INFO: trying to register non-static key. the code is fine but needs lockdep annotation. turning off the locking correctness validator. CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.0.0+ #97 kobject: 'loop1' (000000008d00c1b6): kobject_uevent_env 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+0x172/0x1f0 lib/dump_stack.c:113 assign_lock_key kernel/locking/lockdep.c:731 [inline] register_lock_class+0x1bdc/0x1bf0 kernel/locking/lockdep.c:757 kobject: 'loop1' (000000008d00c1b6): fill_kobj_path: path = '/devices/virtual/block/loop1' __lock_acquire+0x11f/0x4700 kernel/locking/lockdep.c:3224 audit: type=1804 audit(1552140899.339:146): pid=30659 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.1" name="/root/syzkaller-testdir100370713/syzkaller.IBWukE/758/memory.events" dev="sda1" ino=16658 res=1 audit: type=1804 audit(1552140899.339:147): pid=30659 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.1" name="/root/syzkaller-testdir100370713/syzkaller.IBWukE/758/memory.events" dev="sda1" ino=16658 res=1 lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:3841 __raw_spin_trylock include/linux/spinlock_api_smp.h:90 [inline] _raw_spin_trylock+0x62/0x80 kernel/locking/spinlock.c:128 spin_trylock include/linux/spinlock.h:339 [inline] icmp_xmit_lock net/ipv4/icmp.c:219 [inline] __icmp_send+0x553/0x1400 net/ipv4/icmp.c:666 icmp_send include/net/icmp.h:47 [inline] __udp4_lib_rcv+0x1fb6/0x2c50 net/ipv4/udp.c:2323 device sit0 entered promiscuous mode udp_rcv+0x22/0x30 net/ipv4/udp.c:2482 ip_protocol_deliver_rcu+0x60/0x8f0 net/ipv4/ip_input.c:208 ip_local_deliver_finish+0x23b/0x390 net/ipv4/ip_input.c:234 audit: type=1804 audit(1552140899.639:148): pid=30687 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.1" name="/root/syzkaller-testdir100370713/syzkaller.IBWukE/759/memory.events" dev="sda1" ino=16706 res=1 NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] ip_local_deliver+0x1e9/0x520 net/ipv4/ip_input.c:255 dst_input include/net/dst.h:450 [inline] ip_rcv_finish+0x1e1/0x300 net/ipv4/ip_input.c:414 NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] ip_rcv+0xe8/0x3f0 net/ipv4/ip_input.c:524 __netif_receive_skb_one_core+0x115/0x1a0 net/core/dev.c:4973 __netif_receive_skb+0x2c/0x1c0 net/core/dev.c:5083 process_backlog+0x206/0x750 net/core/dev.c:5923 napi_poll net/core/dev.c:6346 [inline] net_rx_action+0x4fa/0x1070 net/core/dev.c:6412 __do_softirq+0x266/0x95a kernel/softirq.c:292 run_ksoftirqd kernel/softirq.c:654 [inline] run_ksoftirqd+0x8e/0x110 kernel/softirq.c:646 smpboot_thread_fn+0x6ab/0xa10 kernel/smpboot.c:164 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.0.0+ #97 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__ip_append_data.isra.0+0x2e6/0x2dd0 net/ipv4/ip_output.c:898 Code: c7 85 cc fe ff ff 00 00 00 00 0f 85 28 13 00 00 e8 0f a8 99 fb 48 8b 95 38 ff ff ff 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 73 28 00 00 48 8b 85 38 ff ff ff 48 8b 18 48 b8 RSP: 0018:ffff8880aa26f2a0 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff85d60de1 RDX: 0000000000000000 RSI: ffffffff85d60e61 RDI: 0000000000000001 RBP: ffff8880aa26f410 R08: ffff8880aa25c240 R09: ffffffff85e664d0 R10: ffff8880aa26f580 R11: ffff8880ae82de7b R12: ffff88806afd50f0 R13: ffff88806afd5590 R14: 0000000000000001 R15: dead4ead00000000 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc90fda020 CR3: 000000009f83a000 CR4: 00000000001406f0 Call Trace: ip_append_data.part.0+0xf2/0x170 net/ipv4/ip_output.c:1220 ip_append_data+0x6e/0x90 net/ipv4/ip_output.c:1209 icmp_push_reply+0x189/0x510 net/ipv4/icmp.c:375 __icmp_send+0xaa1/0x1400 net/ipv4/icmp.c:737 icmp_send include/net/icmp.h:47 [inline] __udp4_lib_rcv+0x1fb6/0x2c50 net/ipv4/udp.c:2323 udp_rcv+0x22/0x30 net/ipv4/udp.c:2482 ip_protocol_deliver_rcu+0x60/0x8f0 net/ipv4/ip_input.c:208 ip_local_deliver_finish+0x23b/0x390 net/ipv4/ip_input.c:234 NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] ip_local_deliver+0x1e9/0x520 net/ipv4/ip_input.c:255 dst_input include/net/dst.h:450 [inline] ip_rcv_finish+0x1e1/0x300 net/ipv4/ip_input.c:414 NF_HOOK include/linux/netfilter.h:289 [inline] NF_HOOK include/linux/netfilter.h:283 [inline] ip_rcv+0xe8/0x3f0 net/ipv4/ip_input.c:524 __netif_receive_skb_one_core+0x115/0x1a0 net/core/dev.c:4973 __netif_receive_skb+0x2c/0x1c0 net/core/dev.c:5083 process_backlog+0x206/0x750 net/core/dev.c:5923 napi_poll net/core/dev.c:6346 [inline] net_rx_action+0x4fa/0x1070 net/core/dev.c:6412 __do_softirq+0x266/0x95a kernel/softirq.c:292 run_ksoftirqd kernel/softirq.c:654 [inline] run_ksoftirqd+0x8e/0x110 kernel/softirq.c:646 smpboot_thread_fn+0x6ab/0xa10 kernel/smpboot.c:164 kthread+0x357/0x430 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 Modules linked in: audit: type=1804 audit(1552140900.259:149): pid=30684 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.1" name="/root/syzkaller-testdir100370713/syzkaller.IBWukE/759/memory.events" dev="sda1" ino=16706 res=1 ---[ end trace 05de7a7eac6fac43 ]--- RIP: 0010:__ip_append_data.isra.0+0x2e6/0x2dd0 net/ipv4/ip_output.c:898 Code: c7 85 cc fe ff ff 00 00 00 00 0f 85 28 13 00 00 e8 0f a8 99 fb 48 8b 95 38 ff ff ff 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 73 28 00 00 48 8b 85 38 ff ff ff 48 8b 18 48 b8 RSP: 0018:ffff8880aa26f2a0 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff85d60de1 RDX: 0000000000000000 RSI: ffffffff85d60e61 RDI: 0000000000000001 RBP: ffff8880aa26f410 R08: ffff8880aa25c240 R09: ffffffff85e664d0 R10: ffff8880aa26f580 R11: ffff8880ae82de7b R12: ffff88806afd50f0 R13: ffff88806afd5590 R14: 0000000000000001 R15: dead4ead00000000 FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc90fda020 CR3: 000000009f83a000 CR4: 00000000001406f0