==================================================================
BUG: KASAN: use-after-free in tcp_retransmit_timer+0x2ea2/0x3320 net/ipv4/tcp_timer.c:511
Read of size 8 at addr ffff88807e6fc3b8 by task syz-executor.1/16333

CPU: 0 PID: 16333 Comm: syz-executor.1 Not tainted 5.17.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description.constprop.0.cold+0x8d/0x303 mm/kasan/report.c:255
 __kasan_report mm/kasan/report.c:442 [inline]
 kasan_report.cold+0x83/0xdf mm/kasan/report.c:459
 tcp_retransmit_timer+0x2ea2/0x3320 net/ipv4/tcp_timer.c:511
 tcp_write_timer_handler+0x5e6/0xbc0 net/ipv4/tcp_timer.c:622
 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:642
 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421
 expire_timers kernel/time/timer.c:1466 [inline]
 __run_timers.part.0+0x67c/0xa30 kernel/time/timer.c:1734
 __run_timers kernel/time/timer.c:1715 [inline]
 run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:lock_acquire+0x1ef/0x510 kernel/locking/lockdep.c:5607
Code: 01 a6 7e 83 f8 01 0f 85 b4 02 00 00 9c 58 f6 c4 02 0f 85 9f 02 00 00 48 83 7c 24 08 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24
RSP: 0018:ffffc90002927c60 EFLAGS: 00000206
RAX: dffffc0000000000 RBX: 1ffff92000524f8e RCX: 000000000000eee2
RDX: 1ffff1100ec5d15b RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff8ffd394f
R10: fffffbfff1ffa729 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000000 R14: ffff88814af78958 R15: 0000000000000000
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:349 [inline]
 inode_sb_list_del fs/inode.c:502 [inline]
 evict+0x179/0x6b0 fs/inode.c:653
 iput_final fs/inode.c:1744 [inline]
 iput.part.0+0x562/0x820 fs/inode.c:1770
 iput+0x58/0x70 fs/inode.c:1760
 do_unlinkat+0x418/0x650 fs/namei.c:4225
 __do_sys_unlink fs/namei.c:4266 [inline]
 __se_sys_unlink fs/namei.c:4264 [inline]
 __x64_sys_unlink+0xc6/0x110 fs/namei.c:4264
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fb097b2c997
Code: 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 57 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc865e8848 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb097b2c997
RDX: 00007ffc865e8880 RSI: 00007ffc865e8880 RDI: 00007ffc865e8910
RBP: 00007ffc865e8910 R08: 0000000000000001 R09: 00007ffc865e86e0
R10: 000055555709c853 R11: 0000000000000206 R12: 00007fb097b861ea
R13: 00007ffc865e99d0 R14: 000055555709c810 R15: 00007ffc865e9a10
 </TASK>

Allocated by task 17080:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:436 [inline]
 __kasan_slab_alloc+0x85/0xb0 mm/kasan/common.c:469
 kasan_slab_alloc include/linux/kasan.h:260 [inline]
 slab_post_alloc_hook mm/slab.h:732 [inline]
 slab_alloc mm/slab.c:3315 [inline]
 kmem_cache_alloc+0x265/0x560 mm/slab.c:3499
 kmem_cache_zalloc include/linux/slab.h:705 [inline]
 net_alloc net/core/net_namespace.c:406 [inline]
 copy_net_ns+0x125/0x760 net/core/net_namespace.c:461
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226
 ksys_unshare+0x445/0x920 kernel/fork.c:3048
 __do_sys_unshare kernel/fork.c:3119 [inline]
 __se_sys_unshare kernel/fork.c:3117 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3117
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

