==================================================================
BUG: KASAN: use-after-free in tcp_probe_timer net/ipv4/tcp_timer.c:378 [inline]
BUG: KASAN: use-after-free in tcp_write_timer_handler net/ipv4/tcp_timer.c:624 [inline]
BUG: KASAN: use-after-free in tcp_write_timer_handler+0x998/0x9f0 net/ipv4/tcp_timer.c:594
Read of size 1 at addr ffff888020d52385 by task syz-executor.3/26652

CPU: 0 PID: 26652 Comm: syz-executor.3 Not tainted 6.0.0-syzkaller-02801-gfa182ea26ff0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:317 [inline]
 print_report.cold+0x2ba/0x719 mm/kasan/report.c:433
 kasan_report+0xb1/0x1e0 mm/kasan/report.c:495
 tcp_probe_timer net/ipv4/tcp_timer.c:378 [inline]
 tcp_write_timer_handler net/ipv4/tcp_timer.c:624 [inline]
 tcp_write_timer_handler+0x998/0x9f0 net/ipv4/tcp_timer.c:594
 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:637
 call_timer_fn+0x1a0/0x6b0 kernel/time/timer.c:1474
 expire_timers kernel/time/timer.c:1519 [inline]
 __run_timers.part.0+0x674/0xa80 kernel/time/timer.c:1790
 __run_timers kernel/time/timer.c:1768 [inline]
 run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1803
 __do_softirq+0x1d0/0x9c8 kernel/softirq.c:571
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:662
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1107
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:write_comp_data+0x3c/0x90 kernel/kcov.c:229
Code: 01 00 00 49 89 f8 65 48 8b 14 25 80 6f 02 00 a9 00 01 ff 00 74 0e 85 f6 74 59 8b 82 bc 15 00 00 85 c0 74 4f 8b 82 98 15 00 00 <83> f8 03 75 44 48 8b 82 a0 15 00 00 8b 92 9c 15 00 00 48 8b 38 48
RSP: 0018:ffffc90011d8fe28 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff816facfc
RDX: ffff888058740000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: ffffffff89ef6c60 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000005 R14: 0000000000000005 R15: 00007fff671c1080
 __sanitizer_cov_trace_switch+0x50/0x90 kernel/kcov.c:333
 futex_cmd_has_timeout kernel/futex/syscalls.c:139 [inline]
 __do_sys_futex kernel/futex/syscalls.c:172 [inline]
 __se_sys_futex kernel/futex/syscalls.c:164 [inline]
 __x64_sys_futex+0x17c/0x4a0 kernel/futex/syscalls.c:164
 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+0x63/0xcd
RIP: 0033:0x7f7269e8b5a9
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff670f1b48 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f7269fabf8c RCX: 00007f7269e8b5a9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f7269fabf8c
RBP: 00007f7269fabf80 R08: 00007fff671c1080 R09: 0000000000000000
R10: 00007fff670f1c30 R11: 0000000000000246 R12: 00000000000b8d65
R13: 00007fff670f1c30 R14: 00007fff670f1c50 R15: 0000000000000032
 </TASK>

Allocated by task 25253:
 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:437 [inline]
 __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:470
 kasan_slab_alloc include/linux/kasan.h:224 [inline]
 slab_post_alloc_hook mm/slab.h:727 [inline]
 slab_alloc_node mm/slub.c:3248 [inline]
 slab_alloc mm/slub.c:3256 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3263 [inline]
 kmem_cache_alloc+0x267/0x3b0 mm/slub.c:3273
 kmem_cache_zalloc include/linux/slab.h:723 [inline]
 net_alloc net/core/net_namespace.c:403 [inline]
 copy_net_ns+0x125/0x760 net/core/net_namespace.c:458
 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:3181
 __do_sys_unshare kernel/fork.c:3252 [inline]
 __se_sys_unshare kernel/fork.c:3250 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3250
 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+0x63/0xcd

Last potentially related work creation:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
 __kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348
 insert_work+0x48/0x350 kernel/workqueue.c:1358
 __queue_work+0x625/0x1200 kernel/workqueue.c:1517
 call_timer_fn+0x1a0/0x6b0 kernel/time/timer.c:1474
 expire_timers kernel/time/timer.c:1514 [inline]
 __run_timers.part.0+0x4a3/0xa80 kernel/time/timer.c:1790
 __run_timers kernel/time/timer.c:1768 [inline]
 run_timer_softirq+0x152/0x1d0 kernel/time/timer.c:1805
 __do_softirq+0x1d0/0x9c8 kernel/softirq.c:571

