syzbot


KCSAN: data-race in console_callback / kbd_event (3)

Status: moderation: reported on 2024/06/03 17:49
Subsystems: serial
[Documentation on labels]
Reported-by: syzbot+a66efb2ca07765365aee@syzkaller.appspotmail.com
First crash: 14d, last: 14d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in console_callback / kbd_event (2) serial 1 948d 948d 0/27 auto-closed as invalid on 2021/12/18 10:16
upstream KCSAN: data-race in console_callback / kbd_event serial 1 1316d 1289d 0/27 auto-closed as invalid on 2020/12/21 11:59

Sample crash report:
==================================================================
BUG: KCSAN: data-race in console_callback / kbd_event

read to 0xffffffff88449ad0 of 4 bytes by task 20251 on cpu 1:
 console_callback+0x126/0x300 drivers/tty/vt/vt.c:3133
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3312
 worker_thread+0x526/0x730 kernel/workqueue.c:3393
 kthread+0x1d1/0x210 kernel/kthread.c:389
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

write to 0xffffffff88449ad0 of 4 bytes by task 26826 on cpu 0:
 kbd_event+0x1c05/0x1e90 drivers/tty/vt/keyboard.c:1548
 input_to_handler drivers/input/input.c:132 [inline]
 input_pass_values+0x3a5/0x790 drivers/input/input.c:161
 input_event_dispose+0x251/0x320 drivers/input/input.c:378
 input_handle_event+0xac4/0xb00 drivers/input/input.c:406
 input_inject_event+0xd1/0x100 drivers/input/input.c:465
 evdev_write+0x334/0x420 drivers/input/evdev.c:530
 vfs_write+0x28b/0x900 fs/read_write.c:588
 ksys_write+0xeb/0x1b0 fs/read_write.c:643
 __do_sys_write fs/read_write.c:655 [inline]
 __se_sys_write fs/read_write.c:652 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:652
 x64_sys_call+0x27ef/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000001 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 26826 Comm: syz-executor.3 Not tainted 6.10.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/03 17:49 upstream c3f38fa61af7 0aba2352 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in console_callback / kbd_event
* Struck through repros no longer work on HEAD.