================================================================== BUG: KASAN: stack-out-of-bounds in csd_lock_record+0xd2/0xe0 kernel/smp.c:119 Read of size 8 at addr ffffc90000d2f578 by task syz-executor.0/18748 CPU: 0 PID: 18748 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: __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 __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:ip_check_mc_rcu+0x3cc/0x659 net/ipv4/igmp.c:2706 Code: 03 01 e8 cc 61 9a fa e9 1a fd ff ff e8 0d d9 b3 fa 48 8d 7b 18 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 5f 02 00 00 48 8b 5b 18 e8 15 c3 29 01 31 ff 89 c5 89 c6 e8 RSP: 0018:ffffc90001d07320 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: ffff88809e402800 RCX: ffffc90001d69000 RDX: 1ffff11013c80503 RSI: ffffffff86c02df3 RDI: ffff88809e402818 RBP: 0000000000000001 R08: 0000000000000001 R09: ffff88803616eb10 R10: 0000000000000000 R11: 0000000000000000 R12: 00000000000000ee R13: 0000000000000000 R14: 00000000171414ac R15: 0000000000000002 __mkroute_output net/ipv4/route.c:2388 [inline] ip_route_output_key_hash_rcu+0x1869/0x26b0 net/ipv4/route.c:2669 ip_route_output_key_hash+0x1a4/0x2f0 net/ipv4/route.c:2495 __ip_route_output_key include/net/route.h:126 [inline] ip_route_output_flow+0x23/0xc0 net/ipv4/route.c:2758 ip_route_output_key include/net/route.h:142 [inline] ip_tunnel_xmit+0x74d/0x2ac3 net/ipv4/ip_tunnel.c:751 ipgre_xmit+0x651/0x9f0 net/ipv4/ip_gre.c:650 __netdev_start_xmit include/linux/netdevice.h:4613 [inline] netdev_start_xmit include/linux/netdevice.h:4627 [inline] xmit_one net/core/dev.c:3562 [inline] dev_hard_start_xmit+0x193/0x950 net/core/dev.c:3578 __dev_queue_xmit+0x2096/0x2d60 net/core/dev.c:4137 __bpf_tx_skb net/core/filter.c:2088 [inline] __bpf_redirect_no_mac net/core/filter.c:2113 [inline] __bpf_redirect+0x52e/0xc60 net/core/filter.c:2136 ____bpf_clone_redirect net/core/filter.c:2167 [inline] bpf_clone_redirect+0x2ae/0x420 net/core/filter.c:2139 bpf_prog_e2f29814702bf05a+0x5c/0x610 bpf_dispatcher_nop_func include/linux/bpf.h:567 [inline] bpf_test_run+0x3bb/0xc70 net/bpf/test_run.c:49 bpf_prog_test_run_skb+0x98b/0x14f0 net/bpf/test_run.c:459 bpf_prog_test_run kernel/bpf/syscall.c:2983 [inline] __do_sys_bpf+0x2117/0x4b10 kernel/bpf/syscall.c:4130 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:00007f4d47c4ac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00000000004dade0 RCX: 000000000045cb29 RDX: 0000000000000028 RSI: 0000000020000080 RDI: 000000000000000a RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000005d R14: 00000000004c32db R15: 00007f4d47c4b6d4 Memory state around the buggy address: ffffc90000d2f400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc90000d2f480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffffc90000d2f500: 00 00 00 00 f1 f1 f1 f1 00 00 00 00 f3 f3 f3 f3 ^ ffffc90000d2f580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc90000d2f600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================