==================================================================
BUG: KASAN: slab-use-after-free in __lock_acquire+0x2de0/0x3cb0 kernel/locking/lockdep.c:5007
Read of size 8 at addr ffff8880286dbc18 by task udevd/4833

CPU: 0 UID: 0 PID: 4833 Comm: udevd Not tainted 6.11.0-rc5-syzkaller-00081-gd5d547aa7b51 #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:
 <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:strcmp+0x68/0xb0 lib/string.c:267
Code: 38 d0 7f 04 84 c0 75 58 0f b6 6b ff 4c 8d 66 01 48 89 f0 48 89 f2 48 c1 e8 03 83 e2 07 42 0f b6 04 28 38 d0 7f 04 84 c0 75 2c <41> 3a 6c 24 ff 74 ae 19 c0 48 83 c4 08 5b 83 c8 01 5d 41 5c 41 5d
RSP: 0018:ffffc90004b9f930 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff888012bdbc59 RCX: ffffffff82244f04
RDX: 0000000000000000 RSI: ffffffff8bdb1e40 RDI: ffff888012bdbc58
RBP: 0000000000000064 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8bdb1e41
R13: dffffc0000000000 R14: ffff888016e900d8 R15: ffff88802b89552d
 kernfs_dop_revalidate+0x22f/0x5a0 fs/kernfs/dir.c:1170
 d_revalidate fs/namei.c:868 [inline]
 d_revalidate fs/namei.c:865 [inline]
 lookup_fast+0x239/0x540 fs/namei.c:1679
 walk_component+0x5b/0x5b0 fs/namei.c:2035
 link_path_walk.part.0.constprop.0+0x669/0xd40 fs/namei.c:2404
 link_path_walk fs/namei.c:2335 [inline]
 path_lookupat+0x93/0x770 fs/namei.c:2565
 filename_lookup+0x1e5/0x5b0 fs/namei.c:2595
 vfs_statx+0x11e/0x1e0 fs/stat.c:312
 vfs_fstatat+0x9f/0x160 fs/stat.c:341
 __do_sys_newfstatat+0xa2/0x130 fs/stat.c:505
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe3cb3165f4
Code: 64 c7 00 09 00 00 00 83 c8 ff c3 48 89 f2 b9 00 01 00 00 48 89 fe bf 9c ff ff ff e9 00 00 00 00 41 89 ca b8 06 01 00 00 0f 05 <45> 31 c0 3d 00 f0 ff ff 76 10 48 8b 15 03 a8 0d 00 f7 d8 41 83 c8
RSP: 002b:00007ffd57b04e58 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe3cb3165f4
RDX: 00007ffd57b04e68 RSI: 00007ffd57b052f8 RDI: 00000000ffffff9c
RBP: 00007ffd57b04ef8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd57b052f8
R13: 00007ffd57b04e68 R14: 000055f2121fb910 R15: 0000000000000000
 </TASK>

Allocated by task 5563:
 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 5563:
 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:2252 [inline]
 slab_free mm/slub.c:4473 [inline]
 kfree+0x12a/0x3b0 mm/slub.c:4594
 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 ffff8880286dbc00
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 24 bytes inside of
 freed 512-byte region [ffff8880286dbc00, ffff8880286dbe00)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x286d8
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 ffff888015842c80 dead000000000100 dead000000000122
raw: 0000000000000000 0000000080100010 00000001fdffffff 0000000000000000
head: 00fff00000000040 ffff888015842c80 dead000000000100 dead000000000122
head: 0000000000000000 0000000080100010 00000001fdffffff 0000000000000000
head: 00fff00000000002 ffffea0000a1b601 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 5389, tgid 5389 (syz-executor), ts 61701861558, free_ts 61558648849
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1493
 prep_new_page mm/page_alloc.c:1501 [inline]
 get_page_from_freelist+0x1351/0x2e50 mm/page_alloc.c:3439
 __alloc_pages_noprof+0x22b/0x2460 mm/page_alloc.c:4695
 __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:2321
 allocate_slab mm/slub.c:2484 [inline]
 new_slab+0x84/0x260 mm/slub.c:2537
 ___slab_alloc+0xdac/0x1870 mm/slub.c:3723
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3813
 __slab_alloc_node mm/slub.c:3866 [inline]
 slab_alloc_node mm/slub.c:4025 [inline]
 __do_kmalloc_node mm/slub.c:4157 [inline]
 __kmalloc_noprof+0x379/0x410 mm/slub.c:4170
 kmalloc_noprof include/linux/slab.h:685 [inline]
 kzalloc_noprof include/linux/slab.h:807 [inline]
 fib6_info_alloc+0x40/0x160 net/ipv6/ip6_fib.c:155
 ip6_route_info_create+0x337/0x1aa0 net/ipv6/route.c:3761
 addrconf_f6i_alloc+0x393/0x670 net/ipv6/route.c:4588
 ipv6_add_addr+0x538/0x2060 net/ipv6/addrconf.c:1120
 inet6_addr_add+0x3bb/0xbc0 net/ipv6/addrconf.c:3060
 inet6_rtm_newaddr+0x11d4/0x1aa0 net/ipv6/addrconf.c:5048
 rtnetlink_rcv_msg+0x3c7/0xea0 net/core/rtnetlink.c:6647
 netlink_rcv_skb+0x165/0x410 net/netlink/af_netlink.c:2550
page last free pid 5433 tgid 5433 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1094 [inline]
 free_unref_page+0x64a/0xe40 mm/page_alloc.c:2612
 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:3988 [inline]
 slab_alloc_node mm/slub.c:4037 [inline]
 kmem_cache_alloc_noprof+0x121/0x2f0 mm/slub.c:4044
 getname_flags.part.0+0x4c/0x550 fs/namei.c:139
 getname_flags include/linux/audit.h:322 [inline]
 getname+0x8d/0xe0 fs/namei.c:225
 do_sys_openat2+0x104/0x1e0 fs/open.c:1410
 do_sys_open fs/open.c:1431 [inline]
 __do_sys_openat fs/open.c:1447 [inline]
 __se_sys_openat fs/open.c:1442 [inline]
 __x64_sys_openat+0x175/0x210 fs/open.c:1442
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff8880286dbb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880286dbb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880286dbc00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff8880286dbc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880286dbd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	38 d0                	cmp    %dl,%al
   2:	7f 04                	jg     0x8
   4:	84 c0                	test   %al,%al
   6:	75 58                	jne    0x60
   8:	0f b6 6b ff          	movzbl -0x1(%rbx),%ebp
   c:	4c 8d 66 01          	lea    0x1(%rsi),%r12
  10:	48 89 f0             	mov    %rsi,%rax
  13:	48 89 f2             	mov    %rsi,%rdx
  16:	48 c1 e8 03          	shr    $0x3,%rax
  1a:	83 e2 07             	and    $0x7,%edx
  1d:	42 0f b6 04 28       	movzbl (%rax,%r13,1),%eax
  22:	38 d0                	cmp    %dl,%al
  24:	7f 04                	jg     0x2a
  26:	84 c0                	test   %al,%al
  28:	75 2c                	jne    0x56
* 2a:	41 3a 6c 24 ff       	cmp    -0x1(%r12),%bpl <-- trapping instruction
  2f:	74 ae                	je     0xffffffdf
  31:	19 c0                	sbb    %eax,%eax
  33:	48 83 c4 08          	add    $0x8,%rsp
  37:	5b                   	pop    %rbx
  38:	83 c8 01             	or     $0x1,%eax
  3b:	5d                   	pop    %rbp
  3c:	41 5c                	pop    %r12
  3e:	41 5d                	pop    %r13