INFO: task syz-executor.1:12368 blocked for more than 143 seconds. Not tainted 5.12.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:27224 pid:12368 ppid: 8422 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4324 [inline] __schedule+0x90c/0x21a0 kernel/sched/core.c:5075 schedule+0xcf/0x270 kernel/sched/core.c:5154 rwsem_down_write_slowpath+0x7e5/0x1200 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1407 inode_lock include/linux/fs.h:775 [inline] lock_mount+0x8a/0x2e0 fs/namespace.c:2216 do_new_mount_fc fs/namespace.c:2846 [inline] do_new_mount fs/namespace.c:2905 [inline] path_mount+0x14d6/0x1f90 fs/namespace.c:3233 do_mount fs/namespace.c:3246 [inline] __do_sys_mount fs/namespace.c:3454 [inline] __se_sys_mount fs/namespace.c:3431 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3431 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x465f69 RSP: 002b:00007f3289ccc188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 000000000056c158 RCX: 0000000000465f69 RDX: 0000000020002000 RSI: 00000000200042c0 RDI: 0000000000000000 RBP: 00000000004bfa3f R08: 0000000020002240 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c158 R13: 00007fffdc762d6f R14: 00007f3289ccc300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1666: #0: ffffffff8bf74220 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6327 1 lock held by in:imklog/8297: #0: ffff88801b7e4af0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:961 2 locks held by agetty/8327: #0: ffff88801c348098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:266 #1: ffffc9000121c2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xd5b/0x12f0 drivers/tty/n_tty.c:2178 4 locks held by syz-executor.1/12339: 1 lock held by syz-executor.1/12368: #0: ffff8880316e0ed0 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline] #0: ffff8880316e0ed0 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: lock_mount+0x8a/0x2e0 fs/namespace.c:2216 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1666 Comm: khungtaskd Not tainted 5.12.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd48/0xfb0 kernel/hung_task.c:294 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4848 Comm: systemd-journal Not tainted 5.12.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:check_kcov_mode kernel/kcov.c:163 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x1c/0x60 kernel/kcov.c:197 Code: 45 00 48 63 c9 e9 64 ff ff ff 0f 1f 40 00 65 8b 05 c9 4f 8e 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b 14 25 00 f0 01 00 00 01 ff 00 74 0e 85 c9 74 35 8b 82 d4 14 00 00 85 c0 74 2b 8b RSP: 0018:ffffc9000165fa60 EFLAGS: 00000246 RAX: 0000000080000000 RBX: ffffffff8be34b88 RCX: 0000000000000000 RDX: ffff88801173b780 RSI: ffffffff816ff9c1 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff816ff9b5 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 00000000fffffffe R15: 0000000000000001 FS: 00007f08e431d8c0(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c01dc29020 CR3: 000000002658a000 CR4: 0000000000350ee0 Call Trace: map_id_range_down_base kernel/user_namespace.c:284 [inline] map_id_range_down+0x181/0x340 kernel/user_namespace.c:297 map_id_down kernel/user_namespace.c:312 [inline] make_kuid+0x1e/0x30 kernel/user_namespace.c:389 kuid_into_mnt include/linux/fs.h:1580 [inline] i_uid_into_mnt include/linux/fs.h:1592 [inline] acl_permission_check fs/namei.c:330 [inline] generic_permission+0x88/0x5b0 fs/namei.c:392 do_inode_permission fs/namei.c:453 [inline] inode_permission.part.0+0x95/0x440 fs/namei.c:513 inode_permission fs/namei.c:494 [inline] may_lookup fs/namei.c:1652 [inline] link_path_walk.part.0+0x26e/0xc90 fs/namei.c:2208 link_path_walk fs/namei.c:2190 [inline] path_lookupat+0xb7/0x830 fs/namei.c:2419 filename_lookup+0x19f/0x560 fs/namei.c:2453 user_path_at include/linux/namei.h:60 [inline] do_faccessat+0x127/0x850 fs/open.c:425 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f08e35d89c7 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:00007ffdbc89c238 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 00007ffdbc89f260 RCX: 00007f08e35d89c7 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000561c27d009a3 RBP: 00007ffdbc89c380 R08: 0000561c27cf63e5 R09: 0000000000000018 R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000561c28a618a0 R15: 00007ffdbc89c870