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BUG: KASAN: slab-use-after-free in sysfs_remove_file_ns+0x63/0x70 fs/sysfs/file.c:510
Read of size 8 at addr ffff888033cfca30 by task syz.0.5582/28158

CPU: 0 UID: 0 PID: 28158 Comm: syz.0.5582 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xcd/0x630 mm/kasan/report.c:482
 kasan_report+0xe0/0x110 mm/kasan/report.c:595
 sysfs_remove_file_ns+0x63/0x70 fs/sysfs/file.c:510
 sysfs_remove_file include/linux/sysfs.h:770 [inline]
 driver_remove_file drivers/base/driver.c:201 [inline]
 driver_remove_file+0x4a/0x60 drivers/base/driver.c:197
 remove_bind_files drivers/base/bus.c:605 [inline]
 bus_remove_driver+0x224/0x2c0 drivers/base/bus.c:743
 driver_unregister+0x76/0xb0 drivers/base/driver.c:277
 comedi_device_detach_locked+0x12f/0xa50 drivers/comedi/drivers.c:207
 do_devconfig_ioctl+0x555/0x710 drivers/comedi/comedi_fops.c:848
 comedi_unlocked_ioctl+0x165d/0x2f00 drivers/comedi/comedi_fops.c:2178
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl fs/ioctl.c:583 [inline]
 __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0f6198efc9
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:00007f0f628b0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f0f61be5fa0 RCX: 00007f0f6198efc9
RDX: 0000000000000000 RSI: 0000000040946400 RDI: 0000000000000003
RBP: 00007f0f61a11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0f61be6038 R14: 00007f0f61be5fa0 R15: 00007ffc8d1635f8
 </TASK>

Allocated by task 27785:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 poison_kmalloc_redzone mm/kasan/common.c:400 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:417
 kasan_kmalloc include/linux/kasan.h:262 [inline]
 __do_kmalloc_node mm/slub.c:5634 [inline]
 __kmalloc_noprof+0x32f/0x880 mm/slub.c:5646
 kmalloc_noprof include/linux/slab.h:961 [inline]
 kmalloc_array_noprof include/linux/slab.h:1003 [inline]
 security_inode_init_security+0x13f/0x390 security/security.c:1868
 shmem_symlink+0x135/0x9f0 mm/shmem.c:4099
 vfs_symlink fs/namei.c:4817 [inline]
 vfs_symlink+0x403/0x680 fs/namei.c:4801
 do_symlinkat+0x261/0x310 fs/namei.c:4843
 __do_sys_symlinkat fs/namei.c:4859 [inline]
 __se_sys_symlinkat fs/namei.c:4856 [inline]
 __x64_sys_symlinkat+0x93/0xc0 fs/namei.c:4856
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 27785:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 __kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:587
 kasan_save_free_info mm/kasan/kasan.h:406 [inline]
 poison_slab_object mm/kasan/common.c:252 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284
 kasan_slab_free include/linux/kasan.h:234 [inline]
 slab_free_hook mm/slub.c:2530 [inline]
 slab_free mm/slub.c:6619 [inline]
 kfree+0x2b8/0x6d0 mm/slub.c:6826
 security_inode_init_security+0x2eb/0x390 security/security.c:1895
 shmem_symlink+0x135/0x9f0 mm/shmem.c:4099
 vfs_symlink fs/namei.c:4817 [inline]
 vfs_symlink+0x403/0x680 fs/namei.c:4801
 do_symlinkat+0x261/0x310 fs/namei.c:4843
 __do_sys_symlinkat fs/namei.c:4859 [inline]
 __se_sys_symlinkat fs/namei.c:4856 [inline]
 __x64_sys_symlinkat+0x93/0xc0 fs/namei.c:4856
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888033cfca00
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 48 bytes inside of
 freed 256-byte region [ffff888033cfca00, ffff888033cfcb00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x33cfc
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
ksm flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88813ff26b40 ffffea0000ca5f80 dead000000000003
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88813ff26b40 ffffea0000ca5f80 dead000000000003
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000001 ffffea0000cf3f01 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 5816, tgid 5816 (syz-executor), ts 64932698491, free_ts 64928315443
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1850
 prep_new_page mm/page_alloc.c:1858 [inline]
 get_page_from_freelist+0x10a3/0x3a30 mm/page_alloc.c:3884
 __alloc_frozen_pages_noprof+0x25f/0x2470 mm/page_alloc.c:5183
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:3046 [inline]
 allocate_slab mm/slub.c:3219 [inline]
 new_slab+0x24a/0x360 mm/slub.c:3273
 ___slab_alloc+0xdc4/0x1ae0 mm/slub.c:4643
 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4762
 __slab_alloc_node mm/slub.c:4838 [inline]
 slab_alloc_node mm/slub.c:5260 [inline]
 __do_kmalloc_node mm/slub.c:5633 [inline]
 __kmalloc_noprof+0x501/0x880 mm/slub.c:5646
 kmalloc_noprof include/linux/slab.h:961 [inline]
 kzalloc_noprof include/linux/slab.h:1094 [inline]
 fib_create_info+0x53f/0x46b0 net/ipv4/fib_semantics.c:1402
 fib_table_insert+0x177/0x1c40 net/ipv4/fib_trie.c:1212
 fib_magic+0x4d4/0x5c0 net/ipv4/fib_frontend.c:1134
 fib_add_ifaddr+0x16d/0x580 net/ipv4/fib_frontend.c:1156
 fib_inetaddr_event+0x147/0x270 net/ipv4/fib_frontend.c:1470
 notifier_call_chain+0xbc/0x410 kernel/notifier.c:85
 blocking_notifier_call_chain kernel/notifier.c:380 [inline]
 blocking_notifier_call_chain+0x69/0xa0 kernel/notifier.c:368
 __inet_insert_ifa+0x925/0xcd0 net/ipv4/devinet.c:566
page last free pid 5816 tgid 5816 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1394 [inline]
 __free_frozen_pages+0x7df/0x1160 mm/page_alloc.c:2906
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:352
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4962 [inline]
 slab_alloc_node mm/slub.c:5272 [inline]
 kmem_cache_alloc_lru_noprof+0x254/0x6e0 mm/slub.c:5291
 sock_alloc_inode+0x25/0x1c0 net/socket.c:322
 alloc_inode+0x64/0x240 fs/inode.c:346
 new_inode_pseudo include/linux/fs.h:3395 [inline]
 sock_alloc+0x40/0x280 net/socket.c:637
 __sock_create+0xc1/0x8d0 net/socket.c:1569
 sock_create net/socket.c:1663 [inline]
 __sys_socket_create net/socket.c:1700 [inline]
 __sys_socket+0x14d/0x260 net/socket.c:1747
 __do_sys_socket net/socket.c:1761 [inline]
 __se_sys_socket net/socket.c:1759 [inline]
 __x64_sys_socket+0x72/0xb0 net/socket.c:1759
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888033cfc900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888033cfc980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888033cfca00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888033cfca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888033cfcb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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