==================================================================
BUG: KASAN: use-after-free in tcp_probe_timer net/ipv4/tcp_timer.c:384 [inline]
BUG: KASAN: use-after-free in tcp_write_timer_handler+0x882/0x9c0 net/ipv4/tcp_timer.c:648
Read of size 1 at addr ffff888019e620cd by task syz-executor.3/12445

CPU: 1 PID: 12445 Comm: syz-executor.3 Not tainted 5.15.152-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description+0x63/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
 tcp_probe_timer net/ipv4/tcp_timer.c:384 [inline]
 tcp_write_timer_handler+0x882/0x9c0 net/ipv4/tcp_timer.c:648
 tcp_write_timer+0x12e/0x280 net/ipv4/tcp_timer.c:664
 call_timer_fn+0x16d/0x560 kernel/time/timer.c:1421
 expire_timers kernel/time/timer.c:1466 [inline]
 __run_timers+0x67c/0x890 kernel/time/timer.c:1737
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1750
 __do_softirq+0x3b3/0x93a kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x155/0x240 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:58 [inline]
RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:347 [inline]
RIP: 0010:deref_stack_reg+0x5f/0x110 arch/x86/kernel/unwind_orc.c:357
Code: 8b 6b 08 48 8d 7b 10 48 89 f8 48 c1 e8 03 42 80 3c 20 00 74 05 e8 d1 6e 91 00 48 8b 6b 10 48 89 d8 48 c1 e8 03 42 0f b6 04 20 <84> c0 0f 85 80 00 00 00 83 3b 00 74 18 4d 39 fd 77 13 4c 39 fd 76
RSP: 0000:ffffc900045df590 EFLAGS: 00000a02
RAX: 0000000000000000 RBX: ffffc900045df680 RCX: 0000000000000000
RDX: ffffc900045df6c0 RSI: ffffc900045dfa28 RDI: ffffc900045df690
RBP: ffffc900045e0000 R08: ffffc900045dfa28 R09: ffffc900045df6d0
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffffc900045d8000 R14: ffffc900045df6c0 R15: ffffc900045dfa28
 unwind_next_frame+0x12f1/0x1fa0
 arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x8e/0xc0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x53/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3220 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0xf3/0x280 mm/slub.c:3233
 ptlock_alloc+0x1c/0x60 mm/memory.c:5523
 ptlock_init include/linux/mm.h:2230 [inline]
 pgtable_pte_page_ctor include/linux/mm.h:2257 [inline]
 __pte_alloc_one include/asm-generic/pgalloc.h:66 [inline]
 pte_alloc_one+0xd1/0x360 arch/x86/mm/pgtable.c:33
 __do_fault+0xd6/0x340 mm/memory.c:3892
 do_shared_fault mm/memory.c:4288 [inline]
 do_fault mm/memory.c:4366 [inline]
 handle_pte_fault mm/memory.c:4621 [inline]
 __handle_mm_fault mm/memory.c:4756 [inline]
 handle_mm_fault+0x275d/0x5950 mm/memory.c:4854
 do_user_addr_fault arch/x86/mm/fault.c:1397 [inline]
 handle_page_fault arch/x86/mm/fault.c:1485 [inline]
 exc_page_fault+0x271/0x740 arch/x86/mm/fault.c:1541
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:568
RIP: 0033:0x7f45b8ea7266
Code: 1f 44 00 00 48 8b 0d 91 d4 ca 00 4c 63 05 7a d4 ca 00 48 8b 05 7b d4 ca 00 49 01 c8 48 39 c8 72 13 4c 39 c0 73 0e 48 8d 50 04 <89> 38 48 89 15 61 d4 ca 00 c3 52 48 8d 35 c3 0e 0a 00 48 89 c2 48
RSP: 002b:00007fff3946bd48 EFLAGS: 00010287
RAX: 0000001b31b20000 RBX: 0000000000000003 RCX: 0000001b31b20000
RDX: 0000001b31b20004 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000001b32120000 R09: 0000000000040000
R10: 0000000000000011 R11: 0000000000000293 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000001
 </TASK>

Allocated by task 7966:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x8e/0xc0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x53/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3220 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0xf3/0x280 mm/slub.c:3233
 kmem_cache_zalloc include/linux/slab.h:711 [inline]
 net_alloc net/core/net_namespace.c:405 [inline]
 copy_net_ns+0x143/0x5d0 net/core/net_namespace.c:460
 create_new_namespaces+0x425/0x7a0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x11e/0x170 kernel/nsproxy.c:226
 ksys_unshare+0x580/0xb20 kernel/fork.c:3101
 __do_sys_unshare kernel/fork.c:3175 [inline]
 __se_sys_unshare kernel/fork.c:3173 [inline]
 __x64_sys_unshare+0x34/0x40 kernel/fork.c:3173
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Freed by task 6688:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x80 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1705 [inline]
 slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731
 slab_free mm/slub.c:3499 [inline]
 kmem_cache_free+0x91/0x1f0 mm/slub.c:3515
 net_free net/core/net_namespace.c:434 [inline]
 cleanup_net+0xab5/0xb60 net/core/net_namespace.c:617
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

