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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 ffffc900016f7558 by task syz-executor.4/15950

CPU: 0 PID: 15950 Comm: syz-executor.4 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:ip6table_security_hook+0x4a/0x70 net/ipv6/netfilter/ip6table_security.c:42
Code: 48 c1 ea 03 80 3c 02 00 75 38 48 b8 00 00 00 00 00 fc ff df 48 8b 5d 20 48 8d bb 40 0a 00 00 48 89 fa 48 c1 ea 03 80 3c 02 00 <75> 1d 48 8b 93 40 0a 00 00 48 89 ee 4c 89 e7 5b 5d 41 5c e9 4e 85
RSP: 0018:ffffc90001757500 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: ffff8880543d6140 RCX: ffffc90011b73000
RDX: 1ffff1100a87ad70 RSI: ffffffff86f8244f RDI: ffff8880543d6b80
RBP: ffffc900017575a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000007 R11: 0000000000000000 R12: ffff88808edb1480
R13: ffff88808edb1480 R14: ffffc900017575a0 R15: dffffc0000000000
 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline]
 nf_hook_slow+0xc5/0x1e0 net/netfilter/core.c:512
 nf_hook include/linux/netfilter.h:262 [inline]
 __ip6_local_out+0x419/0x890 net/ipv6/output_core.c:167
 ip6_local_out+0x26/0x1a0 net/ipv6/output_core.c:177
 ip6_send_skb+0xb7/0x340 net/ipv6/ip6_output.c:1865
 ip6_push_pending_frames+0xbd/0xe0 net/ipv6/ip6_output.c:1885
 rawv6_push_pending_frames net/ipv6/raw.c:613 [inline]
 rawv6_sendmsg+0x2add/0x38f0 net/ipv6/raw.c:956
 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:814
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:672
 ____sys_sendmsg+0x331/0x810 net/socket.c:2352
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2406
 __sys_sendmmsg+0x195/0x480 net/socket.c:2496
 __do_sys_sendmmsg net/socket.c:2525 [inline]
 __se_sys_sendmmsg net/socket.c:2522 [inline]
 __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2522
 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:00007f8a9d10ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00000000004fd760 RCX: 000000000045cb29
RDX: 0000000000000019 RSI: 0000000020000480 RDI: 0000000000000005
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000903 R14: 00000000004cbe13 R15: 00007f8a9d10f6d4


Memory state around the buggy address:
 ffffc900016f7400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc900016f7480: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
>ffffc900016f7500: 04 f2 04 f2 00 00 00 f2 00 00 00 f2 f2 f2 00 00
                                                       ^
 ffffc900016f7580: 00 00 00 00 00 00 00 f3 f3 f3 f3 f3 00 00 00 00
 ffffc900016f7600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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