Extracting prog: 2m36.657789487s
Minimizing prog: 9m1.350878104s
Simplifying prog options: 0s
Extracting C: 40.526789918s
Simplifying C: 10m22.975325914s


extracting reproducer from 1 programs
testing a last program of every proc
single: executing 1 programs separately with timeout 30s
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$comedi-epoll_create-epoll_ctl$EPOLL_CTL_ADD-ioctl$COMEDI_DEVCONFIG
detailed listing:
executing program 0:
r0 = openat$comedi(0xffffffffffffff9c, &(0x7f0000000040)='/dev/comedi4\x00', 0x181001, 0x0)
r1 = epoll_create(0x3)
epoll_ctl$EPOLL_CTL_ADD(r1, 0x1, r0, &(0x7f0000000080)={0x80000010})
ioctl$COMEDI_DEVCONFIG(r0, 0x40946400, 0x0)

program crashed: KASAN: slab-use-after-free Read in remove_wait_queue
single: successfully extracted reproducer
found reproducer with 4 syscalls
minimizing guilty program
testing program (duration=47.350167496s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$comedi-epoll_create-epoll_ctl$EPOLL_CTL_ADD
detailed listing:
executing program 0:
r0 = openat$comedi(0xffffffffffffff9c, &(0x7f0000000040)='/dev/comedi4\x00', 0x181001, 0x0)
r1 = epoll_create(0x3)
epoll_ctl$EPOLL_CTL_ADD(r1, 0x1, r0, &(0x7f0000000080)={0x80000010})

program did not crash
testing program (duration=47.350167496s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$comedi-epoll_create-ioctl$COMEDI_DEVCONFIG
detailed listing:
executing program 0:
r0 = openat$comedi(0xffffffffffffff9c, &(0x7f0000000040)='/dev/comedi4\x00', 0x181001, 0x0)
epoll_create(0x3)
ioctl$COMEDI_DEVCONFIG(r0, 0x40946400, 0x0)

program did not crash
testing program (duration=47.350167496s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$comedi-epoll_ctl$EPOLL_CTL_ADD-ioctl$COMEDI_DEVCONFIG
detailed listing:
executing program 0:
r0 = openat$comedi(0xffffffffffffff9c, &(0x7f0000000040)='/dev/comedi4\x00', 0x181001, 0x0)
epoll_ctl$EPOLL_CTL_ADD(0xffffffffffffffff, 0x1, r0, &(0x7f0000000080)={0x80000010})
ioctl$COMEDI_DEVCONFIG(r0, 0x40946400, 0x0)

program did not crash
testing program (duration=47.350167496s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): epoll_create-epoll_ctl$EPOLL_CTL_ADD-ioctl$COMEDI_DEVCONFIG
detailed listing:
executing program 0:
r0 = epoll_create(0x3)
epoll_ctl$EPOLL_CTL_ADD(r0, 0x1, 0xffffffffffffffff, &(0x7f0000000080)={0x80000010})
ioctl$COMEDI_DEVCONFIG(0xffffffffffffffff, 0x40946400, 0x0)

program did not crash
testing program (duration=47.350167496s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$comedi-epoll_create-epoll_ctl$EPOLL_CTL_ADD-ioctl$COMEDI_DEVCONFIG
detailed listing:
executing program 0:
r0 = openat$comedi(0xffffffffffffff9c, 0x0, 0x181001, 0x0)
r1 = epoll_create(0x3)
epoll_ctl$EPOLL_CTL_ADD(r1, 0x1, r0, &(0x7f0000000080)={0x80000010})
ioctl$COMEDI_DEVCONFIG(r0, 0x40946400, 0x0)

program did not crash
testing program (duration=47.350167496s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$comedi-epoll_create-epoll_ctl$EPOLL_CTL_ADD-ioctl$COMEDI_DEVCONFIG
detailed listing:
executing program 0:
r0 = openat$comedi(0xffffffffffffff9c, &(0x7f0000000040)='/dev/comedi4\x00', 0x181001, 0x0)
r1 = epoll_create(0x3)
epoll_ctl$EPOLL_CTL_ADD(r1, 0x1, r0, 0x0)
ioctl$COMEDI_DEVCONFIG(r0, 0x40946400, 0x0)

