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BUG: KASAN: slab-use-after-free in jfs_lazycommit+0x7e0/0xb80 fs/jfs/jfs_txnmgr.c:2736
Read of size 4 at addr ffff888038ac2894 by task jfsCommit/101

CPU: 0 UID: 0 PID: 101 Comm: jfsCommit Not tainted 6.12.0-rc5-syzkaller-00005-ge42b1a9a2557 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 jfs_lazycommit+0x7e0/0xb80 fs/jfs/jfs_txnmgr.c:2736
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Allocated by task 6029:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:257 [inline]
 __kmalloc_cache_noprof+0x19c/0x2c0 mm/slub.c:4295
 kmalloc_noprof include/linux/slab.h:878 [inline]
 kzalloc_noprof include/linux/slab.h:1014 [inline]
 jfs_fill_super+0xff/0xc50 fs/jfs/super.c:495
 mount_bdev+0x20a/0x2d0 fs/super.c:1679
 legacy_get_tree+0xee/0x190 fs/fs_context.c:662
 vfs_get_tree+0x90/0x2b0 fs/super.c:1800
 do_new_mount+0x2be/0xb40 fs/namespace.c:3507
 do_mount fs/namespace.c:3847 [inline]
 __do_sys_mount fs/namespace.c:4057 [inline]
 __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4034
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5412:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:2342 [inline]
 slab_free mm/slub.c:4579 [inline]
 kfree+0x1a0/0x440 mm/slub.c:4727
 generic_shutdown_super+0x139/0x2d0 fs/super.c:642
 kill_block_super+0x44/0x90 fs/super.c:1696
 deactivate_locked_super+0xc4/0x130 fs/super.c:473
 cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1373
 task_work_run+0x24f/0x310 kernel/task_work.c:239
 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+0x168/0x370 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888038ac2800
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 148 bytes inside of
 freed 256-byte region [ffff888038ac2800, ffff888038ac2900)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x38ac2
anon flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 04fff00000000000 ffff88801ac41b40 ffffea00010c5e80 0000000000000005
raw: 0000000000000000 0000000080080008 00000001f5000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5427, tgid 5427 (syz-executor), ts 87036722804, free_ts 87035650225
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537
 prep_new_page mm/page_alloc.c:1545 [inline]
 get_page_from_freelist+0x3045/0x3190 mm/page_alloc.c:3457
 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4733
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
 alloc_slab_page+0x6a/0x120 mm/slub.c:2412
 allocate_slab+0x5a/0x2f0 mm/slub.c:2578
 new_slab mm/slub.c:2631 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3818
 __slab_alloc+0x58/0xa0 mm/slub.c:3908
 __slab_alloc_node mm/slub.c:3961 [inline]
 slab_alloc_node mm/slub.c:4122 [inline]
 __kmalloc_cache_noprof+0x1d5/0x2c0 mm/slub.c:4290
 kmalloc_noprof include/linux/slab.h:878 [inline]
 kzalloc_noprof include/linux/slab.h:1014 [inline]
 vlan_info_alloc net/8021q/vlan_core.c:153 [inline]
 vlan_vid_add+0x147/0x760 net/8021q/vlan_core.c:329
 vlan_device_event+0x1ca3/0x1de0 net/8021q/vlan.c:385
 notifier_call_chain+0x19f/0x3e0 kernel/notifier.c:93
 __dev_notify_flags+0x207/0x400
 dev_change_flags+0xf0/0x1a0 net/core/dev.c:8918
 do_setlink+0xcd0/0x41f0 net/core/rtnetlink.c:2929
 __rtnl_newlink net/core/rtnetlink.c:3725 [inline]
 rtnl_newlink+0x180d/0x20a0 net/core/rtnetlink.c:3772
page last free pid 5412 tgid 5412 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1108 [inline]
 free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2638
 vfree+0x186/0x2e0 mm/vmalloc.c:3361
 copy_entries_to_user net/ipv6/netfilter/ip6_tables.c:882 [inline]
 get_entries net/ipv6/netfilter/ip6_tables.c:1039 [inline]
 do_ip6t_get_ctl+0x11eb/0x1820 net/ipv6/netfilter/ip6_tables.c:1677
 nf_getsockopt+0x299/0x2c0 net/netfilter/nf_sockopt.c:116
 ipv6_getsockopt+0x23e/0x360 net/ipv6/ipv6_sockglue.c:1493
 tcp_getsockopt+0x163/0x1c0 net/ipv4/tcp.c:4670
 do_sock_getsockopt+0x3c4/0x7e0 net/socket.c:2396
 __sys_getsockopt+0x267/0x330 net/socket.c:2425
 __do_sys_getsockopt net/socket.c:2435 [inline]
 __se_sys_getsockopt net/socket.c:2432 [inline]
 __x64_sys_getsockopt+0xb5/0xd0 net/socket.c:2432
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888038ac2780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888038ac2800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888038ac2880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff888038ac2900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888038ac2980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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