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BUG: KASAN: slab-use-after-free in jfs_lazycommit+0xa29/0xb20 fs/jfs/jfs_txnmgr.c:2736
Read of size 4 at addr ffff88801f6bfe94 by task jfsCommit/134

CPU: 0 PID: 134 Comm: jfsCommit Not tainted 6.9.0-rc2-syzkaller #0
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 lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 jfs_lazycommit+0xa29/0xb20 fs/jfs/jfs_txnmgr.c:2736
 kthread+0x2c1/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
 </TASK>

Allocated by task 6552:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:387
 kmalloc include/linux/slab.h:628 [inline]
 kzalloc include/linux/slab.h:749 [inline]
 jfs_fill_super+0xe5/0xd20 fs/jfs/super.c:495
 mount_bdev+0x1e3/0x2d0 fs/super.c:1676
 legacy_get_tree+0x109/0x220 fs/fs_context.c:662
 vfs_get_tree+0x8f/0x380 fs/super.c:1797
 do_new_mount fs/namespace.c:3352 [inline]
 path_mount+0x14e6/0x1f20 fs/namespace.c:3679
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount fs/namespace.c:3875 [inline]
 __x64_sys_mount+0x297/0x320 fs/namespace.c:3875
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x72/0x7a

Freed by task 5209:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
 poison_slab_object mm/kasan/common.c:240 [inline]
 __kasan_slab_free+0x11d/0x1a0 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2106 [inline]
 slab_free mm/slub.c:4280 [inline]
 kfree+0x129/0x390 mm/slub.c:4390
 generic_shutdown_super+0x159/0x3d0 fs/super.c:641
 kill_block_super+0x3b/0x90 fs/super.c:1693
 deactivate_locked_super+0xbe/0x1a0 fs/super.c:472
 deactivate_super+0xde/0x100 fs/super.c:505
 cleanup_mnt+0x222/0x450 fs/namespace.c:1267
 task_work_run+0x14e/0x250 kernel/task_work.c:180
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x275/0x2a0 kernel/entry/common.c:218
 do_syscall_64+0xe2/0x260 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x72/0x7a

The buggy address belongs to the object at ffff88801f6bfe00
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 148 bytes inside of
 freed 256-byte region [ffff88801f6bfe00, ffff88801f6bff00)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1f6be
head: order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0xfff80000000840(slab|head|node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffffff()
raw: 00fff80000000840 ffff888015442b40 ffffea0000b3c000 dead000000000005
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
head: 00fff80000000840 ffff888015442b40 ffffea0000b3c000 dead000000000005
head: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
head: 00fff80000000001 ffffea00007daf81 dead000000000122 00000000ffffffff
head: 0000000200000000 0000000000000000 00000000ffffffff 0000000000000000
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 5203, tgid 5203 (syz-executor.2), ts 47844292432, free_ts 47307943551
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317
 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575
 __alloc_pages_node include/linux/gfp.h:238 [inline]
 alloc_pages_node include/linux/gfp.h:261 [inline]
 alloc_slab_page mm/slub.c:2175 [inline]
 allocate_slab mm/slub.c:2338 [inline]
 new_slab+0xcc/0x3a0 mm/slub.c:2391
 ___slab_alloc+0x66d/0x1790 mm/slub.c:3525
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3610
 __slab_alloc_node mm/slub.c:3663 [inline]
 slab_alloc_node mm/slub.c:3835 [inline]
 __do_kmalloc_node mm/slub.c:3965 [inline]
 __kmalloc+0x3b4/0x440 mm/slub.c:3979
 kmalloc include/linux/slab.h:632 [inline]
 kzalloc include/linux/slab.h:749 [inline]
 fib_create_info+0x852/0x4d50 net/ipv4/fib_semantics.c:1459
 fib_table_insert+0x1d7/0x1d70 net/ipv4/fib_trie.c:1237
 fib_magic+0x4d6/0x5c0 net/ipv4/fib_frontend.c:1104
 fib_add_ifaddr+0x393/0x560 net/ipv4/fib_frontend.c:1141
 fib_netdev_event+0x38d/0x710 net/ipv4/fib_frontend.c:1486
 notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1950
 call_netdevice_notifiers_extack net/core/dev.c:1988 [inline]
 call_netdevice_notifiers net/core/dev.c:2002 [inline]
 __dev_notify_flags+0x12d/0x2e0 net/core/dev.c:8725
 dev_change_flags+0x10c/0x160 net/core/dev.c:8763
page last free pid 15 tgid 15 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487
 rcu_do_batch kernel/rcu/tree.c:2196 [inline]
 rcu_core+0x828/0x16b0 kernel/rcu/tree.c:2471
 __do_softirq+0x218/0x922 kernel/softirq.c:554

Memory state around the buggy address:
 ffff88801f6bfd80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88801f6bfe00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88801f6bfe80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff88801f6bff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88801f6bff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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