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BUG: KASAN: out-of-bounds in csd_lock_record+0xcb/0xe0 kernel/smp.c:118
Read of size 8 at addr ffffc90018107550 by task syz-executor.3/2446

CPU: 0 PID: 2446 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+0xcb/0xe0 kernel/smp.c:118
 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:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x4b/0x80 kernel/locking/spinlock.c:199
Code: c0 10 ff b4 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 31 48 83 3d ee 7a c8 01 00 74 25 fb 66 0f 1f 44 00 00 <bf> 01 00 00 00 e8 db 01 63 f9 65 8b 05 44 7a 15 78 85 c0 74 02 5d
RSP: 0018:ffffc900180a7168 EFLAGS: 00000286
RAX: 1ffffffff1369fe2 RBX: ffff888050b60000 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffffff87ec83ff
RBP: ffff8880ae635e00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff8880ae635e00
R13: ffff88809faa6280 R14: 0000000000000000 R15: 0000000000000001
 finish_lock_switch kernel/sched/core.c:3184 [inline]
 finish_task_switch+0x147/0x750 kernel/sched/core.c:3284
 context_switch kernel/sched/core.c:3448 [inline]
 __schedule+0x8bc/0x1e80 kernel/sched/core.c:4169
 preempt_schedule_irq+0xb0/0x150 kernel/sched/core.c:4427
 idtentry_exit_cond_resched arch/x86/entry/common.c:645 [inline]
 idtentry_exit_cond_rcu+0xc0/0xf0 arch/x86/entry/common.c:692
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:596
RIP: 0010:ipv6_conntrack_local+0x0/0x20 net/netfilter/nf_conntrack_proto.c:511
Code: 3e fb e9 53 ff ff ff 4c 89 f7 e8 7b 39 3e fb eb 93 e8 14 39 3e fb 48 8b 04 24 e9 79 fe ff ff e8 f6 38 3e fb e9 12 ff ff ff 90 <41> 54 49 89 d4 55 48 89 f5 e8 d2 9a fe fa 4c 89 e6 48 89 ef 5d 41
RSP: 0018:ffffc900180a7390 EFLAGS: 00000246
RAX: ffffffff86756c20 RBX: ffff888097013000 RCX: ffffc9000f689000
RDX: ffffc900180a74f0 RSI: ffff88808afc0900 RDI: 0000000000000000
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000007 R11: 0000000000000000 R12: ffff888097013020
R13: ffff88808afc0900 R14: ffffc900180a74f0 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]
 NF_HOOK include/linux/netfilter.h:305 [inline]
 rawv6_send_hdrinc net/ipv6/raw.c:687 [inline]
 rawv6_sendmsg+0x28a5/0x38f0 net/ipv6/raw.c:944
 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
 sock_no_sendpage+0xee/0x130 net/core/sock.c:2844
 kernel_sendpage net/socket.c:3642 [inline]
 sock_sendpage+0xe5/0x140 net/socket.c:945
 pipe_to_sendpage+0x2ad/0x380 fs/splice.c:448
 splice_from_pipe_feed fs/splice.c:502 [inline]
 __splice_from_pipe+0x3dc/0x830 fs/splice.c:626
 splice_from_pipe fs/splice.c:661 [inline]
 generic_splice_sendpage+0xd4/0x140 fs/splice.c:834
 do_splice_from fs/splice.c:846 [inline]
 direct_splice_actor+0x171/0x2f0 fs/splice.c:1016
 splice_direct_to_actor+0x38c/0x980 fs/splice.c:971
 do_splice_direct+0x1b3/0x280 fs/splice.c:1059
 do_sendfile+0x559/0xc30 fs/read_write.c:1521
 __do_sys_sendfile64 fs/read_write.c:1582 [inline]
 __se_sys_sendfile64 fs/read_write.c:1568 [inline]
 __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1568
 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:00007fed9e1f0c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00000000004fd720 RCX: 000000000045cb29
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000003
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 00008000fffffffe R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000902 R14: 00000000004cbe0a R15: 00007fed9e1f16d4


Memory state around the buggy address:
 ffffc90018107400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90018107480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc90018107500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                                    ^
 ffffc90018107580: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 00 00
 ffffc90018107600: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00
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