==================================================================
BUG: KASAN: slab-use-after-free in __lock_acquire+0x2de0/0x3cb0 kernel/locking/lockdep.c:5007
Read of size 8 at addr ffff888011cae418 by task kworker/0:3/5437

CPU: 0 UID: 0 PID: 5437 Comm: kworker/0:3 Not tainted 6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events purge_vmap_node
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119
 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
 __lock_acquire+0x2de0/0x3cb0 kernel/locking/lockdep.c:5007
 lock_acquire kernel/locking/lockdep.c:5759 [inline]
 lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
 p9_tag_remove net/9p/client.c:397 [inline]
 p9_req_put net/9p/client.c:405 [inline]
 p9_req_put+0xaf/0x250 net/9p/client.c:402
 req_done+0x1e7/0x2f0 net/9p/trans_virtio.c:147
 vring_interrupt drivers/virtio/virtio_ring.c:2595 [inline]
 vring_interrupt+0x31b/0x400 drivers/virtio/virtio_ring.c:2570
 __handle_irq_event_percpu+0x229/0x7c0 kernel/irq/handle.c:158
 handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
 handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:210
 handle_edge_irq+0x263/0xd10 kernel/irq/chip.c:831
 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline]
 handle_irq arch/x86/kernel/irq.c:247 [inline]
 call_irq_handler arch/x86/kernel/irq.c:259 [inline]
 __common_interrupt+0xdf/0x250 arch/x86/kernel/irq.c:285
 common_interrupt+0xab/0xd0 arch/x86/kernel/irq.c:278
 </IRQ>
 <TASK>
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
RIP: 0010:PageCompound include/linux/page-flags.h:285 [inline]
RIP: 0010:free_pages_prepare mm/page_alloc.c:1042 [inline]
RIP: 0010:free_unref_page+0x8f/0xe40 mm/page_alloc.c:2619
Code: 0f 85 4e 0b 00 00 48 8b 03 a8 40 0f 85 0f 04 00 00 4c 8d 73 08 48 b8 00 00 00 00 00 fc ff df 4c 89 f2 48 c1 ea 03 80 3c 02 00 <0f> 85 c0 0b 00 00 4c 8b 6b 08 41 83 e5 01 48 b8 00 00 00 00 00 fc
RSP: 0018:ffffc9000401fa30 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: ffffea000179f440 RCX: ffffffff81dd1f80
RDX: 1ffffd40002f3e89 RSI: 0000000000000008 RDI: ffffea000179f440
RBP: 0000000000000000 R08: 0000000000000000 R09: fffff940002f3e88
R10: ffffea000179f447 R11: 0000000000000000 R12: 0000000000000000
R13: fffff52005d70000 R14: ffffea000179f448 R15: 800000005e7d1103
 kasan_depopulate_vmalloc_pte+0x63/0x80 mm/kasan/shadow.c:408
 apply_to_pte_range mm/memory.c:2797 [inline]
 apply_to_pmd_range mm/memory.c:2841 [inline]
 apply_to_pud_range mm/memory.c:2877 [inline]
 apply_to_p4d_range mm/memory.c:2913 [inline]
 __apply_to_page_range+0x795/0xdd0 mm/memory.c:2947
 kasan_release_vmalloc+0xac/0xc0 mm/kasan/shadow.c:525
 purge_vmap_node+0x3ec/0x920 mm/vmalloc.c:2209
 process_one_work+0x958/0x1ad0 kernel/workqueue.c:3231
 process_scheduled_works kernel/workqueue.c:3312 [inline]
 worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Allocated by task 7803:
 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_noprof include/linux/slab.h:681 [inline]
 p9_client_create+0xcf/0x11b0 net/9p/client.c:983
 v9fs_session_init+0x1f8/0x1a80 fs/9p/v9fs.c:410
 v9fs_mount+0xc6/0xa50 fs/9p/vfs_super.c:122
 legacy_get_tree+0x109/0x220 fs/fs_context.c:662
 vfs_get_tree+0x8f/0x380 fs/super.c:1800
 do_new_mount fs/namespace.c:3472 [inline]
 path_mount+0x6e1/0x1f10 fs/namespace.c:3799
 do_mount fs/namespace.c:3812 [inline]
 __do_sys_mount fs/namespace.c:4020 [inline]
 __se_sys_mount fs/namespace.c:3997 [inline]
 __ia32_sys_mount+0x292/0x310 fs/namespace.c:3997
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Freed by task 7803:
 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+0xf7/0x160 mm/kasan/common.c:240
 __kasan_slab_free+0x32/0x50 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2256 [inline]
 slab_free mm/slub.c:4477 [inline]
 kfree+0x12a/0x3b0 mm/slub.c:4598
 p9_client_create+0x9ca/0x11b0 net/9p/client.c:1054
 v9fs_session_init+0x1f8/0x1a80 fs/9p/v9fs.c:410
 v9fs_mount+0xc6/0xa50 fs/9p/vfs_super.c:122
 legacy_get_tree+0x109/0x220 fs/fs_context.c:662
 vfs_get_tree+0x8f/0x380 fs/super.c:1800
 do_new_mount fs/namespace.c:3472 [inline]
 path_mount+0x6e1/0x1f10 fs/namespace.c:3799
 do_mount fs/namespace.c:3812 [inline]
 __do_sys_mount fs/namespace.c:4020 [inline]
 __se_sys_mount fs/namespace.c:3997 [inline]
 __ia32_sys_mount+0x292/0x310 fs/namespace.c:3997
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

