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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 ffff888034147cb0 by task syz.1.675/8605

CPU: 0 UID: 0 PID: 8605 Comm: syz.1.675 Not tainted 6.16.0-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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/0x240 mm/kasan/report.c:482
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 __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:54
 free_poll_entry fs/select.c:132 [inline]
 poll_freewait+0xb1/0x240 fs/select.c:141
 do_select+0x172f/0x17e0 fs/select.c:608
 core_sys_select+0x6dd/0xa20 fs/select.c:677
 do_pselect fs/select.c:759 [inline]
 __do_sys_pselect6 fs/select.c:802 [inline]
 __se_sys_pselect6+0x27a/0x300 fs/select.c:793
 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
RIP: 0033:0x7f4e9918ebe9
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:00007f4e9a0a4038 EFLAGS: 00000246 ORIG_RAX: 000000000000010e
RAX: ffffffffffffffda RBX: 00007f4e993b6090 RCX: 00007f4e9918ebe9
RDX: 0000000000000000 RSI: 0000200000003800 RDI: 0000000000000040
RBP: 00007f4e99211e19 R08: 0000200000000240 R09: 0000000000000000
R10: 0000200000003880 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4e993b6128 R14: 00007f4e993b6090 R15: 00007ffdcd5bffd8
 </TASK>

Allocated by task 7486:
 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:4359
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 __comedi_device_postconfig_async drivers/comedi/drivers.c:667 [inline]
 __comedi_device_postconfig drivers/comedi/drivers.c:724 [inline]
 comedi_device_postconfig+0x4a8/0xc90 drivers/comedi/drivers.c:759
 comedi_device_attach+0x53a/0x670 drivers/comedi/drivers.c:1001
 do_devconfig_ioctl drivers/comedi/comedi_fops.c:855 [inline]
 comedi_unlocked_ioctl+0x686/0xfc0 drivers/comedi/comedi_fops.c:2156
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893
 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

Freed by task 8611:
 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:2381 [inline]
 slab_free mm/slub.c:4643 [inline]
 kfree+0x18e/0x440 mm/slub.c:4842
 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+0xbd2/0xfc0 drivers/comedi/comedi_fops.c:2156
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893
 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 ffff888034147c00
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 176 bytes inside of
 freed 256-byte region [ffff888034147c00, ffff888034147d00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888034147800 pfn:0x34146
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000240 ffff88801a441b40 ffffea0000cbd390 ffffea0000cbe590
raw: ffff888034147800 000000000010000a 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88801a441b40 ffffea0000cbd390 ffffea0000cbe590
head: ffff888034147800 000000000010000a 00000000f5000000 0000000000000000
head: 00fff00000000001 ffffea0000d05181 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 28990033243, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x21d5/0x22b0 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2451 [inline]
 allocate_slab+0x8a/0x3b0 mm/slub.c:2619
 new_slab mm/slub.c:2673 [inline]
 ___slab_alloc+0xbfc/0x1480 mm/slub.c:3859
 __slab_alloc mm/slub.c:3949 [inline]
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 __do_kmalloc_node mm/slub.c:4327 [inline]
 __kmalloc_node_track_caller_noprof+0x2f8/0x4e0 mm/slub.c:4347
 __do_krealloc mm/slub.c:4905 [inline]
 krealloc_noprof+0x124/0x340 mm/slub.c:4958
 add_sysfs_param+0xc9/0xa20 kernel/params.c:654
 kernel_add_sysfs_param+0xb4/0x130 kernel/params.c:811
 param_sysfs_builtin+0x1de/0x290 kernel/params.c:850
 param_sysfs_builtin_init+0x32/0x40 kernel/params.c:986
 do_one_initcall+0x233/0x820 init/main.c:1274
 do_initcall_level+0x137/0x1f0 init/main.c:1336
 do_initcalls+0x69/0xd0 init/main.c:1352
 kernel_init_freeable+0x3d9/0x570 init/main.c:1584
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888034147b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888034147c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888034147c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888034147d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888034147d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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