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BUG: KASAN: slab-out-of-bounds in dtSplitPage+0x1248/0x37c0
Read of size 1 at addr ffff8881b7f408b5 by task syz.9.1212/15159

CPU: 1 UID: 0 PID: 15159 Comm: syz.9.1212 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 print_report+0xba/0x230
 kasan_report+0x117/0x150
 dtSplitPage+0x1248/0x37c0
 dtInsert+0x107a/0x5de0
 jfs_mkdir+0x783/0xb00
 vfs_mkdir+0x511/0x5b0
 do_mkdirat+0x27d/0x4b0
 __x64_sys_mkdirat+0x87/0xa0
 do_syscall_64+0xe2/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9af1199b97
Code: 00 66 90 48 89 f2 b9 00 01 00 00 48 89 fe bf 9c ff ff ff e9 db f7 ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 b8 02 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9af2088e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f9af2088ee0 RCX: 00007f9af1199b97
RDX: 00000000000001ff RSI: 0000200000002080 RDI: 00000000ffffff9c
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000002080
R13: 00007f9af2088ea0 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Allocated by task 15159:
 kasan_save_track+0x3e/0x80
 __kasan_slab_alloc+0x6c/0x80
 kmem_cache_alloc_lru_noprof+0x35f/0x6c0
 jfs_alloc_inode+0x28/0x70
 alloc_inode+0x6a/0x1b0
 iget_locked+0x131/0x6a0
 jfs_iget+0x24/0x470
 jfs_lookup+0x220/0x420
 __lookup_slow+0x2b7/0x410
 lookup_slow+0x53/0x70
 path_lookupat+0x3f5/0x8c0
 filename_lookup+0x256/0x5d0
 vfs_statx+0x115/0x570
 __x64_sys_newlstat+0x125/0x1e0
 do_syscall_64+0xe2/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8881b7f40000
 which belongs to the cache jfs_ip of size 2216
The buggy address is located 13 bytes to the right of
 allocated 2216-byte region [ffff8881b7f40000, ffff8881b7f408a8)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1b7f40
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff8881ac5c4401
flags: 0x57ff00000000040(head|node=1|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 057ff00000000040 ffff8881056de280 dead000000000122 0000000000000000
raw: 0000000000000000 00000000800d000d 00000000f5000000 ffff8881ac5c4401
head: 057ff00000000040 ffff8881056de280 dead000000000122 0000000000000000
head: 0000000000000000 00000000800d000d 00000000f5000000 ffff8881ac5c4401
head: 057ff00000000003 ffffea0006dfd001 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Reclaimable, gfp_mask 0xd2050(__GFP_RECLAIMABLE|__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 15159, tgid 15158 (syz.9.1212), ts 421213298628, free_ts 399681856073
 post_alloc_hook+0x228/0x280
 get_page_from_freelist+0x24dc/0x2580
 __alloc_frozen_pages_noprof+0x18d/0x380
 alloc_pages_mpol+0x232/0x4a0
 allocate_slab+0x86/0x3a0
 ___slab_alloc+0xd82/0x1760
 __slab_alloc+0x65/0x100
 kmem_cache_alloc_lru_noprof+0x3ed/0x6c0
 jfs_alloc_inode+0x28/0x70
 alloc_inode+0x6a/0x1b0
 iget_locked+0x131/0x6a0
 jfs_iget+0x24/0x470
 jfs_lookup+0x220/0x420
 __lookup_slow+0x2b7/0x410
 lookup_slow+0x53/0x70
 path_lookupat+0x3f5/0x8c0
page last free pid 14597 tgid 14597 stack trace:
 __free_frozen_pages+0xbb0/0xd10
 __slab_free+0x2ce/0x320
 qlist_free_all+0x97/0x100
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 kmem_cache_alloc_noprof+0x370/0x6e0
 getname_flags+0xb7/0x540
 do_sys_openat2+0xca/0x220
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0xe2/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff8881b7f40780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881b7f40800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8881b7f40880: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
                                     ^
 ffff8881b7f40900: fc fc fc fc fc 00 00 00 00 00 00 00 00 00 00 00
 ffff8881b7f40980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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