The buggy address belongs to the object at ffff888011cae400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 24 bytes inside of
 freed 512-byte region [ffff888011cae400, ffff888011cae600)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11cac
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xfdffffff(slab)
raw: 00fff00000000040 ffff88801ac42c80 ffffea0000a40700 dead000000000002
raw: 0000000000000000 0000000080100010 00000001fdffffff 0000000000000000
head: 00fff00000000040 ffff88801ac42c80 ffffea0000a40700 dead000000000002
head: 0000000000000000 0000000080100010 00000001fdffffff 0000000000000000
head: 00fff00000000002 ffffea0000472b01 ffffffffffffffff 0000000000000000
head: 0000000000000004 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5425, tgid 5425 (syz-executor), ts 61510928376, free_ts 61468892430
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1500
 prep_new_page mm/page_alloc.c:1508 [inline]
 get_page_from_freelist+0x1351/0x2e50 mm/page_alloc.c:3446
 __alloc_pages_noprof+0x22b/0x2460 mm/page_alloc.c:4702
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 alloc_slab_page+0x4e/0xf0 mm/slub.c:2325
 allocate_slab mm/slub.c:2488 [inline]
 new_slab+0x84/0x260 mm/slub.c:2541
 ___slab_alloc+0xdac/0x1870 mm/slub.c:3727
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3817
 __slab_alloc_node mm/slub.c:3870 [inline]
 slab_alloc_node mm/slub.c:4029 [inline]
 __kmalloc_cache_noprof+0x2c5/0x310 mm/slub.c:4188
 kmalloc_noprof include/linux/slab.h:681 [inline]
 kzalloc_noprof include/linux/slab.h:807 [inline]
 mca_alloc net/ipv6/mcast.c:880 [inline]
 __ipv6_dev_mc_inc+0x2b7/0xc10 net/ipv6/mcast.c:936
 ipv6_add_dev+0xa93/0x1400 net/ipv6/addrconf.c:468
 addrconf_notify+0x546/0x19d0 net/ipv6/addrconf.c:3653
 notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1994
 call_netdevice_notifiers_extack net/core/dev.c:2032 [inline]
 call_netdevice_notifiers net/core/dev.c:2046 [inline]
 register_netdevice+0x1728/0x1e20 net/core/dev.c:10477
 veth_newlink+0x366/0x9e0 drivers/net/veth.c:1829
 rtnl_newlink_create net/core/rtnetlink.c:3510 [inline]
 __rtnl_newlink+0x119c/0x1920 net/core/rtnetlink.c:3730
page last free pid 5424 tgid 5424 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1101 [inline]
 free_unref_page+0x64a/0xe40 mm/page_alloc.c:2619
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3992 [inline]
 slab_alloc_node mm/slub.c:4041 [inline]
 __kmalloc_cache_noprof+0x11e/0x310 mm/slub.c:4188
 kmalloc_noprof include/linux/slab.h:681 [inline]
 kzalloc_noprof include/linux/slab.h:807 [inline]
 ref_tracker_alloc+0x17c/0x5b0 lib/ref_tracker.c:203
 __netdev_tracker_alloc include/linux/netdevice.h:4047 [inline]
 netdev_hold include/linux/netdevice.h:4076 [inline]
 netdev_hold include/linux/netdevice.h:4071 [inline]
 netdev_queue_add_kobject net/core/net-sysfs.c:1783 [inline]
 netdev_queue_update_kobjects+0x281/0x640 net/core/net-sysfs.c:1838
 register_queue_kobjects net/core/net-sysfs.c:1900 [inline]
 netdev_register_kobject+0x290/0x3f0 net/core/net-sysfs.c:2140
 register_netdevice+0x1473/0x1e20 net/core/dev.c:10444
 veth_newlink+0x4fb/0x9e0 drivers/net/veth.c:1860
 rtnl_newlink_create net/core/rtnetlink.c:3510 [inline]
 __rtnl_newlink+0x119c/0x1920 net/core/rtnetlink.c:3730
 rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3743
 rtnetlink_rcv_msg+0x3c7/0xea0 net/core/rtnetlink.c:6647
 netlink_rcv_skb+0x165/0x410 net/netlink/af_netlink.c:2550
 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
 netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1357
 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1901

Memory state around the buggy address:
 ffff888011cae300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888011cae380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888011cae400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff888011cae480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888011cae500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	0f 85 4e 0b 00 00    	jne    0xb54
   6:	48 8b 03             	mov    (%rbx),%rax
   9:	a8 40                	test   $0x40,%al
   b:	0f 85 0f 04 00 00    	jne    0x420
  11:	4c 8d 73 08          	lea    0x8(%rbx),%r14
  15:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  1c:	fc ff df
  1f:	4c 89 f2             	mov    %r14,%rdx
  22:	48 c1 ea 03          	shr    $0x3,%rdx
  26:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
* 2a:	0f 85 c0 0b 00 00    	jne    0xbf0 <-- trapping instruction
  30:	4c 8b 6b 08          	mov    0x8(%rbx),%r13
  34:	41 83 e5 01          	and    $0x1,%r13d
  38:	48                   	rex.W
  39:	b8 00 00 00 00       	mov    $0x0,%eax
  3e:	00 fc                	add    %bh,%ah