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BUG: KASAN: stack-out-of-bounds in csd_lock_record+0xcb/0xe0 kernel/smp.c:118
Read of size 8 at addr ffffc90017037bf0 by task syz-executor.0/9987

CPU: 0 PID: 9987 Comm: syz-executor.0 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:xdp_rxq_info_unreg+0x25/0x180 net/core/xdp.c:138
Code: ff ff 0f 1f 00 41 54 55 53 48 89 fb e8 44 78 31 fb 48 8d 6b 0c 48 b8 00 00 00 00 00 fc ff df 48 89 ea 48 c1 ea 03 0f b6 14 02 <48> 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 11 01 00 00 44
RSP: 0018:ffffc90007f675f8 EFLAGS: 00000a07
RAX: dffffc0000000000 RBX: ffff888099bb9080 RCX: ffffc900019b9000
RDX: 0000000000000000 RSI: ffffffff86428ebc RDI: ffff888099bb9080
RBP: ffff888099bb908c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888099bb9000
R13: 0000000000000001 R14: ffffed10094e906b R15: 0000000000000001
 netif_free_rx_queues net/core/dev.c:9345 [inline]
 free_netdev+0x11f/0x480 net/core/dev.c:10038
 netdev_run_todo+0x88e/0xac0 net/core/dev.c:9797
 rtnl_unlock net/core/rtnetlink.c:112 [inline]
 rtnetlink_rcv_msg+0x45b/0xad0 net/core/rtnetlink.c:5461
 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2469
 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1329
 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1918
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:672
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2352
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2406
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2439
 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:00007fec3fd42c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000502760 RCX: 000000000045cb29
RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000004
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000a43 R14: 00000000004cd2a1 R15: 00007fec3fd436d4


Memory state around the buggy address:
 ffffc90017037a80: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
 ffffc90017037b00: 00 00 00 00 00 00 00 00 00 00 00 f3 f3 f3 f3 f3
>ffffc90017037b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1
                                                             ^
 ffffc90017037c00: f1 00 00 00 f3 f3 f3 f3 f3 00 00 00 00 00 00 00
 ffffc90017037c80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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