The buggy address belongs to the object at ffff88807e6fc100
 which belongs to the cache net_namespace of size 6528
The buggy address is located 696 bytes inside of
 6528-byte region [ffff88807e6fc100, ffff88807e6fda80)
The buggy address belongs to the page:
page:ffffea0001f9bf00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88807e6fc100 pfn:0x7e6fc
head:ffffea0001f9bf00 order:1 compound_mapcount:0
memcg:ffff88807a5ae081
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffff888015dfd560 ffff888015dfd560 ffff888015b90f00
raw: ffff88807e6fc100 ffff88807e6fc100 0000000100000000 ffff88807a5ae081
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0x3420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_HARDWALL|__GFP_THISNODE), pid 17080, ts 561766480995, free_ts 561695456736
 prep_new_page mm/page_alloc.c:2434 [inline]
 get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5389
 __alloc_pages_node include/linux/gfp.h:572 [inline]
 kmem_getpages mm/slab.c:1378 [inline]
 cache_grow_begin+0x75/0x350 mm/slab.c:2584
 cache_alloc_refill+0x27f/0x380 mm/slab.c:2957
 ____cache_alloc mm/slab.c:3040 [inline]
 ____cache_alloc mm/slab.c:3023 [inline]
 __do_cache_alloc mm/slab.c:3267 [inline]
 slab_alloc mm/slab.c:3308 [inline]
 kmem_cache_alloc+0x450/0x560 mm/slab.c:3499
 kmem_cache_zalloc include/linux/slab.h:705 [inline]
 net_alloc net/core/net_namespace.c:406 [inline]
 copy_net_ns+0x125/0x760 net/core/net_namespace.c:461
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226
 ksys_unshare+0x445/0x920 kernel/fork.c:3048
 __do_sys_unshare kernel/fork.c:3119 [inline]
 __se_sys_unshare kernel/fork.c:3117 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3117
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1352 [inline]
 free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1404
 free_unref_page_prepare mm/page_alloc.c:3325 [inline]
 free_unref_page+0x19/0x690 mm/page_alloc.c:3404
 slab_destroy mm/slab.c:1630 [inline]
 slabs_destroy+0x89/0xc0 mm/slab.c:1650
 cache_flusharray mm/slab.c:3410 [inline]
 ___cache_free+0x312/0x5c0 mm/slab.c:3472
 qlink_free mm/kasan/quarantine.c:157 [inline]
 qlist_free_all+0x50/0x1a0 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x97/0xb0 mm/kasan/common.c:446
 kasan_slab_alloc include/linux/kasan.h:260 [inline]
 slab_post_alloc_hook mm/slab.h:732 [inline]
 slab_alloc_node mm/slab.c:3253 [inline]
 kmem_cache_alloc_node+0x2ea/0x590 mm/slab.c:3591
 __alloc_skb+0x215/0x340 net/core/skbuff.c:414
 alloc_skb include/linux/skbuff.h:1158 [inline]
 bt_skb_alloc include/net/bluetooth/bluetooth.h:422 [inline]
 vhci_get_user drivers/bluetooth/hci_vhci.c:391 [inline]
 vhci_write+0xbd/0x450 drivers/bluetooth/hci_vhci.c:511
 call_write_iter include/linux/fs.h:2074 [inline]
 do_iter_readv_writev+0x47a/0x750 fs/read_write.c:725
 do_iter_write+0x188/0x710 fs/read_write.c:851
 vfs_writev+0x1aa/0x630 fs/read_write.c:924
 do_writev+0x139/0x300 fs/read_write.c:967
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Memory state around the buggy address:
 ffff88807e6fc280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807e6fc300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807e6fc380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                        ^
 ffff88807e6fc400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807e6fc480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	01 a6 7e 83 f8 01    	add    %esp,0x1f8837e(%rsi)
   6:	0f 85 b4 02 00 00    	jne    0x2c0
   c:	9c                   	pushfq
   d:	58                   	pop    %rax
   e:	f6 c4 02             	test   $0x2,%ah
  11:	0f 85 9f 02 00 00    	jne    0x2b6
  17:	48 83 7c 24 08 00    	cmpq   $0x0,0x8(%rsp)
  1d:	74 01                	je     0x20
  1f:	fb                   	sti
  20:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  27:	fc ff df
* 2a:	48 01 c3             	add    %rax,%rbx <-- trapping instruction
  2d:	48 c7 03 00 00 00 00 	movq   $0x0,(%rbx)
  34:	48 c7 43 08 00 00 00 	movq   $0x0,0x8(%rbx)
  3b:	00
  3c:	48                   	rex.W
  3d:	8b                   	.byte 0x8b
  3e:	84                   	.byte 0x84
  3f:	24                   	.byte 0x24