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BUG: KASAN: slab-use-after-free in jfs_lazycommit+0x74b/0xa90
Read of size 4 at addr ffff888021ce8094 by task jfsCommit/116

CPU: 1 UID: 0 PID: 116 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+0x439/0x7d0
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Allocated by task 8520:
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_cache_noprof+0x230/0x3d0
 jfs_fill_super+0xc2/0xd80
 get_tree_bdev_flags+0x40e/0x4d0
 vfs_get_tree+0x92/0x2b0
 do_new_mount+0x2a2/0xa30
 __se_sys_mount+0x317/0x410
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 8376:
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x5b/0x80
 kfree+0x18e/0x440
 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+0xec/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888021ce8000
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 148 bytes inside of
 freed 256-byte region [ffff888021ce8000, ffff888021ce8100)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888021ce8c00 pfn:0x21ce8
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801a041b40 ffffea00043eb580 dead000000000006
raw: ffff888021ce8c00 000000000010000f 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801a041b40 ffffea00043eb580 dead000000000006
head: ffff888021ce8c00 000000000010000f 00000000f5000000 0000000000000000
head: 00fff00000000001 ffffea0000873a01 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 5833, tgid 5833 (syz-executor), ts 65419191650, free_ts 61864561103
 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/0x1420
 __kmalloc_noprof+0x305/0x4f0
 __register_sysctl_table+0xba1/0x1340
 mpls_dev_sysctl_register+0x188/0x270
 mpls_dev_notify+0x357/0x7a0
 notifier_call_chain+0x1b6/0x3e0
 register_netdevice+0x1608/0x1ae0
 veth_newlink+0x42f/0xa50
 rtnl_newlink_create+0x310/0xb00
 rtnl_newlink+0x16d6/0x1c70
 rtnetlink_rcv_msg+0x7cf/0xb70
page last free pid 0 tgid 0 stack trace:
 __free_frozen_pages+0xbc4/0xd30
 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

Memory state around the buggy address:
 ffff888021ce7f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888021ce8000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888021ce8080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff888021ce8100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888021ce8180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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