Second to last potentially related work creation:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
 __kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348
 insert_work+0x48/0x350 kernel/workqueue.c:1358
 __queue_work+0x625/0x1200 kernel/workqueue.c:1517
 call_timer_fn+0x1a0/0x6b0 kernel/time/timer.c:1474
 expire_timers kernel/time/timer.c:1514 [inline]
 __run_timers.part.0+0x4a3/0xa80 kernel/time/timer.c:1790
 __run_timers kernel/time/timer.c:1768 [inline]
 run_timer_softirq+0x152/0x1d0 kernel/time/timer.c:1805
 __do_softirq+0x1d0/0x9c8 kernel/softirq.c:571

The buggy address belongs to the object at ffff888020d51c40
 which belongs to the cache net_namespace of size 6976
The buggy address is located 1861 bytes inside of
 6976-byte region [ffff888020d51c40, ffff888020d53780)

The buggy address belongs to the physical page:
page:ffffea0000835400 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888020d51c40 pfn:0x20d50
head:ffffea0000835400 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff88807da0d681
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffff8880119d5288 ffffea00007ebe08 ffff8880119d43c0
raw: ffff888020d51c40 0000000000040002 00000001ffffffff ffff88807da0d681
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3643, tgid 3643 (syz-executor.5), ts 137442519895, free_ts 128973404056
 prep_new_page mm/page_alloc.c:2532 [inline]
 get_page_from_freelist+0x109b/0x2ce0 mm/page_alloc.c:4283
 __alloc_pages+0x1c7/0x510 mm/page_alloc.c:5549
 alloc_pages+0x1a6/0x270 mm/mempolicy.c:2270
 alloc_slab_page mm/slub.c:1829 [inline]
 allocate_slab+0x27e/0x3d0 mm/slub.c:1974
 new_slab mm/slub.c:2034 [inline]
 ___slab_alloc+0x84f/0xe80 mm/slub.c:3036
 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3123
 slab_alloc_node mm/slub.c:3214 [inline]
 slab_alloc mm/slub.c:3256 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3263 [inline]
 kmem_cache_alloc+0x38c/0x3b0 mm/slub.c:3273
 kmem_cache_zalloc include/linux/slab.h:723 [inline]
 net_alloc net/core/net_namespace.c:403 [inline]
 copy_net_ns+0x125/0x760 net/core/net_namespace.c:458
 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:3181
 __do_sys_unshare kernel/fork.c:3252 [inline]
 __se_sys_unshare kernel/fork.c:3250 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3250
 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+0x63/0xcd
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1449 [inline]
 free_pcp_prepare+0x5e4/0xd20 mm/page_alloc.c:1499
 free_unref_page_prepare mm/page_alloc.c:3380 [inline]
 free_unref_page+0x19/0x4d0 mm/page_alloc.c:3476
 __unfreeze_partials+0x17c/0x1a0 mm/slub.c:2553
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:447
 kasan_slab_alloc include/linux/kasan.h:224 [inline]
 slab_post_alloc_hook mm/slab.h:727 [inline]
 slab_alloc_node mm/slub.c:3248 [inline]
 kmem_cache_alloc_node+0x2b1/0x3f0 mm/slub.c:3298
 __alloc_skb+0x210/0x2f0 net/core/skbuff.c:497
 alloc_skb_fclone include/linux/skbuff.h:1315 [inline]
 tcp_stream_alloc_skb+0x38/0x580 net/ipv4/tcp.c:861
 tcp_sendmsg_locked+0xc4b/0x2940 net/ipv4/tcp.c:1324
 tcp_sendmsg+0x2b/0x40 net/ipv4/tcp.c:1482
 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:825
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:734
 sock_write_iter+0x291/0x3d0 net/socket.c:1108
 call_write_iter include/linux/fs.h:2187 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x9e9/0xdd0 fs/read_write.c:584
 ksys_write+0x1e8/0x250 fs/read_write.c:637

Memory state around the buggy address:
 ffff888020d52280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888020d52300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888020d52380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff888020d52400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888020d52480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	01 00                	add    %eax,(%rax)
   2:	00 49 89             	add    %cl,-0x77(%rcx)
   5:	f8                   	clc
   6:	65 48 8b 14 25 80 6f 	mov    %gs:0x26f80,%rdx
   d:	02 00
   f:	a9 00 01 ff 00       	test   $0xff0100,%eax
  14:	74 0e                	je     0x24
  16:	85 f6                	test   %esi,%esi
  18:	74 59                	je     0x73
  1a:	8b 82 bc 15 00 00    	mov    0x15bc(%rdx),%eax
  20:	85 c0                	test   %eax,%eax
  22:	74 4f                	je     0x73
  24:	8b 82 98 15 00 00    	mov    0x1598(%rdx),%eax
* 2a:	83 f8 03             	cmp    $0x3,%eax <-- trapping instruction
  2d:	75 44                	jne    0x73
  2f:	48 8b 82 a0 15 00 00 	mov    0x15a0(%rdx),%rax
  36:	8b 92 9c 15 00 00    	mov    0x159c(%rdx),%edx
  3c:	48 8b 38             	mov    (%rax),%rdi
  3f:	48                   	rex.W