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BUG: KASAN: slab-out-of-bounds in __lock_acquire+0x78/0x1fd0 kernel/locking/lockdep.c:5005
Read of size 8 at addr ffff88801fff1fa8 by task kworker/u8:1/12

CPU: 0 PID: 12 Comm: kworker/u8:1 Not tainted 6.9.0-rc2-next-20240405-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Workqueue: writeback wb_workfn (flush-7:2)
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_do_writeback fs/fs-writeback.c:2274 [inline]
 wb_workfn+0x410/0x1090 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 9461:
 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:4078 [inline]
 __kmalloc_noprof+0x200/0x400 mm/slub.c:4091
 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_path_perm+0x2b7/0x740 security/tomoyo/file.c:822
 tomoyo_path_unlink+0xd0/0x110 security/tomoyo/tomoyo.c:162
 security_path_unlink+0xe1/0x140 security/security.c:1857
 do_unlinkat+0x3e6/0x830 fs/namei.c:4396
 __do_sys_unlink fs/namei.c:4447 [inline]
 __se_sys_unlink fs/namei.c:4445 [inline]
 __x64_sys_unlink+0x49/0x60 fs/namei.c:4445
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x72/0x7a

Freed by task 9461:
 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:2190 [inline]
 slab_free mm/slub.c:4393 [inline]
 kfree+0x149/0x350 mm/slub.c:4514
 tomoyo_realpath_from_path+0x5a9/0x5e0 security/tomoyo/realpath.c:286
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x2b7/0x740 security/tomoyo/file.c:822
 tomoyo_path_unlink+0xd0/0x110 security/tomoyo/tomoyo.c:162
 security_path_unlink+0xe1/0x140 security/security.c:1857
 do_unlinkat+0x3e6/0x830 fs/namei.c:4396
 __do_sys_unlink fs/namei.c:4447 [inline]
 __se_sys_unlink fs/namei.c:4445 [inline]
 __x64_sys_unlink+0x49/0x60 fs/namei.c:4445
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x72/0x7a

The buggy address belongs to the object at ffff88801fff0000
 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 [ffff88801fff0000, ffff88801fff1000)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1fff0
head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff80000000040(head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffefff(slab)
raw: 00fff80000000040 ffff888015042140 ffffea00007eb200 dead000000000002
raw: 0000000000000000 0000000000040004 00000001ffffefff 0000000000000000
head: 00fff80000000040 ffff888015042140 ffffea00007eb200 dead000000000002
head: 0000000000000000 0000000000040004 00000001ffffefff 0000000000000000
head: 00fff80000000003 ffffea00007ffc01 ffffea00007ffc48 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 -1195868630 (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:2259
 allocate_slab+0x5a/0x2e0 mm/slub.c:2422
 new_slab mm/slub.c:2475 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3624
 __slab_alloc+0x58/0xa0 mm/slub.c:3714
 __slab_alloc_node mm/slub.c:3767 [inline]
 slab_alloc_node mm/slub.c:3945 [inline]
 kmalloc_trace_noprof+0x1d5/0x2b0 mm/slub.c:4104
 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
 disk_uevent+0x2b3/0x490 block/genhd.c:335
 device_add_disk+0xc21/0xf20 block/genhd.c:519
 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
 do_one_initcall+0x248/0x880 init/main.c:1258
 do_initcall_level+0x157/0x210 init/main.c:1320
 do_initcalls+0x3f/0x80 init/main.c:1336
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88801fff1e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88801fff1f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88801fff1f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                  ^
 ffff88801fff2000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88801fff2080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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