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BUG: KASAN: use-after-free in tcp_retransmit_timer+0x6ee/0x2890 net/ipv4/tcp_timer.c:515
Read of size 8 at addr ffff8880754236d8 by task syz-executor.5/8742

CPU: 1 PID: 8742 Comm: syz-executor.5 Not tainted 5.15.116-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
Call Trace:
 <TASK>
 __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+0x43/0xb0 arch/x86/kernel/apic/apic.c:1096
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0033:0x7f3d3e015278
Code: 49 8b 50 f8 48 89 ee 4c 89 e3 4c 89 c0 0f 1f 44 00 00 49 89 dd 48 39 cf 72 2f 48 83 e8 08 48 39 d1 73 14 0f 1f 80 00 00 00 00 <48> 8b 50 f8 48 83 e8 08 48 39 ca 77 f3 48 39 c3 73 3e 48 89 13 48
RSP: 002b:00007ffdcc25ede0 EFLAGS: 00000206
RAX: 00007f3d3d867180 RBX: 00007f3d3d7e4030 RCX: ffffffff81a65dd1
RDX: ffffffff83ebaa76 RSI: 00007f3d3d7e4038 RDI: ffffffff821cb724
RBP: 00007f3d3d7dc018 R08: 00007f3d3d87d870 R09: 0000000081a6529c
R10: 0000000000000000 R11: 0000000000000000 R12: 00007f3d3d7dc010
R13: 00007f3d3d7e4030 R14: 00007f3d3d7dc008 R15: 000000000000001f
 </TASK>

Allocated by task 3542:
 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 3918:
 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 ffff888075423480
 which belongs to the cache net_namespace of size 6464
The buggy address is located 600 bytes inside of
 6464-byte region [ffff888075423480, ffff888075424dc0)
The buggy address belongs to the page:
page:ffffea0001d50800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x75420
head:ffffea0001d50800 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea000145d200 0000000200000002 ffff888011dc63c0
raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000
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 3525, ts 72374241415, free_ts 72338767427
 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: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
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]
 __kmalloc+0x120/0x300 mm/slub.c:4403
 kmalloc include/linux/slab.h:596 [inline]
 tomoyo_add_entry security/tomoyo/common.c:2031 [inline]
 tomoyo_supervisor+0xe67/0x12c0 security/tomoyo/common.c:2103
 tomoyo_audit_path_log security/tomoyo/file.c:168 [inline]
 tomoyo_path_permission+0x243/0x360 security/tomoyo/file.c:587
 tomoyo_check_open_permission+0x350/0x490 security/tomoyo/file.c:780
 security_file_open+0x5f/0xa0 security/security.c:1650
 do_dentry_open+0x315/0xfb0 fs/open.c:813
 do_open fs/namei.c:3538 [inline]
 path_openat+0x2702/0x2f20 fs/namei.c:3672

Memory state around the buggy address:
 ffff888075423580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888075423600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888075423680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                    ^
 ffff888075423700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888075423780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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