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BUG: KASAN: slab-use-after-free in jfs_lazycommit+0x74b/0xa90
Read of size 4 at addr ffff888107356a94 by task jfsCommit/117

CPU: 0 UID: 0 PID: 117 Comm: jfsCommit 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
 jfs_lazycommit+0x74b/0xa90
 kthread+0x711/0x8a0
 ret_from_fork+0x4bc/0x870
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Allocated by task 15542:
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_cache_noprof+0x3d5/0x6f0
 jfs_fill_super+0xc2/0xd80
 get_tree_bdev_flags+0x40e/0x4d0
 vfs_get_tree+0x92/0x2b0
 do_new_mount+0x302/0x9e0
 __se_sys_mount+0x313/0x410
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 13465:
 kasan_save_track+0x3e/0x80
 __kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x5c/0x80
 kfree+0x19a/0x6d0
 generic_shutdown_super+0x135/0x2c0
 kill_block_super+0x44/0x90
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x425/0x4c0
 task_work_run+0x1d4/0x260
 exit_to_user_mode_loop+0xe9/0x130
 do_syscall_64+0x2bd/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888107356a00
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 148 bytes inside of
 freed 256-byte region [ffff888107356a00, ffff888107356b00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x107356
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x57ff00000000040(head|node=1|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 057ff00000000040 ffff88801ac41b40 ffffea000441c100 dead000000000002
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 057ff00000000040 ffff88801ac41b40 ffffea000441c100 dead000000000002
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 057ff00000000001 ffffea00041cd581 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5842, tgid 5842 (syz-executor), ts 58955805250, free_ts 58833639936
 post_alloc_hook+0x240/0x2a0
 get_page_from_freelist+0x2365/0x2440
 __alloc_frozen_pages_noprof+0x181/0x370
 alloc_pages_mpol+0x232/0x4a0
 allocate_slab+0x96/0x3a0
 ___slab_alloc+0xe94/0x1920
 __slab_alloc+0x65/0x100
 __kmalloc_noprof+0x471/0x7f0
 udp_tunnel_nic_netdevice_event+0x4c3/0x1820
 notifier_call_chain+0x1b6/0x3e0
 register_netdevice+0x1608/0x1ae0
 nsim_create+0xae8/0xf10
 __nsim_dev_port_add+0x6b6/0xb10
 nsim_dev_port_add_all+0x37/0xf0
 nsim_drv_probe+0x88e/0xba0
 really_probe+0x26d/0x9e0
page last free pid 5842 tgid 5842 stack trace:
 __free_frozen_pages+0xbc4/0xd30
 __put_partials+0x146/0x170
 put_cpu_partial+0x1f2/0x2e0
 __slab_free+0x2b9/0x390
 qlist_free_all+0x97/0x140
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 __kmalloc_cache_noprof+0x36f/0x6f0
 __ipv6_dev_mc_inc+0x44f/0xa50
 ipv6_add_dev+0xe72/0x1380
 addrconf_notify+0x794/0x1010
 notifier_call_chain+0x1b6/0x3e0
 register_netdevice+0x1608/0x1ae0
 geneve_configure+0x611/0xa30
 geneve_newlink+0x1a1/0x240
 rtnl_newlink_create+0x310/0xb00

Memory state around the buggy address:
 ffff888107356980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888107356a00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888107356a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff888107356b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888107356b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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