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BUG: KASAN: slab-use-after-free in jfs_lazycommit+0x749/0xaa0
Read of size 4 at addr ffff8881bc528094 by task jfsCommit/116

CPU: 0 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+0xe8/0x150
 print_report+0xba/0x230
 kasan_report+0x117/0x150
 jfs_lazycommit+0x749/0xaa0
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Allocated by task 10448:
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_cache_noprof+0x31c/0x660
 jfs_fill_super+0xc2/0xd80
 get_tree_bdev_flags+0x431/0x4f0
 vfs_get_tree+0x92/0x2a0
 do_new_mount+0x341/0xd30
 __se_sys_mount+0x31d/0x420
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 10204:
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x5c/0x80
 kfree+0x1c1/0x630
 generic_shutdown_super+0x13d/0x2d0
 kill_block_super+0x44/0x90
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x437/0x4d0
 task_work_run+0x1d9/0x270
 exit_to_user_mode_loop+0xed/0x480
 do_syscall_64+0x32d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8881bc528000
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 148 bytes inside of
 freed 256-byte region [ffff8881bc528000, ffff8881bc528100)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8881bc528600 pfn:0x1bc528
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x57ff00000000240(workingset|head|node=1|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 057ff00000000240 ffff888100041b40 ffffea0005ab3690 ffffea0005d40d90
raw: ffff8881bc528600 0000000800100009 00000000f5000000 0000000000000000
head: 057ff00000000240 ffff888100041b40 ffffea0005ab3690 ffffea0005d40d90
head: ffff8881bc528600 0000000800100009 00000000f5000000 0000000000000000
head: 057ff00000000001 ffffea0006f14a01 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 5819, tgid 5819 (syz-executor), ts 66956601190, free_ts 66952501092
 post_alloc_hook+0x231/0x280
 get_page_from_freelist+0x24dc/0x2580
 __alloc_frozen_pages_noprof+0x18d/0x380
 allocate_slab+0x77/0x660
 refill_objects+0x331/0x3c0
 __pcs_replace_empty_main+0x2e6/0x730
 __kmalloc_cache_noprof+0x392/0x660
 ____ip_mc_inc_group+0x518/0xdd0
 ip_mc_up+0x115/0x2e0
 inetdev_event+0xff6/0x1610
 notifier_call_chain+0x1be/0x400
 __dev_notify_flags+0x1a9/0x310
 netif_change_flags+0xe8/0x1a0
 do_setlink+0xf82/0x4590
 rtnl_newlink+0x15a9/0x1be0
 rtnetlink_rcv_msg+0x7d5/0xbe0
page last free pid 5811 tgid 5811 stack trace:
 __free_frozen_pages+0xc2b/0xdb0
 rcu_core+0x7cd/0x1070
 handle_softirqs+0x22a/0x870
 do_softirq+0x76/0xd0
 __local_bh_enable_ip+0xf8/0x130
 ip6_route_add+0xe8/0x1b0
 addrconf_prefix_route+0x3a2/0x480
 inet6_addr_add+0x508/0xb20
 inet6_rtm_newaddr+0xa17/0xe30
 rtnetlink_rcv_msg+0x7d5/0xbe0
 netlink_rcv_skb+0x232/0x4b0
 netlink_unicast+0x80f/0x9b0
 netlink_sendmsg+0x813/0xb40
 __sys_sendto+0x672/0x710
 __x64_sys_sendto+0xde/0x100
 do_syscall_64+0x14d/0xf80

Memory state around the buggy address:
 ffff8881bc527f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881bc528000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8881bc528080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff8881bc528100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8881bc528180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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