audit: type=1804 audit(1546505619.770:263): pid=1442 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor3" name="/root/syzkaller-testdir524106829/syzkaller.2nCXlX/872/memory.events" dev="sda1" ino=16728 res=1 BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 kobject: 'loop2' (00000000ce663b24): kobject_uevent_env #PF error: [INSTR] PGD a5340067 P4D a5340067 PUD 8b44d067 PMD 0 Oops: 0010 [#1] PREEMPT SMP KASAN CPU: 0 PID: 1396 Comm: syz-executor4 Not tainted 4.20.0+ #2 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010: (null) kobject: 'loop2' (00000000ce663b24): fill_kobj_path: path = '/devices/virtual/block/loop2' Code: Bad RIP value. RSP: 0018:ffff8880ae607b08 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff86232477 RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff88809edd6758 RBP: ffff8880ae607e60 R08: ffff88809b9d6100 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 audit: type=1804 audit(1546505619.840:264): pid=1439 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor0" name="/root/syzkaller-testdir883732523/syzkaller.zyHxEk/27/memory.events" dev="sda1" ino=16705 res=1 R13: dffffc0000000000 R14: ffff8880ae607e38 R15: ffff88809edd6758 FS: 00007f2feb924700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000000962ed000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000020000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: __do_softirq+0x30b/0xb11 kernel/softirq.c:292 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1027 do_softirq.part.0+0x11a/0x170 kernel/softirq.c:337 do_softirq kernel/softirq.c:329 [inline] __local_bh_enable_ip+0x211/0x270 kernel/softirq.c:189 local_bh_enable include/linux/bottom_half.h:32 [inline] tun_get_user+0x237e/0x4150 drivers/net/tun.c:1987 kobject: 'tx-1' (00000000d45d3588): kobject_add_internal: parent: 'queues', set: 'queues' audit: type=1804 audit(1546505619.840:265): pid=1446 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor0" name="/root/syzkaller-testdir883732523/syzkaller.zyHxEk/27/memory.events" dev="sda1" ino=16705 res=1 kobject: 'tx-1' (00000000d45d3588): kobject_uevent_env kobject: 'tx-1' (00000000d45d3588): fill_kobj_path: path = '/devices/virtual/net/nr0/queues/tx-1' tun_chr_write_iter+0xbd/0x160 drivers/net/tun.c:2017 call_write_iter include/linux/fs.h:1857 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x6e5/0xa80 fs/read_write.c:487 kobject: 'rx-1' (0000000031effe32): kobject_add_internal: parent: 'queues', set: 'queues' vfs_write+0x20c/0x560 fs/read_write.c:549 ksys_write+0x105/0x260 fs/read_write.c:598 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457ec9 Code: 6d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f2feb923c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457ec9 RDX: 0000000000000012 RSI: 0000000020000000 RDI: 0000000000000012 RBP: 000000000073c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2feb9246d4 R13: 00000000004c6fc2 R14: 00000000004dc520 R15: 00000000ffffffff Modules linked in: CR2: 0000000000000000 ---[ end trace 9abf7c9d0b9414ce ]--- RIP: 0010: (null) Code: Bad RIP value. RSP: 0018:ffff8880ae607b08 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff86232477 RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff88809edd6758 RBP: ffff8880ae607e60 R08: ffff88809b9d6100 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 R13: dffffc0000000000 R14: ffff8880ae607e38 R15: ffff88809edd6758 FS: 00007f2feb924700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000000962ed000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000020000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600