KCSAN: data-race in add_input_randomness / add_input_randomness (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: fa02fcd9 Merge tag 'media/v5.10-2' of git://git.kernel.org..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=108e21ae500000
kernel config: https://syzkaller.appspot.com/x/.config?x=9b9b19d1bde60f8d
dashboard link: https://syzkaller.appspot.com/bug?extid=2ccfc09f966037843ba8
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project.git 913f6005669cfb590c99865a90bc51ed0983d09d)
CC: [linux-...@vger.kernel.org ty...@mit.edu]

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2ccfc0...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in add_input_randomness / add_input_randomness

write to 0xffffffff88be6aa4 of 1 bytes by interrupt on cpu 1:
add_input_randomness+0x66/0x2a0 drivers/char/random.c:1210
input_handle_event+0x9b1/0xd30 drivers/input/input.c:373
input_event+0x7d/0xa0 drivers/input/input.c:441
hidinput_hid_event+0xa84/0xb90 drivers/hid/hid-input.c:1399
hid_process_event+0x2f3/0x3c0 drivers/hid/hid-core.c:1519
hid_input_field drivers/hid/hid-core.c:1577 [inline]
hid_report_raw_event+0xb96/0xd60 drivers/hid/hid-core.c:1783
hid_input_report+0x2c9/0x330 drivers/hid/hid-core.c:1850
hid_irq_in+0x2cb/0x3d0 drivers/hid/usbhid/hid-core.c:284
__usb_hcd_giveback_urb+0x219/0x290 drivers/usb/core/hcd.c:1650
usb_hcd_giveback_urb+0xae/0x210 drivers/usb/core/hcd.c:1716
dummy_timer+0x4d3/0x2390 drivers/usb/gadget/udc/dummy_hcd.c:1967
call_timer_fn+0x2e/0x240 kernel/time/timer.c:1410
expire_timers+0x116/0x260 kernel/time/timer.c:1455
__run_timers+0x338/0x3d0 kernel/time/timer.c:1747
run_timer_softirq+0x19/0x30 kernel/time/timer.c:1760
__do_softirq+0x12c/0x2b1 kernel/softirq.c:298
asm_call_irq_on_stack+0xf/0x20
__run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline]
run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline]
do_softirq_own_stack+0x32/0x40 arch/x86/kernel/irq_64.c:77
invoke_softirq kernel/softirq.c:393 [inline]
__irq_exit_rcu+0xb2/0xc0 kernel/softirq.c:423
sysvec_apic_timer_interrupt+0x74/0x90 arch/x86/kernel/apic/apic.c:1091
asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631
native_safe_halt arch/x86/include/asm/irqflags.h:60 [inline]
arch_safe_halt arch/x86/include/asm/irqflags.h:103 [inline]
acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline]
acpi_idle_do_entry drivers/acpi/processor_idle.c:517 [inline]
acpi_idle_enter+0x25b/0x2e0 drivers/acpi/processor_idle.c:648
cpuidle_enter_state+0x2bd/0x750 drivers/cpuidle/cpuidle.c:237
cpuidle_enter+0x3c/0x60 drivers/cpuidle/cpuidle.c:351
call_cpuidle kernel/sched/idle.c:132 [inline]
cpuidle_idle_call kernel/sched/idle.c:213 [inline]
do_idle+0x193/0x230 kernel/sched/idle.c:273
cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:369
secondary_startup_64_no_verify+0xb0/0xbb

read to 0xffffffff88be6aa4 of 1 bytes by interrupt on cpu 0:
add_input_randomness+0x35/0x2a0 drivers/char/random.c:1207
input_handle_event+0x9b1/0xd30 drivers/input/input.c:373
input_event+0x7d/0xa0 drivers/input/input.c:441
hidinput_hid_event+0xa84/0xb90 drivers/hid/hid-input.c:1399
hid_process_event+0x2f3/0x3c0 drivers/hid/hid-core.c:1519
hid_input_field drivers/hid/hid-core.c:1577 [inline]
hid_report_raw_event+0xb96/0xd60 drivers/hid/hid-core.c:1783
hid_input_report+0x2c9/0x330 drivers/hid/hid-core.c:1850
hid_irq_in+0x2cb/0x3d0 drivers/hid/usbhid/hid-core.c:284
__usb_hcd_giveback_urb+0x219/0x290 drivers/usb/core/hcd.c:1650
usb_hcd_giveback_urb+0xae/0x210 drivers/usb/core/hcd.c:1716
dummy_timer+0x4d3/0x2390 drivers/usb/gadget/udc/dummy_hcd.c:1967
call_timer_fn+0x2e/0x240 kernel/time/timer.c:1410
expire_timers+0x116/0x260 kernel/time/timer.c:1455
__run_timers+0x338/0x3d0 kernel/time/timer.c:1747
run_timer_softirq+0x19/0x30 kernel/time/timer.c:1760
__do_softirq+0x12c/0x2b1 kernel/softirq.c:298
asm_call_irq_on_stack+0xf/0x20
__run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline]
run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline]
do_softirq_own_stack+0x32/0x40 arch/x86/kernel/irq_64.c:77
invoke_softirq kernel/softirq.c:393 [inline]
__irq_exit_rcu+0xb2/0xc0 kernel/softirq.c:423
sysvec_apic_timer_interrupt+0x74/0x90 arch/x86/kernel/apic/apic.c:1091
asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631
native_safe_halt arch/x86/include/asm/irqflags.h:60 [inline]
arch_safe_halt arch/x86/include/asm/irqflags.h:103 [inline]
acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline]
acpi_idle_do_entry drivers/acpi/processor_idle.c:517 [inline]
acpi_idle_enter+0x25b/0x2e0 drivers/acpi/processor_idle.c:648
cpuidle_enter_state+0x2bd/0x750 drivers/cpuidle/cpuidle.c:237
cpuidle_enter+0x3c/0x60 drivers/cpuidle/cpuidle.c:351
call_cpuidle kernel/sched/idle.c:132 [inline]
cpuidle_idle_call kernel/sched/idle.c:213 [inline]
do_idle+0x193/0x230 kernel/sched/idle.c:273
cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:369
rest_init+0xd7/0xe0 init/main.c:721
arch_call_rest_init+0xa/0xb
start_kernel+0x5a0/0x625 init/main.c:1061
secondary_startup_64_no_verify+0xb0/0xbb

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.10.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.