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BUG: KCSAN: data-race in __ps2_command / ps2_interrupt

write to 0xffff888103bf5858 of 1 bytes by interrupt on cpu 0:
 ps2_handle_response drivers/input/serio/libps2.c:479 [inline]
 ps2_interrupt+0x1be/0x550 drivers/input/serio/libps2.c:608
 serio_interrupt+0x66/0xf0 drivers/input/serio/serio.c:967
 i8042_handle_data+0x388/0x680 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]
 do_user_addr_fault+0x139/0xde0 arch/x86/mm/fault.c:1288
 handle_page_fault arch/x86/mm/fault.c:1483 [inline]
 exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1536
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
 rep_movs_alternative+0x4a/0xa0 arch/x86/lib/copy_user_64.S:68
 copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline]
 raw_copy_from_user arch/x86/include/asm/uaccess_64.h:141 [inline]
 copy_from_user_iter lib/iov_iter.c:67 [inline]
 iterate_ubuf include/linux/iov_iter.h:30 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:302 [inline]
 iterate_and_advance include/linux/iov_iter.h:330 [inline]
 __copy_from_iter lib/iov_iter.c:261 [inline]
 _copy_from_iter+0x114/0xe70 lib/iov_iter.c:272
 copy_from_iter include/linux/uio.h:228 [inline]
 copy_from_iter_full include/linux/uio.h:245 [inline]
 do_copy_data_nocache net/mptcp/protocol.c:1955 [inline]
 mptcp_sendmsg+0x91c/0x1110 net/mptcp/protocol.c:2079
 inet6_sendmsg+0xc5/0xd0 net/ipv6/af_inet6.c:638
 sock_sendmsg_nosec net/socket.c:800 [inline]
 __sock_sendmsg net/socket.c:818 [inline]
 ____sys_sendmsg+0x390/0x590 net/socket.c:2715
 ___sys_sendmsg+0x195/0x1e0 net/socket.c:2769
 __sys_sendmsg net/socket.c:2801 [inline]
 __do_sys_sendmsg net/socket.c:2806 [inline]
 __se_sys_sendmsg net/socket.c:2804 [inline]
 __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2804
 x64_sys_call+0x22ab/0x2550 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888103bf5858 of 1 bytes by task 4733 on cpu 1:
 __ps2_command+0x589/0xa90 drivers/input/serio/libps2.c:343
 ps2_command+0x52/0x90 drivers/input/serio/libps2.c:403
 cypress_send_ext_cmd+0xba/0x550 drivers/input/mouse/cypress_ps2.c:142
 cypress_detect+0x44/0x130 drivers/input/mouse/cypress_ps2.c:163
 psmouse_do_detect drivers/input/mouse/psmouse-base.c:995 [inline]
 psmouse_try_protocol drivers/input/mouse/psmouse-base.c:1009 [inline]
 psmouse_extensions+0x48c/0x960 drivers/input/mouse/psmouse-base.c:1132
 psmouse_switch_protocol+0x8b/0x300 drivers/input/mouse/psmouse-base.c:1513
 psmouse_attr_set_protocol+0x462/0xad0 drivers/input/mouse/psmouse-base.c:1918
 psmouse_attr_set_helper+0x2a3/0x450 drivers/input/mouse/psmouse-base.c:1815
 dev_attr_store+0x4a/0x70 drivers/base/core.c:2509
 sysfs_kf_write+0xfe/0x120 fs/sysfs/file.c:145
 kernfs_fop_write_iter+0x1d2/0x2e0 fs/kernfs/file.c:345
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x57a/0x990 fs/read_write.c:687
 ksys_write+0xdc/0x1a0 fs/read_write.c:739
 __do_sys_write fs/read_write.c:750 [inline]
 __se_sys_write fs/read_write.c:747 [inline]
 __x64_sys_write+0x40/0x50 fs/read_write.c:747
 x64_sys_call+0x154e/0x2550 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x02 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 4733 Comm: syz.3.273 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
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input: ImExPS/2 Generic Explorer Mouse as /devices/platform/i8042/serio1/input/input5