program did not crash
extracting C reproducer
testing compiled C program (duration=47.350167496s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$comedi-epoll_create-epoll_ctl$EPOLL_CTL_ADD-ioctl$COMEDI_DEVCONFIG
program crashed: KASAN: slab-use-after-free Read in remove_wait_queue
simplifying C reproducer
testing compiled C program (duration=47.350167496s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$comedi-epoll_create-epoll_ctl$EPOLL_CTL_ADD-ioctl$COMEDI_DEVCONFIG
program crashed: KASAN: slab-use-after-free Read in remove_wait_queue
testing compiled C program (duration=47.350167496s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$comedi-epoll_create-epoll_ctl$EPOLL_CTL_ADD-ioctl$COMEDI_DEVCONFIG
program crashed: KASAN: slab-use-after-free Read in remove_wait_queue
testing compiled C program (duration=47.350167496s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$comedi-epoll_create-epoll_ctl$EPOLL_CTL_ADD-ioctl$COMEDI_DEVCONFIG
program crashed: KASAN: slab-use-after-free Read in remove_wait_queue
testing compiled C program (duration=47.350167496s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$comedi-epoll_create-epoll_ctl$EPOLL_CTL_ADD-ioctl$COMEDI_DEVCONFIG
program crashed: KASAN: slab-use-after-free Read in remove_wait_queue
testing compiled C program (duration=47.350167496s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:false UseTmpDir:false HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$comedi-epoll_create-epoll_ctl$EPOLL_CTL_ADD-ioctl$COMEDI_DEVCONFIG
program crashed: KASAN: slab-use-after-free Read in remove_wait_queue
testing compiled C program (duration=47.350167496s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:false UseTmpDir:false HandleSegv:false Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$comedi-epoll_create-epoll_ctl$EPOLL_CTL_ADD-ioctl$COMEDI_DEVCONFIG
program crashed: KASAN: slab-use-after-free Read in remove_wait_queue
testing compiled C program (duration=47.350167496s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$comedi-epoll_create-epoll_ctl$EPOLL_CTL_ADD-ioctl$COMEDI_DEVCONFIG
program crashed: KASAN: slab-use-after-free Read in remove_wait_queue
testing program (duration=47.350167496s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$comedi-epoll_create-epoll_ctl$EPOLL_CTL_ADD-ioctl$COMEDI_DEVCONFIG
detailed listing:
executing program 0:
r0 = openat$comedi(0xffffffffffffff9c, &(0x7f0000000040)='/dev/comedi4\x00', 0x181001, 0x0)
r1 = epoll_create(0x3)
epoll_ctl$EPOLL_CTL_ADD(r1, 0x1, r0, &(0x7f0000000080)={0x80000010})
ioctl$COMEDI_DEVCONFIG(r0, 0x40946400, 0x0)

program crashed: KASAN: slab-use-after-free Read in remove_wait_queue
validation run: crashed=true
testing program (duration=47.350167496s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$comedi-epoll_create-epoll_ctl$EPOLL_CTL_ADD-ioctl$COMEDI_DEVCONFIG
detailed listing:
executing program 0:
r0 = openat$comedi(0xffffffffffffff9c, &(0x7f0000000040)='/dev/comedi4\x00', 0x181001, 0x0)
r1 = epoll_create(0x3)
epoll_ctl$EPOLL_CTL_ADD(r1, 0x1, r0, &(0x7f0000000080)={0x80000010})
ioctl$COMEDI_DEVCONFIG(r0, 0x40946400, 0x0)

program crashed: KASAN: slab-use-after-free Read in remove_wait_queue
validation run: crashed=true
testing program (duration=47.350167496s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$comedi-epoll_create-epoll_ctl$EPOLL_CTL_ADD-ioctl$COMEDI_DEVCONFIG
detailed listing:
executing program 0:
r0 = openat$comedi(0xffffffffffffff9c, &(0x7f0000000040)='/dev/comedi4\x00', 0x181001, 0x0)
r1 = epoll_create(0x3)
epoll_ctl$EPOLL_CTL_ADD(r1, 0x1, r0, &(0x7f0000000080)={0x80000010})
ioctl$COMEDI_DEVCONFIG(r0, 0x40946400, 0x0)

program crashed: KASAN: slab-use-after-free Read in remove_wait_queue
validation run: crashed=true
reproducing took 27m33.971014625s
repro crashed as (corrupted=false):
==================================================================
BUG: KASAN: slab-use-after-free in __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
BUG: KASAN: slab-use-after-free in _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
Read of size 1 at addr ffff88814bf674b0 by task syz.0.16/6035

