loop0: detected capacity change from 0 to 32768
==================================================================
BUG: KASAN: slab-out-of-b[  196.336066][ T6886] BUG: KASAN: slab-out-of-bounds in dtMoveEntry fs/jfs/jfs_dtree.c:3934 [inline]
BUG: KASAN: slab-out-of-b[  196.336066][ T6886] BUG: KASAN: slab-out-of-bounds in dtSplitPage+0x1e37/0x3b20 fs/jfs/jfs_dtree.c:1561
Write of size 1 at addr ffff8880271050c0 by task syz.0.123/6886

CPU: 1 UID: 0 PID: 6886 Comm: syz.0.123 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x240 mm/kasan/report.c:482
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 dtMoveEntry fs/jfs/jfs_dtree.c:3934 [inline]
 dtSplitPage+0x1e37/0x3b20 fs/jfs/jfs_dtree.c:1561
 dtSplitUp fs/jfs/jfs_dtree.c:1092 [inline]
 dtInsert+0x109b/0x5f40 fs/jfs/jfs_dtree.c:871
 jfs_create+0x6c8/0xa80 fs/jfs/namei.c:137
 lookup_open fs/namei.c:3796 [inline]
 open_last_lookups fs/namei.c:3895 [inline]
 path_openat+0x1500/0x3840 fs/namei.c:4131
 do_filp_open+0x1fa/0x410 fs/namei.c:4161
 do_sys_openat2+0x121/0x1c0 fs/open.c:1435
 do_sys_open fs/open.c:1450 [inline]
 __do_sys_creat fs/open.c:1528 [inline]
 __se_sys_creat fs/open.c:1522 [inline]
 __x64_sys_creat+0x8f/0xc0 fs/open.c:1522
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f419741eec9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f419567e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007f4197675fa0 RCX: 00007f419741eec9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000580
RBP: 00007f41974a1f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4197676038 R14: 00007f4197675fa0 R15: 00007ffef13c7638
 </TASK>

Allocated by task 5808:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:388 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4376 [inline]
 __kmalloc_noprof+0x1c1/0x3f0 mm/slub.c:4388
 kmalloc_noprof include/linux/slab.h:909 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 new_dir fs/proc/proc_sysctl.c:966 [inline]
 get_subdir fs/proc/proc_sysctl.c:1010 [inline]
 sysctl_mkdir_p fs/proc/proc_sysctl.c:1320 [inline]
 __register_sysctl_table+0xba1/0x1340 fs/proc/proc_sysctl.c:1395
 mpls_dev_sysctl_register+0x188/0x270 net/mpls/af_mpls.c:1405
 mpls_add_dev net/mpls/af_mpls.c:1460 [inline]
 mpls_dev_notify+0x357/0x7a0 net/mpls/af_mpls.c:1600
 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline]
 call_netdevice_notifiers net/core/dev.c:2281 [inline]
 register_netdevice+0x163c/0x1b10 net/core/dev.c:11244
 wg_newlink+0x3a7/0x660 drivers/net/wireguard/device.c:370
 rtnl_newlink_create+0x30d/0xb00 net/core/rtnetlink.c:3825
 __rtnl_newlink net/core/rtnetlink.c:3942 [inline]
 rtnl_newlink+0x16d6/0x1c70 net/core/rtnetlink.c:4057
 rtnetlink_rcv_msg+0x7cc/0xb70 net/core/rtnetlink.c:6946
 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x846/0xa10 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:729
 __sys_sendto+0x3c7/0x520 net/socket.c:2231
 __do_sys_sendto net/socket.c:2238 [inline]
 __se_sys_sendto net/socket.c:2234 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2234
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888027105000
 which belongs to the cache kmalloc-192 of size 192
The buggy address is located 4 bytes to the right of
 allocated 188-byte region [ffff888027105000, ffff8880271050bc)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x27105
anon flags: 0x80000000000000(node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000000 ffff8880194413c0 ffffea00009f2e80 dead000000000005
raw: 0000000000000000 0000000000100010 00000000f5000000 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 0x252800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_THISNODE), pid 67, tgid 67 (kworker/u8:4), ts 14745731562, free_ts 14218604332
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851
 prep_new_page mm/page_alloc.c:1859 [inline]
 get_page_from_freelist+0x26dc/0x2770 mm/page_alloc.c:3858
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148
 alloc_slab_page mm/slub.c:2494 [inline]
 allocate_slab+0x65/0x370 mm/slub.c:2660
 new_slab mm/slub.c:2714 [inline]
 ___slab_alloc+0xab4/0x1320 mm/slub.c:3901
 __slab_alloc+0xb9/0x180 mm/slub.c:3992
 __slab_alloc_node mm/slub.c:4067 [inline]
 slab_alloc_node mm/slub.c:4228 [inline]
 __do_kmalloc_node mm/slub.c:4375 [inline]
 __kvmalloc_node_noprof+0x1aa/0x500 mm/slub.c:5067
 sbitmap_init_node+0x2c9/0x630 lib/sbitmap.c:132
 blk_mq_alloc_hctx block/blk-mq.c:4032 [inline]
 blk_mq_alloc_and_init_hctx+0x4fb/0xd80 block/blk-mq.c:4504
 __blk_mq_realloc_hw_ctxs+0x169/0x400 block/blk-mq.c:4535
 blk_mq_realloc_hw_ctxs block/blk-mq.c:4562 [inline]
 blk_mq_init_allocated_queue+0x416/0x14e0 block/blk-mq.c:4594
 blk_mq_alloc_queue+0x191/0x280 block/blk-mq.c:4404
 scsi_alloc_sdev+0x785/0xb60 drivers/scsi/scsi_scan.c:339
 scsi_probe_and_add_lun+0x1c5/0x4580 drivers/scsi/scsi_scan.c:1211
 __scsi_scan_target+0x1dd/0xd10 drivers/scsi/scsi_scan.c:1776
 scsi_scan_channel drivers/scsi/scsi_scan.c:1864 [inline]
 scsi_scan_host_selected+0x375/0x690 drivers/scsi/scsi_scan.c:1893
page last free pid 1228 tgid 1228 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0xfcf/0x1160 mm/page_alloc.c:2895
 vfree+0x2ad/0x470 mm/vmalloc.c:3434
 delayed_vfree_work+0x55/0x80 mm/vmalloc.c:3353
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff888027104f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888027105000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888027105080: 00 00 00 00 00 00 00 04 fc fc fc fc fc fc fc fc
                                           ^
 ffff888027105100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888027105180: 00 00 00 00 00 00 00 04 fc fc fc fc fc fc fc fc
==================================================================