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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 ffff88807dc3a630 by task syz.4.3093/17860

CPU: 1 UID: 0 PID: 17860 Comm: syz.4.3093 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: 0033:0x7fa59b38eec9
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:00007fa599191038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa59b5e6270 RCX: 00007fa59b38eec9
RDX: 0000000000000000 RSI: 0000000040946400 RDI: 000000000000000a
RBP: 00007fa59b411f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa59b5e6308 R14: 00007fa59b5e6270 R15: 00007ffe9031ec28
 </TASK>

Allocated by task 7090:
 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
 kmalloc_noprof include/linux/slab.h:957 [inline]
 kzalloc_noprof include/linux/slab.h:1094 [inline]
 bus_add_driver+0x92/0x690 drivers/base/bus.c:662
 driver_register+0x15c/0x4b0 drivers/base/driver.c:249
 c6xdigio_attach drivers/comedi/drivers/c6xdigio.c:253 [inline]
 c6xdigio_attach+0xa3/0x4b0 drivers/comedi/drivers/c6xdigio.c:238
 comedi_device_attach+0x3b3/0x900 drivers/comedi/drivers.c:1007
 do_devconfig_ioctl+0x1b1/0x710 drivers/comedi/comedi_fops.c:872
 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

Freed by task 17641:
 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:2523 [inline]
 slab_free mm/slub.c:6611 [inline]
 kfree+0x2b8/0x6d0 mm/slub.c:6818
 kobject_cleanup lib/kobject.c:689 [inline]
 kobject_release lib/kobject.c:720 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x1e7/0x5a0 lib/kobject.c:737
 bus_remove_driver+0x16e/0x2c0 drivers/base/bus.c:749
 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

The buggy address belongs to the object at ffff88807dc3a600
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 48 bytes inside of
 freed 256-byte region [ffff88807dc3a600, ffff88807dc3a700)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807dc3a600 pfn:0x7dc3a
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 ffff88813ff26b40 ffffea0001f73810 ffffea0000d35910
raw: ffff88807dc3a600 000000000010000f 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88813ff26b40 ffffea0001f73810 ffffea0000d35910
head: ffff88807dc3a600 000000000010000f 00000000f5000000 0000000000000000
head: 00fff00000000001 ffffea0001f70e81 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 5808, tgid 5808 (syz-executor), ts 65188103385, free_ts 65156907180
 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:3039 [inline]
 allocate_slab mm/slub.c:3212 [inline]
 new_slab+0x24a/0x360 mm/slub.c:3266
 ___slab_alloc+0xdc4/0x1ae0 mm/slub.c:4636
 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4755
 __slab_alloc_node mm/slub.c:4831 [inline]
 slab_alloc_node mm/slub.c:5253 [inline]
 __kmalloc_cache_noprof+0x477/0x780 mm/slub.c:5743
 kmalloc_noprof include/linux/slab.h:957 [inline]
 inode_doinit_use_xattr+0x54/0x410 security/selinux/hooks.c:1370
 inode_doinit_with_dentry+0x10c8/0x12e0 security/selinux/hooks.c:1564
 selinux_d_instantiate+0x26/0x30 security/selinux/hooks.c:6523
 security_d_instantiate+0x142/0x1a0 security/security.c:4148
 d_splice_alias_ops+0x92/0x840 fs/dcache.c:2999
 kernfs_iop_lookup+0x23f/0x2d0 fs/kernfs/dir.c:1251
 lookup_open.isra.0+0x4da/0x1580 fs/namei.c:3774
 open_last_lookups fs/namei.c:3895 [inline]
 path_openat+0x893/0x2cb0 fs/namei.c:4131
page last free pid 5808 tgid 5808 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:4955 [inline]
 slab_alloc_node mm/slub.c:5265 [inline]
 kmem_cache_alloc_noprof+0x250/0x6e0 mm/slub.c:5272
 getname_kernel+0x52/0x370 fs/namei.c:249
 kern_path+0x1d/0x50 fs/namei.c:2862
 tomoyo_mount_acl+0x624/0x850 security/tomoyo/mount.c:136
 tomoyo_mount_permission+0x16d/0x420 security/tomoyo/mount.c:237
 security_sb_mount+0x9b/0x260 security/security.c:1609
 path_mount+0x158/0x23a0 fs/namespace.c:3979
 do_mount fs/namespace.c:4050 [inline]
 __do_sys_mount fs/namespace.c:4238 [inline]
 __se_sys_mount fs/namespace.c:4215 [inline]
 __x64_sys_mount+0x293/0x310 fs/namespace.c:4215
 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:
 ffff88807dc3a500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807dc3a580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88807dc3a600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff88807dc3a680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807dc3a700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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