CPU: 0 UID: 0 PID: 6035 Comm: syz.0.16 Not tainted 6.16.0-rc5-next-20250709-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x230 mm/kasan/report.c:480
 kasan_report+0x118/0x150 mm/kasan/report.c:593
 __kasan_check_byte+0x2a/0x40 mm/kasan/common.c:557
 kasan_check_byte include/linux/kasan.h:399 [inline]
 lock_acquire+0x8d/0x360 kernel/locking/lockdep.c:5845
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
 remove_wait_queue+0x24/0x120 kernel/sched/wait.c:73
 ep_remove_wait_queue fs/eventpoll.c:679 [inline]
 ep_unregister_pollwait+0x153/0x240 fs/eventpoll.c:694
 ep_clear_and_put+0xed/0x3a0 fs/eventpoll.c:860
 ep_eventpoll_release+0x45/0x60 fs/eventpoll.c:912
 __fput+0x44c/0xa70 fs/file_table.c:468
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc14478e929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe6ffd3238 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00000000000195ba RCX: 00007fc14478e929
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000001 R09: 000000046ffd352f
R10: 00007fc144600000 R11: 0000000000000246 R12: 00007fc1449b5fac
R13: 00007fc1449b5fa0 R14: ffffffffffffffff R15: 0000000000000003
 </TASK>

Allocated by task 1:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4396
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 __comedi_device_postconfig_async drivers/comedi/drivers.c:664 [inline]
 __comedi_device_postconfig drivers/comedi/drivers.c:721 [inline]
 comedi_device_postconfig+0x4a8/0xc90 drivers/comedi/drivers.c:756
 comedi_auto_config+0x267/0x380 drivers/comedi/drivers.c:1069
 comedi_test_init+0x8e/0x110 drivers/comedi/drivers/comedi_test.c:836
 do_one_initcall+0x233/0x820 init/main.c:1269
 do_initcall_level+0x137/0x1f0 init/main.c:1331
 do_initcalls+0x69/0xd0 init/main.c:1347
 kernel_init_freeable+0x3d9/0x590 init/main.c:1579
 kernel_init+0x1d/0x1d0 init/main.c:1469
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Freed by task 6035:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2417 [inline]
 slab_free mm/slub.c:4680 [inline]
 kfree+0x18e/0x440 mm/slub.c:4879
 comedi_device_detach_cleanup drivers/comedi/drivers.c:171 [inline]
 comedi_device_detach+0x372/0x720 drivers/comedi/drivers.c:208
 do_devconfig_ioctl drivers/comedi/comedi_fops.c:833 [inline]
 comedi_unlocked_ioctl+0xc4b/0xf40 drivers/comedi/comedi_fops.c:2136
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:598 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:584
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88814bf67400
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 176 bytes inside of
 freed 256-byte region [ffff88814bf67400, ffff88814bf67500)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x14bf66
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x57ff00000000040(head|node=1|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 057ff00000000040 ffff88801a841b40 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 057ff00000000040 ffff88801a841b40 dead000000000122 0000000000000000
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 057ff00000000001 ffffea00052fd981 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 22769355099, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1848
 prep_new_page mm/page_alloc.c:1856 [inline]
 get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3855
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5145
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:2487 [inline]
 allocate_slab+0x8a/0x370 mm/slub.c:2655
 new_slab mm/slub.c:2709 [inline]
 ___slab_alloc+0xbeb/0x1410 mm/slub.c:3891
 __slab_alloc mm/slub.c:3981 [inline]
 __slab_alloc_node mm/slub.c:4056 [inline]
 slab_alloc_node mm/slub.c:4217 [inline]
 __kmalloc_cache_noprof+0x296/0x3d0 mm/slub.c:4391
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 bus_add_driver+0x162/0x640 drivers/base/bus.c:662
 driver_register+0x23a/0x320 drivers/base/driver.c:249
 __hid_register_driver+0x12a/0x170 drivers/hid/hid-core.c:3038
 pyra_init+0x44/0x80 drivers/hid/hid-roccat-pyra.c:595
 do_one_initcall+0x233/0x820 init/main.c:1269
 do_initcall_level+0x137/0x1f0 init/main.c:1331
 do_initcalls+0x69/0xd0 init/main.c:1347
 kernel_init_freeable+0x3d9/0x590 init/main.c:1579
 kernel_init+0x1d/0x1d0 init/main.c:1469
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88814bf67380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88814bf67400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88814bf67480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff88814bf67500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88814bf67580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

final repro crashed as (corrupted=false):
==================================================================
BUG: KASAN: slab-use-after-free in __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
BUG: KASAN: slab-use-after-free in _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
Read of size 1 at addr ffff88814bf674b0 by task syz.0.16/6035