The buggy address belongs to the object at ffff888019e61a40
 which belongs to the cache net_namespace of size 6464
The buggy address is located 1677 bytes inside of
 6464-byte region [ffff888019e61a40, ffff888019e63380)
The buggy address belongs to the page:
page:ffffea0000679800 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888019e60000 pfn:0x19e60
head:ffffea0000679800 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff888020d2cb41
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888011dea3c0
raw: ffff888019e60000 0000000080040003 00000001ffffffff ffff888020d2cb41
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 7028, ts 192219390822, free_ts 192201547511
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159
 __alloc_pages+0x272/0x700 mm/page_alloc.c:5421
 alloc_slab_page mm/slub.c:1775 [inline]
 allocate_slab mm/slub.c:1912 [inline]
 new_slab+0xbb/0x4b0 mm/slub.c:1975
 ___slab_alloc+0x6f6/0xe10 mm/slub.c:3008
 __slab_alloc mm/slub.c:3095 [inline]
 slab_alloc_node mm/slub.c:3186 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0x18e/0x280 mm/slub.c:3233
 kmem_cache_zalloc include/linux/slab.h:711 [inline]
 net_alloc net/core/net_namespace.c:405 [inline]
 copy_net_ns+0x143/0x5d0 net/core/net_namespace.c:460
 create_new_namespaces+0x425/0x7a0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x11e/0x170 kernel/nsproxy.c:226
 ksys_unshare+0x580/0xb20 kernel/fork.c:3101
 __do_sys_unshare kernel/fork.c:3175 [inline]
 __se_sys_unshare kernel/fork.c:3173 [inline]
 __x64_sys_unshare+0x34/0x40 kernel/fork.c:3173
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317
 free_unref_page+0x95/0x2d0 mm/page_alloc.c:3396
 free_slab mm/slub.c:2015 [inline]
 discard_slab mm/slub.c:2021 [inline]
 __unfreeze_partials+0x1b7/0x210 mm/slub.c:2507
 put_cpu_partial+0x132/0x1a0 mm/slub.c:2587
 do_slab_free mm/slub.c:3487 [inline]
 ___cache_free+0xe3/0x100 mm/slub.c:3506
 qlist_free_all+0x36/0x90 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x162/0x180 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xc0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x53/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3220 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0xf3/0x280 mm/slub.c:3233
 getname_flags+0xb8/0x4e0 fs/namei.c:138
 user_path_at_empty+0x2a/0x180 fs/namei.c:2882
 user_path_at include/linux/namei.h:57 [inline]
 vfs_statx+0x106/0x3b0 fs/stat.c:221
 vfs_fstatat fs/stat.c:243 [inline]
 __do_sys_newfstatat fs/stat.c:411 [inline]
 __se_sys_newfstatat fs/stat.c:405 [inline]
 __x64_sys_newfstatat+0x12c/0x1b0 fs/stat.c:405
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Memory state around the buggy address:
 ffff888019e61f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888019e62000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888019e62080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                              ^
 ffff888019e62100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888019e62180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	8b 6b 08             	mov    0x8(%rbx),%ebp
   3:	48 8d 7b 10          	lea    0x10(%rbx),%rdi
   7:	48 89 f8             	mov    %rdi,%rax
   a:	48 c1 e8 03          	shr    $0x3,%rax
   e:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1)
  13:	74 05                	je     0x1a
  15:	e8 d1 6e 91 00       	call   0x916eeb
  1a:	48 8b 6b 10          	mov    0x10(%rbx),%rbp
  1e:	48 89 d8             	mov    %rbx,%rax
  21:	48 c1 e8 03          	shr    $0x3,%rax
  25:	42 0f b6 04 20       	movzbl (%rax,%r12,1),%eax
* 2a:	84 c0                	test   %al,%al <-- trapping instruction
  2c:	0f 85 80 00 00 00    	jne    0xb2
  32:	83 3b 00             	cmpl   $0x0,(%rbx)
  35:	74 18                	je     0x4f
  37:	4d 39 fd             	cmp    %r15,%r13
  3a:	77 13                	ja     0x4f
  3c:	4c 39 fd             	cmp    %r15,%rbp
  3f:	76                   	.byte 0x76