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BUG: KASAN: use-after-free in memcpy include/linux/fortify-string.h:191 [inline]
BUG: KASAN: use-after-free in __d_alloc+0x161/0x950 fs/dcache.c:1775
Read of size 5 at addr ffff888011f44420 by task kdevtmpfs/22

CPU: 0 PID: 22 Comm: kdevtmpfs Not tainted 5.14.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x57/0x7d lib/dump_stack.c:105
 print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:233
 __kasan_report mm/kasan/report.c:419 [inline]
 kasan_report.cold+0x83/0xdf mm/kasan/report.c:436
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189
 memcpy+0x20/0x60 mm/kasan/shadow.c:65
 memcpy include/linux/fortify-string.h:191 [inline]
 __d_alloc+0x161/0x950 fs/dcache.c:1775
 d_alloc+0x3f/0x200 fs/dcache.c:1823
 __lookup_hash+0x97/0x140 fs/namei.c:1554
 kern_path_locked+0x146/0x300 fs/namei.c:2567
 handle_remove+0x9a/0x4fa drivers/base/devtmpfs.c:312
 handle drivers/base/devtmpfs.c:382 [inline]
 devtmpfs_work_loop drivers/base/devtmpfs.c:395 [inline]
 devtmpfsd+0x176/0x24e drivers/base/devtmpfs.c:437
 kthread+0x38b/0x460 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Allocated by task 22:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x83/0xb0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook mm/slab.h:519 [inline]
 slab_alloc_node mm/slub.c:2959 [inline]
 slab_alloc mm/slub.c:2967 [inline]
 kmem_cache_alloc+0x285/0x4a0 mm/slub.c:2972
 getname_kernel+0x48/0x330 fs/namei.c:226
 kern_path_locked+0x6f/0x300 fs/namei.c:2558
 handle_remove+0x9a/0x4fa drivers/base/devtmpfs.c:312
 handle drivers/base/devtmpfs.c:382 [inline]
 devtmpfs_work_loop drivers/base/devtmpfs.c:395 [inline]
 devtmpfsd+0x176/0x24e drivers/base/devtmpfs.c:437
 kthread+0x38b/0x460 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Freed by task 22:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:360
 ____kasan_slab_free mm/kasan/common.c:366 [inline]
 ____kasan_slab_free mm/kasan/common.c:328 [inline]
 __kasan_slab_free+0xff/0x130 mm/kasan/common.c:374
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1628 [inline]
 slab_free_freelist_hook+0xe3/0x250 mm/slub.c:1653
 slab_free mm/slub.c:3213 [inline]
 kmem_cache_free+0x8a/0x5b0 mm/slub.c:3229
 putname include/linux/err.h:41 [inline]
 filename_parentat fs/namei.c:2547 [inline]
 kern_path_locked+0xa7/0x300 fs/namei.c:2558
 handle_remove+0x9a/0x4fa drivers/base/devtmpfs.c:312
 handle drivers/base/devtmpfs.c:382 [inline]
 devtmpfs_work_loop drivers/base/devtmpfs.c:395 [inline]
 devtmpfsd+0x176/0x24e drivers/base/devtmpfs.c:437
 kthread+0x38b/0x460 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

The buggy address belongs to the object at ffff888011f44400
 which belongs to the cache names_cache of size 4096
The buggy address is located 32 bytes inside of
 4096-byte region [ffff888011f44400, ffff888011f45400)
The buggy address belongs to the page:
page:ffffea000047d000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11f40
head:ffffea000047d000 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 0000000100000001 ffff88800fdc43c0
raw: 0000000000000000 0000000080070007 00000001ffffffff 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 6375, ts 24250878650, free_ts 23733110061
 prep_new_page mm/page_alloc.c:2436 [inline]
 get_page_from_freelist+0xa6f/0x2f50 mm/page_alloc.c:4168
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5390
 alloc_slab_page mm/slub.c:1691 [inline]
 allocate_slab+0x32e/0x4b0 mm/slub.c:1831
 new_slab mm/slub.c:1894 [inline]
 new_slab_objects mm/slub.c:2640 [inline]
 ___slab_alloc+0x4ba/0x820 mm/slub.c:2803
 __slab_alloc.constprop.0+0xa7/0xf0 mm/slub.c:2843
 slab_alloc_node mm/slub.c:2925 [inline]
 slab_alloc mm/slub.c:2967 [inline]
 kmem_cache_alloc+0x3e1/0x4a0 mm/slub.c:2972
 getname_flags.part.0+0x4a/0x440 fs/namei.c:138
 do_sys_openat2+0xd2/0x400 fs/open.c:1194
 do_sys_open fs/open.c:1216 [inline]
 __do_sys_open fs/open.c:1224 [inline]
 __se_sys_open fs/open.c:1220 [inline]
 __x64_sys_open+0xfd/0x1a0 fs/open.c:1220
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1346 [inline]
 free_pcp_prepare+0x2c5/0x780 mm/page_alloc.c:1397
 free_unref_page_prepare mm/page_alloc.c:3332 [inline]
 free_unref_page+0x19/0x690 mm/page_alloc.c:3411
 unfreeze_partials+0x17c/0x1d0 mm/slub.c:2421
 put_cpu_partial+0x13d/0x230 mm/slub.c:2457
 qlink_free mm/kasan/quarantine.c:146 [inline]
 qlist_free_all+0x5a/0xc0 mm/kasan/quarantine.c:165
 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272
 __kasan_slab_alloc+0x95/0xb0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook mm/slab.h:519 [inline]
 slab_alloc_node mm/slub.c:2959 [inline]
 slab_alloc mm/slub.c:2967 [inline]
 kmem_cache_alloc+0x285/0x4a0 mm/slub.c:2972
 ptlock_alloc+0x19/0x60 mm/memory.c:5458
 ptlock_init include/linux/mm.h:2223 [inline]
 pgtable_pte_page_ctor include/linux/mm.h:2250 [inline]
 __pte_alloc_one include/asm-generic/pgalloc.h:66 [inline]
 pte_alloc_one+0x4c/0x190 arch/x86/mm/pgtable.c:33
 __pte_alloc+0x15/0x240 mm/memory.c:439
 copy_pte_range mm/memory.c:1021 [inline]
 copy_pmd_range mm/memory.c:1156 [inline]
 copy_pud_range mm/memory.c:1193 [inline]
 copy_p4d_range mm/memory.c:1217 [inline]
 copy_page_range+0x1009/0x32b0 mm/memory.c:1290
 dup_mmap kernel/fork.c:599 [inline]
 dup_mm+0x7cc/0x1090 kernel/fork.c:1381
 copy_mm kernel/fork.c:1433 [inline]
 copy_process+0x5c89/0x69f0 kernel/fork.c:2121
 kernel_clone+0xb8/0x7f0 kernel/fork.c:2511
 __do_sys_clone+0xaf/0xf0 kernel/fork.c:2628

Memory state around the buggy address:
 ffff888011f44300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888011f44380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888011f44400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                               ^
 ffff888011f44480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888011f44500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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