KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt

Status: moderation: reported on 2026/07/24 18:43
Subsystems: input
Labels: race:benign prio:low
[Documentation on labels]
Reported-by: syzbot+96605ccb04166cb6cfe8@syzkaller.appspotmail.com
First crash: 32d, last: 1h40m
✨ AI Jobs (2)
ID Workflow Result Correct Bug Created Started Finished Revision
a54ac6e2 assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt 2026/07/26 01:50 2026/07/26 01:50 2026/07/26 02:20 492bab15
f55a2969 assessment-kcsan Benign: ✅ KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt 2026/07/24 18:42 2026/07/24 18:42 2026/07/24 18:45 1bdb5c57

Sample crash report:
==================================================================
BUG: KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt

write to 0xffff8881026d6c48 of 8 bytes by interrupt on cpu 0:
 ps2_interrupt+0x50d/0x550 drivers/input/serio/libps2.c:-1
 serio_interrupt+0x63/0xe0 drivers/input/serio/serio.c:967
 i8042_handle_data+0x36c/0x650 drivers/input/serio/i8042.c:598
 i8042_interrupt+0x15/0x90 drivers/input/serio/i8042.c:605
 __handle_irq_event_percpu+0x8b/0x480 kernel/irq/handle.c:209
 handle_irq_event_percpu kernel/irq/handle.c:246 [inline]
 handle_irq_event+0x64/0xf0 kernel/irq/handle.c:263
 handle_edge_irq+0x155/0x440 kernel/irq/chip.c:859
 generic_handle_irq_desc include/linux/irqdesc.h:188 [inline]
 handle_irq arch/x86/kernel/irq.c:209 [inline]
 call_irq_handler arch/x86/kernel/irq.c:-1 [inline]
 __common_interrupt+0x60/0xb0 arch/x86/kernel/irq.c:280
 common_interrupt+0x7e/0x90 arch/x86/kernel/irq.c:273
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:665
 native_irq_enable arch/x86/include/asm/irqflags.h:-1 [inline]
 arch_local_irq_enable arch/x86/include/asm/irqflags.h:119 [inline]
 handle_softirqs+0x7f/0x2a0 kernel/softirq.c:629
 __do_softirq kernel/softirq.c:679 [inline]
 invoke_softirq kernel/softirq.c:519 [inline]
 __irq_exit_rcu+0x44/0xe0 kernel/softirq.c:767
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0x37/0x80 arch/x86/kernel/apic/apic.c:1062
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674

read to 0xffff8881026d6c48 of 8 bytes by task 3081 on cpu 1:
 ps2_do_sendbyte+0x10b/0x320 drivers/input/serio/libps2.c:65
 __ps2_command+0x364/0xaa0 drivers/input/serio/libps2.c:322
 ps2_command+0x52/0x90 drivers/input/serio/libps2.c:403
 alps_rpt_cmd+0x7a/0x150 drivers/input/mouse/alps.c:1780
 alps_identify+0x151/0x5e0 drivers/input/mouse/alps.c:2909
 alps_detect+0x31/0x250 drivers/input/mouse/alps.c:3182
 psmouse_do_detect drivers/input/mouse/psmouse-base.c:995 [inline]
 psmouse_try_protocol drivers/input/mouse/psmouse-base.c:1009 [inline]
 psmouse_extensions+0x5e6/0x960 drivers/input/mouse/psmouse-base.c:1140
 __psmouse_reconnect+0x3dd/0x880 drivers/input/mouse/psmouse-base.c:1685
 psmouse_reconnect+0x23/0x40 drivers/input/mouse/psmouse-base.c:1723
 serio_reconnect_driver drivers/input/serio/serio.c:52 [inline]
 serio_reconnect_port drivers/input/serio/serio.c:558 [inline]
 serio_handle_event+0x1bc/0x990 drivers/input/serio/serio.c:201
 process_one_work kernel/workqueue.c:3387 [inline]
 process_scheduled_works+0x56a/0xa50 kernel/workqueue.c:3470
 worker_thread+0x569/0x750 kernel/workqueue.c:3551
 kthread+0x223/0x270 kernel/kthread.c:436
 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x0000000000000001 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3081 Comm: kworker/1:2 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: events_long serio_handle_event
==================================================================

Crashes (30):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/25 21:22 upstream 73ae59e97596 a9a1fc32 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/08/25 16:49 upstream 66498c75b4f8 a9a1fc32 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/08/25 08:39 upstream 66498c75b4f8 614e416a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/08/25 08:38 upstream 66498c75b4f8 614e416a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/08/17 10:06 upstream 8d3ae59288f1 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/08/12 00:11 upstream f5bbbfec59b4 71790083 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/08/09 20:30 upstream b9b3e33b70b7 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/08/08 22:08 upstream a7c7074b58d2 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/08/06 02:40 upstream 0d8395707651 cd5b1963 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/08/05 07:09 upstream c21bb4193868 52aa2820 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/08/04 21:33 upstream 562bfb501c54 d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/08/04 15:54 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/08/02 23:50 upstream bd1dde877520 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/08/02 08:38 upstream 2d2338c93da7 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/08/02 04:15 upstream 02dc699f83d0 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/08/01 07:10 upstream 0131b508c0e2 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/08/01 07:09 upstream 0131b508c0e2 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/07/31 04:48 upstream 3708dd948844 aaffb173 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/07/28 05:31 upstream 62cc90241548 45ae1df4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/07/27 15:41 upstream f5098b6bae76 aae9036b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/07/27 15:38 upstream f5098b6bae76 aae9036b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/07/27 10:31 upstream f5098b6bae76 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/07/27 03:03 upstream 4235cb24ec1e 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/07/26 09:55 upstream 3dab139d4795 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/07/26 06:08 upstream 0ce37745d4bf 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/07/26 06:06 upstream 0ce37745d4bf 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/07/26 06:01 upstream 0ce37745d4bf 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/07/26 00:27 upstream 0ce37745d4bf 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/07/25 10:11 upstream e2a936998ab2 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
2026/07/24 18:42 upstream 48a5a7ab8d6a dd737a83 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in ps2_do_sendbyte / ps2_interrupt
* Struck through repros no longer work on HEAD.