd: stop threads
vhci_hcd: release socket
vhci_hcd: disconnect device
vhci_hcd: stop threads
vhci_hcd: release socket
vhci_hcd: disconnect device
vhci_hcd: stop threads
vhci_hcd: release socket
vhci_hcd: disconnect device
vhci_hcd: stop threads
vhci_hcd: release socket
vhci_hcd: disconnect device
vhci_hcd: stop threads
vhci_hcd: release socket
vhci_hcd: disconnect device
vhci_hcd: stop threads
vhci_hcd: release socket
vhci_hcd: disconnect device

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/04/05 12:03 upstream e49d033bddf5 6a81331a .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in exit_signals / kthread_stop
* Struck through repros no longer work on HEAD.