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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 ffff888032bf38b0 by task syz-executor238/5874

CPU: 0 UID: 0 PID: 5874 Comm: syz-executor238 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: 0033:0x7f7a9cb85b49
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 71 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe8de9e5b8 EFLAGS: 00000212 ORIG_RAX: 000000000000010e
RAX: ffffffffffffffda RBX: 00007ffe8de9e600 RCX: 00007f7a9cb85b49
RDX: 0000000000000000 RSI: 00002000000001c0 RDI: 0000000000000040
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 00002000000002c0 R11: 0000000000000212 R12: 00000000000f4240
R13: 000000000001a81d R14: 00007ffe8de9e5ec R15: 00007ffe8de9e5f0
 </TASK>

Allocated by task 5876:
 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 5878:
 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 ffff888032bf3800
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 176 bytes inside of
 freed 256-byte region [ffff888032bf3800, ffff888032bf3900)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x32bf2
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801a441b40 ffffea00009cc800 dead000000000002
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801a441b40 ffffea00009cc800 dead000000000002
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000001 ffffea0000cafc81 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5208, tgid 5208 (udevadm), ts 35204432609, free_ts 27252253057
 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]
 __kmalloc_cache_noprof+0x296/0x3d0 mm/slub.c:4354
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 smk_fetch+0x95/0x140 security/smack/smack_lsm.c:285
 smack_d_instantiate+0x837/0x940 security/smack/smack_lsm.c:3641
 security_d_instantiate+0x10a/0x200 security/security.c:4079
 d_splice_alias+0x6e/0x330 fs/dcache.c:2997
 __lookup_slow+0x297/0x3d0 fs/namei.c:1817
 lookup_slow+0x53/0x70 fs/namei.c:1834
 walk_component+0x2d2/0x400 fs/namei.c:2138
 lookup_last fs/namei.c:2639 [inline]
 path_lookupat+0x163/0x430 fs/namei.c:2663
 filename_lookup+0x212/0x570 fs/namei.c:2692
page last free pid 10 tgid 10 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0xc65/0xe60 mm/page_alloc.c:2706
 vfree+0x25a/0x400 mm/vmalloc.c:3434
 delayed_vfree_work+0x55/0x80 mm/vmalloc.c:3353
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff888032bf3780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888032bf3800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888032bf3880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888032bf3900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888032bf3980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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