loop4: detected capacity change from 0 to 32768
==================================================================
BUG: KASAN: slab-use-after-free in dtReadFirst+0x502/0x930
Read of size 4 at addr ffff88802c6480d0 by task syz.4.419/9439

CPU: 0 UID: 0 PID: 9439 Comm: syz.4.419 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+0x189/0x250
 print_report+0xca/0x240
 kasan_report+0x118/0x150
 dtReadFirst+0x502/0x930
 jfs_readdir+0x709/0x3ae0
 wrap_directory_iterator+0x96/0xe0
 iterate_dir+0x399/0x570
 __se_sys_getdents64+0xe4/0x260
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4dd318ebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4dd40dc038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007f4dd33c5fa0 RCX: 00007f4dd318ebe9
RDX: 0000000000001000 RSI: 0000200000000f80 RDI: 0000000000000005
RBP: 00007f4dd3211e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4dd33c6038 R14: 00007f4dd33c5fa0 R15: 00007ffc25ba7b88
 </TASK>

Allocated by task 6105:
 kasan_save_track+0x3e/0x80
 __kasan_slab_alloc+0x6c/0x80
 kmem_cache_alloc_lru_noprof+0x1c6/0x3d0
 fat_alloc_inode+0x2c/0xd0
 alloc_inode+0x6a/0x1b0
 new_inode+0x22/0x170
 fat_build_inode+0x202/0x3d0
 vfat_create+0x16a/0x250
 path_openat+0x14f4/0x3830
 do_filp_open+0x1fa/0x410
 do_sys_openat2+0x121/0x1c0
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5849:
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x5b/0x80
 kmem_cache_free+0x18f/0x400
 rcu_core+0xcab/0x1770
 handle_softirqs+0x286/0x870
 __irq_exit_rcu+0xca/0x1f0
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 asm_sysvec_apic_timer_interrupt+0x1a/0x20

Last potentially related work creation:
 kasan_save_stack+0x3e/0x60
 kasan_record_aux_stack+0xbd/0xd0
 call_rcu+0x157/0x9c0
 evict+0x847/0x9c0
 evict_inodes+0x64c/0x6d0
 generic_shutdown_super+0x9a/0x2c0
 kill_block_super+0x44/0x90
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x425/0x4c0
 task_work_run+0x1d4/0x260
 exit_to_user_mode_loop+0xec/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88802c648000
 which belongs to the cache fat_inode_cache of size 1480
The buggy address is located 208 bytes inside of
 freed 1480-byte region [ffff88802c648000, ffff88802c6485c8)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802c648648 pfn:0x2c648
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88801f62d601
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801da84780 dead000000000122 0000000000000000
raw: ffff88802c648648 000000008014000e 00000000f5000000 ffff88801f62d601
head: 00fff00000000040 ffff88801da84780 dead000000000122 0000000000000000
head: ffff88802c648648 000000008014000e 00000000f5000000 ffff88801f62d601
head: 00fff00000000003 ffffea0000b19201 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 6105, tgid 6104 (syz.2.34), ts 85198348861, free_ts 77012193310
 post_alloc_hook+0x240/0x2a0
 get_page_from_freelist+0x21e4/0x22c0
 __alloc_frozen_pages_noprof+0x181/0x370
 alloc_pages_mpol+0x232/0x4a0
 allocate_slab+0x8a/0x370
 ___slab_alloc+0xbeb/0x1410
 kmem_cache_alloc_lru_noprof+0x288/0x3d0
 fat_alloc_inode+0x2c/0xd0
 alloc_inode+0x6a/0x1b0
 new_inode+0x22/0x170
 fat_build_inode+0x202/0x3d0
 vfat_create+0x16a/0x250
 path_openat+0x14f4/0x3830
 do_filp_open+0x1fa/0x410
 do_sys_openat2+0x121/0x1c0
 __x64_sys_openat+0x138/0x170
page last free pid 5296 tgid 5296 stack trace:
 __free_frozen_pages+0xbc4/0xd30
 __put_partials+0x156/0x1a0
 put_cpu_partial+0x17c/0x250
 __slab_free+0x2d5/0x3c0
 qlist_free_all+0x97/0x140
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 kmem_cache_alloc_noprof+0x1c1/0x3c0
 getname_flags+0xb8/0x540
 __x64_sys_unlink+0x3a/0x50
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88802c647f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88802c648000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88802c648080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff88802c648100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802c648180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
