audit: type=1804 audit(1602367115.658:52): pid=17038 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op=invalid_pcr cause=ToMToU comm="syz-executor.2" name="/root/syzkaller-testdir620964326/syzkaller.fvOKnb/273/bus/file0" dev="overlay" ino=16782 res=1 overlayfs: failed to resolve './file0': -2 INFO: task syz-executor.0:9387 blocked for more than 140 seconds. Not tainted 4.19.150-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29232 9387 6506 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x8e5/0x22e0 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 request_wait_answer+0x3dc/0x750 fs/fuse/dev.c:485 __fuse_request_send+0x123/0x1d0 fs/fuse/dev.c:505 fuse_simple_request+0x2d2/0x6f0 fs/fuse/dev.c:576 fuse_do_getattr+0x230/0xc40 fs/fuse/dir.c:927 fuse_update_get_attr fs/fuse/dir.c:960 [inline] fuse_getattr+0x2c1/0x380 fs/fuse/dir.c:1838 vfs_getattr_nosec+0xff/0x160 fs/stat.c:79 vfs_getattr fs/stat.c:116 [inline] vfs_statx+0x15a/0x210 fs/stat.c:189 vfs_stat include/linux/fs.h:3133 [inline] __do_sys_newstat fs/stat.c:337 [inline] __se_sys_newstat+0x96/0x120 fs/stat.c:333 do_syscall_64+0xf9/0x670 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45de59 Code: 0d b4 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 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f4363d61c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000035100 RCX: 000000000045de59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200004c0 RBP: 000000000118bf58 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c R13: 00007ffe9d43d38f R14: 00007f4363d629c0 R15: 000000000118bf2c Showing all locks held in the system: 2 locks held by kworker/u4:0/7: #0: 00000000ed64b30a (&rq->lock){-.-.}, at: idle_balance kernel/sched/fair.c:9701 [inline] #0: 00000000ed64b30a (&rq->lock){-.-.}, at: pick_next_task_fair+0x5ab/0x1630 kernel/sched/fair.c:6840 #1: 000000007a72d758 (rcu_read_lock){....}, at: cpu_of kernel/sched/sched.h:927 [inline] #1: 000000007a72d758 (rcu_read_lock){....}, at: __update_idle_core+0x39/0x530 kernel/sched/fair.c:6057 1 lock held by khungtaskd/1095: #0: 000000007a72d758 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x291 kernel/locking/lockdep.c:4440 1 lock held by in:imklog/6186: 2 locks held by agetty/6408: #0: 000000008c8b5a16 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000b9f63e58 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x18c0 drivers/tty/n_tty.c:2154 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1095 Comm: khungtaskd Not tainted 4.19.150-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+0x22c/0x33e lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x18/0x3d lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1eb lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0xa62/0x1020 kernel/hung_task.c:287 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3713 Comm: systemd-journal Not tainted 4.19.150-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:152 [inline] RIP: 0010:unwind_next_frame+0x2f0/0x2430 arch/x86/kernel/unwind_orc.c:429 Code: 24 30 48 8b 44 24 28 44 8b 5c 24 20 48 8b 4c 24 18 8b 14 b5 84 7f 1e 8c 44 89 df 48 8d 34 7f 48 8d b4 36 bc 91 9b 8b 83 c2 01 <48> 81 fe 84 7f 1e 8c 0f 83 91 11 00 00 41 89 d0 4f 8d 04 40 4f 8d RSP: 0018:ffff8880940378f8 EFLAGS: 00000202 RAX: 000000000000335c RBX: 1ffff11012806f27 RCX: ffffffff81335ca1 RDX: 000000000000c77c RSI: ffffffff8ba03e9e RDI: 000000000000c77b RBP: 0000000000000001 R08: 0000000000000000 R09: ffff888094037ab0 R10: ffff888094037ae7 R11: 000000000000c77b R12: ffff888094037ad0 R13: ffff888094037abd R14: ffff888094037ad8 R15: ffff888094037a88 FS: 00007f8f84b048c0(0000) GS:ffff8880ae300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8f81f7c000 CR3: 00000000945c9000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __unwind_start+0x5e5/0x970 arch/x86/kernel/unwind_orc.c:674 unwind_start arch/x86/include/asm/unwind.h:60 [inline] __save_stack_trace+0x5c/0x100 arch/x86/kernel/stacktrace.c:43 save_stack mm/kasan/kasan.c:448 [inline] set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:553 slab_post_alloc_hook mm/slab.h:445 [inline] slab_alloc mm/slab.c:3397 [inline] __do_kmalloc mm/slab.c:3725 [inline] __kmalloc_track_caller+0x13f/0x4e0 mm/slab.c:3742 kmemdup+0x23/0x50 mm/util.c:118 kmemdup include/linux/string.h:446 [inline] selinux_cred_prepare+0x44/0xa0 security/selinux/hooks.c:3994 security_prepare_creds+0x50/0xb0 security/security.c:1014 prepare_creds+0x32d/0x510 kernel/cred.c:282 do_faccessat+0x94/0x7f0 fs/open.c:359 do_syscall_64+0xf9/0x670 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f8f83dc09c7 Code: 83 c4 08 48 3d 01 f0 ff ff 73 01 c3 48 8b 0d c8 d4 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 b8 15 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 d4 2b 00 f7 d8 64 89 01 48 RSP: 002b:00007ffc1265f9c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 00007ffc126628e0 RCX: 00007f8f83dc09c7 RDX: 00007f8f84831a00 RSI: 0000000000000000 RDI: 000055abb6aab9a3 RBP: 00007ffc1265fa00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ffc126628e0 R15: 00007ffc1265fef0