==================================================================
BUG: KASAN: use-after-free in tcp_retransmit_timer+0x6ee/0x2890 net/ipv4/tcp_timer.c:515
Read of size 8 at addr ffff8880764b1c98 by task udevd/2963

CPU: 0 PID: 2963 Comm: udevd Not tainted 5.15.111-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023
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:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:193
Code: 1f 84 00 00 00 00 00 0f 1f 00 53 48 89 fb e8 17 00 00 00 48 8b 3d 08 c5 63 0c 48 89 de 5b e9 f7 83 48 00 cc cc cc cc cc cc cc <48> 8b 04 24 65 48 8b 0d d4 8b 82 7e 65 8b 15 d5 8b 82 7e f7 c2 00
RSP: 0018:ffffc90002bdfc08 EFLAGS: 00000246
RAX: ffffffff8c7c9e80 RBX: ffffffff8c7c9e80 RCX: ffffffff8c7c9e80
RDX: 0000000000000000 RSI: ffff888075a9e370 RDI: ffffc90002bdfde8
RBP: 0000000000000000 R08: ffffffff81faca1e R09: ffffed100eb53c7f
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc90002bdfe14
R13: ffffc90002bdfde0 R14: ffff888075a9e370 R15: dffffc0000000000
 mapped_kgid_fs include/linux/mnt_idmapping.h:113 [inline]
 i_gid_into_mnt include/linux/fs.h:1666 [inline]
 generic_fillattr+0x2ae/0x600 fs/stat.c:51
 kernfs_iop_getattr+0x23b/0x340 fs/kernfs/inode.c:191
 vfs_statx+0x18f/0x3b0 fs/stat.c:225
 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
RIP: 0033:0x7f71e2dfb5f4
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:00007ffd92ababd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 00007f71e2ed3460 RCX: 00007f71e2dfb5f4
RDX: 00007ffd92ababe0 RSI: 00007f71e2e98130 RDI: 000000000000000c
RBP: 0000559eda3adfd0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000001000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000003fff R14: 00007ffd92abb178 R15: 000000000000000a
 </TASK>

Allocated by task 26006:
 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 4092:
 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:2307
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2454
 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 ffff8880764b1a40
 which belongs to the cache net_namespace of size 6464
The buggy address is located 600 bytes inside of
 6464-byte region [ffff8880764b1a40, ffff8880764b3380)
The buggy address belongs to the page:
page:ffffea0001d92c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880764b3480 pfn:0x764b0
head:ffffea0001d92c00 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff888019d661c1
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0001680a08 ffffea00007f3008 ffff888011dc63c0
raw: ffff8880764b3480 0000000000040001 00000001ffffffff ffff888019d661c1
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 5389, ts 202675530491, free_ts 202632601695
 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]
 ext4_mb_new_blocks+0x633/0x4d50 fs/ext4/mballoc.c:5599
 ext4_alloc_branch fs/ext4/indirect.c:340 [inline]
 ext4_ind_map_blocks+0x10cd/0x29c0 fs/ext4/indirect.c:635
 ext4_map_blocks+0xa47/0x1e30 fs/ext4/inode.c:647
 ext4_iomap_alloc fs/ext4/inode.c:3406 [inline]
 ext4_iomap_begin+0x8d4/0xd70 fs/ext4/inode.c:3456
 iomap_iter+0x631/0xe30 fs/iomap/iter.c:74
 __iomap_dio_rw+0x13f4/0x1f40 fs/iomap/direct-io.c:585

Memory state around the buggy address:
 ffff8880764b1b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880764b1c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880764b1c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff8880764b1d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880764b1d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	84 00                	test   %al,(%rax)
   2:	00 00                	add    %al,(%rax)
   4:	00 00                	add    %al,(%rax)
   6:	0f 1f 00             	nopl   (%rax)
   9:	53                   	push   %rbx
   a:	48 89 fb             	mov    %rdi,%rbx
   d:	e8 17 00 00 00       	callq  0x29
  12:	48 8b 3d 08 c5 63 0c 	mov    0xc63c508(%rip),%rdi        # 0xc63c521
  19:	48 89 de             	mov    %rbx,%rsi
  1c:	5b                   	pop    %rbx
  1d:	e9 f7 83 48 00       	jmpq   0x488419
  22:	cc                   	int3
  23:	cc                   	int3
  24:	cc                   	int3
  25:	cc                   	int3
  26:	cc                   	int3
  27:	cc                   	int3
  28:	cc                   	int3
* 29:	48 8b 04 24          	mov    (%rsp),%rax <-- trapping instruction
  2d:	65 48 8b 0d d4 8b 82 	mov    %gs:0x7e828bd4(%rip),%rcx        # 0x7e828c09
  34:	7e
  35:	65 8b 15 d5 8b 82 7e 	mov    %gs:0x7e828bd5(%rip),%edx        # 0x7e828c11
  3c:	f7                   	.byte 0xf7
  3d:	c2                   	.byte 0xc2