==================================================================
BUG: KASAN: slab-out-of-bounds in __lock_acquire+0x78/0x1fd0 kernel/locking/lockdep.c:5005
Read of size 8 at addr ffff88801ffcbfa8 by task kworker/u8:7/1274

CPU: 1 PID: 1274 Comm: kworker/u8:7 Not tainted 6.9.0-rc2-next-20240402-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Workqueue: writeback wb_workfn (flush-7:4)
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 __lock_acquire+0x78/0x1fd0 kernel/locking/lockdep.c:5005
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 wb_writeback+0x66f/0xd30 fs/fs-writeback.c:2160
 wb_check_old_data_flush fs/fs-writeback.c:2233 [inline]
 wb_do_writeback fs/fs-writeback.c:2286 [inline]
 wb_workfn+0xba1/0x1090 fs/fs-writeback.c:2314
 process_one_work kernel/workqueue.c:3218 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3299
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3380
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
 </TASK>

Allocated by task 4535:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slub.c:4048 [inline]
 __kmalloc_noprof+0x200/0x410 mm/slub.c:4061
 kmalloc_noprof include/linux/slab.h:664 [inline]
 tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_check_open_permission+0x255/0x500 security/tomoyo/file.c:771
 security_file_open+0x69/0x570 security/security.c:2961
 do_dentry_open+0x327/0x15a0 fs/open.c:942
 do_open fs/namei.c:3642 [inline]
 path_openat+0x2860/0x3240 fs/namei.c:3799
 do_filp_open+0x235/0x490 fs/namei.c:3826
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1406
 do_sys_open fs/open.c:1421 [inline]
 __do_sys_openat fs/open.c:1437 [inline]
 __se_sys_openat fs/open.c:1432 [inline]
 __x64_sys_openat+0x247/0x2a0 fs/open.c:1432
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x72/0x7a

Freed by task 4535:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240
 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2180 [inline]
 slab_free mm/slub.c:4363 [inline]
 kfree+0x149/0x350 mm/slub.c:4484
 tomoyo_realpath_from_path+0x5a9/0x5e0 security/tomoyo/realpath.c:286
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_check_open_permission+0x255/0x500 security/tomoyo/file.c:771
 security_file_open+0x69/0x570 security/security.c:2961
 do_dentry_open+0x327/0x15a0 fs/open.c:942
 do_open fs/namei.c:3642 [inline]
 path_openat+0x2860/0x3240 fs/namei.c:3799
 do_filp_open+0x235/0x490 fs/namei.c:3826
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1406
 do_sys_open fs/open.c:1421 [inline]
 __do_sys_openat fs/open.c:1437 [inline]
 __se_sys_openat fs/open.c:1432 [inline]
 __x64_sys_openat+0x247/0x2a0 fs/open.c:1432
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x72/0x7a

The buggy address belongs to the object at ffff88801ffca000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 4008 bytes to the right of
 allocated 4096-byte region [ffff88801ffca000, ffff88801ffcb000)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1ffc8
head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0xfff80000000040(head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffefff(slab)
raw: 00fff80000000040 ffff888015042140 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000040004 00000001ffffefff 0000000000000000
head: 00fff80000000040 ffff888015042140 0000000000000000 dead000000000001
head: 0000000000000000 0000000000040004 00000001ffffefff 0000000000000000
head: 00fff80000000003 ffffea00007ff201 ffffea00007ff248 00000000ffffffff
head: 0000000800000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid -489484029 (swapper/0), ts 1, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1490
 prep_new_page mm/page_alloc.c:1498 [inline]
 get_page_from_freelist+0x2e7e/0x2f40 mm/page_alloc.c:3454
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4712
 __alloc_pages_node_noprof include/linux/gfp.h:244 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:271 [inline]
 alloc_slab_page+0x5f/0x120 mm/slub.c:2249
 allocate_slab+0x5a/0x2e0 mm/slub.c:2412
 new_slab mm/slub.c:2465 [inline]
 ___slab_alloc+0xea8/0x1430 mm/slub.c:3599
 __slab_alloc+0x58/0xa0 mm/slub.c:3684
 __slab_alloc_node mm/slub.c:3737 [inline]
 slab_alloc_node mm/slub.c:3915 [inline]
 kmalloc_trace_noprof+0x1d5/0x2b0 mm/slub.c:4074
 kmalloc_noprof include/linux/slab.h:660 [inline]
 kzalloc_noprof include/linux/slab.h:775 [inline]
 kobject_uevent_env+0x28b/0x8e0 lib/kobject_uevent.c:525
 device_add+0x63b/0xbf0 drivers/base/core.c:3693
 device_create_groups_vargs drivers/base/core.c:4404 [inline]
 device_create+0x257/0x2e0 drivers/base/core.c:4443
 bdi_register_va+0x8b/0x730 mm/backing-dev.c:967
 bdi_register+0xd5/0x120 mm/backing-dev.c:999
 device_add_disk+0x6d9/0xf20 block/genhd.c:495
 add_disk include/linux/blkdev.h:716 [inline]
 loop_add+0x8c1/0xba0 drivers/block/loop.c:2083
 loop_init+0x17a/0x230 drivers/block/loop.c:2275
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88801ffcbe80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88801ffcbf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88801ffcbf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                  ^
 ffff88801ffcc000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88801ffcc080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================