CPU: 0 UID: 0 PID: 6035 Comm: syz.0.16 Not tainted 6.16.0-rc5-next-20250709-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x230 mm/kasan/report.c:480
 kasan_report+0x118/0x150 mm/kasan/report.c:593
 __kasan_check_byte+0x2a/0x40 mm/kasan/common.c:557
 kasan_check_byte include/linux/kasan.h:399 [inline]
 lock_acquire+0x8d/0x360 kernel/locking/lockdep.c:5845
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
 remove_wait_queue+0x24/0x120 kernel/sched/wait.c:73
 ep_remove_wait_queue fs/eventpoll.c:679 [inline]
 ep_unregister_pollwait+0x153/0x240 fs/eventpoll.c:694
 ep_clear_and_put+0xed/0x3a0 fs/eventpoll.c:860
 ep_eventpoll_release+0x45/0x60 fs/eventpoll.c:912
 __fput+0x44c/0xa70 fs/file_table.c:468
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc14478e929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe6ffd3238 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00000000000195ba RCX: 00007fc14478e929
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000001 R09: 000000046ffd352f
R10: 00007fc144600000 R11: 0000000000000246 R12: 00007fc1449b5fac
R13: 00007fc1449b5fa0 R14: ffffffffffffffff R15: 0000000000000003
 </TASK>

Allocated by task 1:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4396
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 __comedi_device_postconfig_async drivers/comedi/drivers.c:664 [inline]
 __comedi_device_postconfig drivers/comedi/drivers.c:721 [inline]
 comedi_device_postconfig+0x4a8/0xc90 drivers/comedi/drivers.c:756
 comedi_auto_config+0x267/0x380 drivers/comedi/drivers.c:1069
 comedi_test_init+0x8e/0x110 drivers/comedi/drivers/comedi_test.c:836
 do_one_initcall+0x233/0x820 init/main.c:1269
 do_initcall_level+0x137/0x1f0 init/main.c:1331
 do_initcalls+0x69/0xd0 init/main.c:1347
 kernel_init_freeable+0x3d9/0x590 init/main.c:1579
 kernel_init+0x1d/0x1d0 init/main.c:1469
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Freed by task 6035:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2417 [inline]
 slab_free mm/slub.c:4680 [inline]
 kfree+0x18e/0x440 mm/slub.c:4879
 comedi_device_detach_cleanup drivers/comedi/drivers.c:171 [inline]
 comedi_device_detach+0x372/0x720 drivers/comedi/drivers.c:208
 do_devconfig_ioctl drivers/comedi/comedi_fops.c:833 [inline]
 comedi_unlocked_ioctl+0xc4b/0xf40 drivers/comedi/comedi_fops.c:2136
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:598 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:584
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88814bf67400
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 176 bytes inside of
 freed 256-byte region [ffff88814bf67400, ffff88814bf67500)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x14bf66
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x57ff00000000040(head|node=1|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 057ff00000000040 ffff88801a841b40 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 057ff00000000040 ffff88801a841b40 dead000000000122 0000000000000000
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 057ff00000000001 ffffea00052fd981 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 22769355099, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1848
 prep_new_page mm/page_alloc.c:1856 [inline]
 get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3855
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5145
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:2487 [inline]
 allocate_slab+0x8a/0x370 mm/slub.c:2655
 new_slab mm/slub.c:2709 [inline]
 ___slab_alloc+0xbeb/0x1410 mm/slub.c:3891
 __slab_alloc mm/slub.c:3981 [inline]
 __slab_alloc_node mm/slub.c:4056 [inline]
 slab_alloc_node mm/slub.c:4217 [inline]
 __kmalloc_cache_noprof+0x296/0x3d0 mm/slub.c:4391
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 bus_add_driver+0x162/0x640 drivers/base/bus.c:662
 driver_register+0x23a/0x320 drivers/base/driver.c:249
 __hid_register_driver+0x12a/0x170 drivers/hid/hid-core.c:3038
 pyra_init+0x44/0x80 drivers/hid/hid-roccat-pyra.c:595
 do_one_initcall+0x233/0x820 init/main.c:1269
 do_initcall_level+0x137/0x1f0 init/main.c:1331
 do_initcalls+0x69/0xd0 init/main.c:1347
 kernel_init_freeable+0x3d9/0x590 init/main.c:1579
 kernel_init+0x1d/0x1d0 init/main.c:1469
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88814bf67380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88814bf67400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88814bf67480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff88814bf67500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88814bf67580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================