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BUG: KASAN: stack-out-of-bounds in csd_lock_record+0xd2/0xe0 kernel/smp.c:119
Read of size 8 at addr ffffc900046776f8 by task syz-executor.3/9190

CPU: 1 PID: 9190 Comm: syz-executor.3 Not tainted 5.8.0-rc3-next-20200703-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x18f/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0x5/0x436 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 csd_lock_record+0xd2/0xe0 kernel/smp.c:119
 flush_smp_call_function_queue+0x285/0x730 kernel/smp.c:391
 __sysvec_call_function_single+0x98/0x490 arch/x86/kernel/smp.c:248
 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline]
 sysvec_call_function_single+0xe0/0x120 arch/x86/kernel/smp.c:243
 asm_sysvec_call_function_single+0x12/0x20 arch/x86/include/asm/idtentry.h:604
RIP: 0010:is_a_nulls include/linux/list_nulls.h:45 [inline]
RIP: 0010:inet_twsk_purge+0x15f/0x7b0 net/ipv4/inet_timewait_sock.c:270
Code: 89 de e8 b4 74 c6 fa 84 db 0f 84 cf 04 00 00 e8 67 78 c6 fa 48 8b 44 24 18 80 38 00 0f 85 ad 04 00 00 48 8b 44 24 10 48 8b 18 <eb> 1a e8 4a 78 c6 fa 48 89 d8 48 c1 e8 03 42 80 3c 38 00 0f 85 a1
RSP: 0018:ffffc90004af78c0 EFLAGS: 00000246
RAX: ffff888214486300 RBX: 00000000000218c1 RCX: ffffc90010477000
RDX: 0000000000040000 RSI: ffffffff86ad8e99 RDI: 0000000000000001
RBP: 0000000000010c60 R08: 0000000000000000 R09: ffffffff8c5a7a27
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff8a978480
R13: ffffc90004af7a28 R14: 000000000000000a R15: dffffc0000000000
 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:189
 setup_net+0x502/0x850 net/core/net_namespace.c:364
 copy_net_ns+0x2cf/0x5e0 net/core/net_namespace.c:482
 create_new_namespaces+0x3f6/0xb10 kernel/nsproxy.c:110
 copy_namespaces+0x385/0x470 kernel/nsproxy.c:179
 copy_process+0x2921/0x6b90 kernel/fork.c:2083
 _do_fork+0x12c/0xa70 kernel/fork.c:2425
 __do_sys_clone+0xef/0x150 kernel/fork.c:2581
 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:367
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45cb29
Code: Bad RIP value.
RSP: 002b:00007fa16ee25c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00000000004db5a0 RCX: 000000000045cb29
RDX: 9999999999999999 RSI: 0000000000000000 RDI: 0000000050000103
RBP: 000000000078c2c0 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000007c R14: 00000000004c34ba R15: 00007fa16ee266d4


Memory state around the buggy address:
 ffffc90004677580: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
 ffffc90004677600: 00 00 00 00 00 00 00 00 00 00 00 f3 f3 f3 f3 f3
>ffffc90004677680: 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1
                                                                ^
 ffffc90004677700: f1 00 00 00 f3 f3 f3 f3 f3 00 00 00 00 00 00 00
 ffffc90004677780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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