==================================================================
BUG: KASAN: use-after-free in tcp_retransmit_timer+0x6ee/0x2890 net/ipv4/tcp_timer.c:515
Read of size 8 at addr ffff88801bbd36d8 by task syz-executor.2/19622

CPU: 1 PID: 19622 Comm: syz-executor.2 Not tainted 5.15.110-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
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_retransmit_timer+0x6ee/0x2890 net/ipv4/tcp_timer.c:515
 tcp_write_timer_handler+0x1f7/0x9c0 net/ipv4/tcp_timer.c:626
 tcp_write_timer+0x12e/0x280 net/ipv4/tcp_timer.c:646
 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:636
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648
 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:memcg_slab_free_hook+0x139/0x200 mm/slab.h:360
Code: af e0 49 c1 ec 20 45 29 e6 0f b6 c3 83 f8 20 73 58 89 d9 41 d3 ee 45 01 e6 0f b6 c2 83 f8 20 73 6f 89 d1 41 d3 ee 4f 8b 24 f7 <4d> 85 e4 48 8b 1c 24 0f 84 29 ff ff ff 4b c7 04 f7 00 00 00 00 8b
RSP: 0018:ffffc9000320f8f0 EFLAGS: 00000246
RAX: 0000000000000008 RBX: 0000000000000801 RCX: 0000000000000008
RDX: 0000000000000008 RSI: 0000000000001f61 RDI: ffff888140006a00
RBP: 0000000000000000 R08: ffffffff81394b08 R09: fffffbfff1bc744e
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888022a61b00
R13: ffffea000072e840 R14: 0000000000000000 R15: ffff888073a57b00
 do_slab_free mm/slub.c:3432 [inline]
 ___cache_free+0x67/0x100 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
 do_sys_openat2+0xd2/0x500 fs/open.c:1205
 do_sys_open fs/open.c:1227 [inline]
 __do_sys_openat fs/open.c:1243 [inline]
 __se_sys_openat fs/open.c:1238 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1238
 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
RIP: 0033:0x7f7bafbea169
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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:00007f7bae15c168 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f7bafd09f80 RCX: 00007f7bafbea169
RDX: 00000000000026e1 RSI: 0000000020000300 RDI: ffffffffffffff9c
RBP: 00007f7bafc45ca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffec9c3ccef R14: 00007f7bae15c300 R15: 0000000000022000
 </TASK>

Allocated by task 11914:
 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:3094
 __do_sys_unshare kernel/fork.c:3168 [inline]
 __se_sys_unshare kernel/fork.c:3166 [inline]
 __x64_sys_unshare+0x34/0x40 kernel/fork.c:3166
 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 3587:
 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:2306
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2453
 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 ffff88801bbd3480
 which belongs to the cache net_namespace of size 6464
The buggy address is located 600 bytes inside of
 6464-byte region [ffff88801bbd3480, ffff88801bbd4dc0)
The buggy address belongs to the page:
page:ffffea00006ef400 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88801bbd0000 pfn:0x1bbd0
head:ffffea00006ef400 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff888019e58f41
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0001635208 ffffea0001d81e08 ffff888011dc63c0
raw: ffff88801bbd0000 0000000000040001 00000001ffffffff ffff888019e58f41
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 3802, ts 93832508485, free_ts 93720334975
 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
 copy_namespaces+0x365/0x3b0 kernel/nsproxy.c:178
 copy_process+0x1841/0x3ef0 kernel/fork.c:2201
 kernel_clone+0x210/0x960 kernel/fork.c:2601
 __do_sys_clone kernel/fork.c:2718 [inline]
 __se_sys_clone kernel/fork.c:2702 [inline]
 __x64_sys_clone+0x23f/0x290 kernel/fork.c:2702
 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
 kmem_cache_zalloc include/linux/slab.h:711 [inline]
 jbd2_alloc_handle include/linux/jbd2.h:1603 [inline]
 new_handle fs/jbd2/transaction.c:481 [inline]
 jbd2__journal_start+0x144/0x5c0 fs/jbd2/transaction.c:508
 __ext4_journal_start_sb+0x175/0x370 fs/ext4/ext4_jbd2.c:105
 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline]
 ext4_rmdir+0x41b/0xa80 fs/ext4/namei.c:3153
 vfs_rmdir+0x305/0x460 fs/namei.c:4078
 do_rmdir+0x362/0x670 fs/namei.c:4139
 __do_sys_unlinkat fs/namei.c:4319 [inline]
 __se_sys_unlinkat fs/namei.c:4313 [inline]
 __x64_sys_unlinkat+0xdc/0xf0 fs/namei.c:4313

Memory state around the buggy address:
 ffff88801bbd3580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88801bbd3600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88801bbd3680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                    ^
 ffff88801bbd3700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88801bbd3780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	af                   	scas   %es:(%rdi),%eax
   1:	e0 49                	loopne 0x4c
   3:	c1 ec 20             	shr    $0x20,%esp
   6:	45 29 e6             	sub    %r12d,%r14d
   9:	0f b6 c3             	movzbl %bl,%eax
   c:	83 f8 20             	cmp    $0x20,%eax
   f:	73 58                	jae    0x69
  11:	89 d9                	mov    %ebx,%ecx
  13:	41 d3 ee             	shr    %cl,%r14d
  16:	45 01 e6             	add    %r12d,%r14d
  19:	0f b6 c2             	movzbl %dl,%eax
  1c:	83 f8 20             	cmp    $0x20,%eax
  1f:	73 6f                	jae    0x90
  21:	89 d1                	mov    %edx,%ecx
  23:	41 d3 ee             	shr    %cl,%r14d
  26:	4f 8b 24 f7          	mov    (%r15,%r14,8),%r12
* 2a:	4d 85 e4             	test   %r12,%r12 <-- trapping instruction
  2d:	48 8b 1c 24          	mov    (%rsp),%rbx
  31:	0f 84 29 ff ff ff    	je     0xffffff60
  37:	4b c7 04 f7 00 00 00 	movq   $0x0,(%r15,%r14,8)
  3e:	00
  3f:	8b                   	.byte 0x8b