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BUG: KASAN: slab-use-after-free in jfs_readdir+0x10a5/0x33f0
Read of size 8 at addr ffff8881beb8f030 by task syz.0.603/8227

CPU: 0 UID: 0 PID: 8227 Comm: syz.0.603 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_address_description+0x55/0x1e0
 print_report+0x58/0x70
 kasan_report+0x117/0x150
 jfs_readdir+0x10a5/0x33f0
 wrap_directory_iterator+0x96/0xe0
 iterate_dir+0x2e2/0x4d0
 __se_sys_getdents64+0xf1/0x280
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f728099e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f727ebf6028 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007f7280c25fa0 RCX: 00007f728099e0d9
RDX: 000000000000004f RSI: 0000000000000000 RDI: 0000000000000005
RBP: 00007f7280a35024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7280c26038 R14: 00007f7280c25fa0 R15: 00007ffe31fb9f38
 </TASK>

Allocated by task 8227:
 kasan_save_track+0x3e/0x80
 __kasan_slab_alloc+0x6c/0x80
 kmem_cache_alloc_noprof+0x2a0/0x5f0
 mempool_alloc_noprof+0x1bf/0x300
 __get_metapage+0x4ed/0xdf0
 dtSplitRoot+0x216/0x1900
 dtInsert+0xedd/0x5cb0
 jfs_mkdir+0x76b/0xb00
 vfs_mkdir+0x406/0x620
 filename_mkdirat+0x285/0x510
 __se_sys_mkdirat+0x35/0x150
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 8227:
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x40/0x50
 __kasan_slab_free+0x5c/0x80
 kmem_cache_free+0x182/0x650
 mempool_free+0xec/0x130
 release_metapage+0x7f5/0xa60
 jfs_readdir+0xe32/0x33f0
 wrap_directory_iterator+0x96/0xe0
 iterate_dir+0x2e2/0x4d0
 __se_sys_getdents64+0xf1/0x280
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8881beb8f000
 which belongs to the cache jfs_mp of size 184
The buggy address is located 48 bytes inside of
 freed 184-byte region [ffff8881beb8f000, ffff8881beb8f0b8)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1beb8f
flags: 0x57ff00000000000(node=1|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 057ff00000000000 ffff8881686beb40 dead000000000122 0000000000000000
raw: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5735, tgid 5733 (syz.1.6), ts 61784718326
 post_alloc_hook+0x1f9/0x250
 get_page_from_freelist+0x2205/0x2280
 __alloc_frozen_pages_noprof+0x217/0x5a0
 allocate_slab+0x7c/0x5e0
 refill_objects+0x2d5/0x350
 __pcs_replace_empty_main+0x2bf/0x6b0
 kmem_cache_alloc_noprof+0x382/0x5f0
 mempool_alloc_noprof+0x1bf/0x300
 __get_metapage+0x4ed/0xdf0
 diReadSpecial+0x24f/0x710
 jfs_mount+0x73/0x870
 jfs_fill_super+0x69f/0xda0
 get_tree_bdev_flags+0x430/0x4f0
 vfs_get_tree+0x92/0x2a0
 do_new_mount+0x319/0xdc0
 __se_sys_mount+0x31d/0x420
page last free pid 15 tgid 15 ts 58608051039 stack trace:
 __free_frozen_pages+0xc8f/0xd80
 rcu_core+0x78b/0x10a0
 handle_softirqs+0x225/0x840
 run_ksoftirqd+0x36/0x60
 smpboot_thread_fn+0x57c/0xa80
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30

Memory state around the buggy address:
 ffff8881beb8ef00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
 ffff8881beb8ef80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8881beb8f000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff8881beb8f080: fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc fa
 ffff8881beb8f100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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