netlink: 20 bytes leftover after parsing attributes in process `syz-executor.3'. netlink: 20 bytes leftover after parsing attributes in process `syz-executor.1'. INFO: task syz-executor.0:15163 blocked for more than 140 seconds. Not tainted 4.19.107-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28512 15163 8089 0x00000004 Call Trace: schedule+0x8d/0x1b0 kernel/sched/core.c:3559 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x774/0xc30 kernel/locking/rwsem-xadd.c:618 call_rwsem_down_write_failed+0x13/0x20 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0x4f/0x90 kernel/locking/rwsem.c:72 prealloc_memcg_shrinker mm/vmscan.c:194 [inline] prealloc_shrinker+0x16f/0x340 mm/vmscan.c:382 alloc_super fs/super.c:265 [inline] sget_userns+0x773/0xcd0 fs/super.c:519 sget+0x10d/0x150 fs/super.c:570 mount_bdev+0xf8/0x3c0 fs/super.c:1131 mount_fs+0xa3/0x30c fs/super.c:1261 vfs_kern_mount.part.0+0x68/0x400 fs/namespace.c:961 vfs_kern_mount fs/namespace.c:951 [inline] do_new_mount fs/namespace.c:2469 [inline] do_mount+0x4f4/0x2a40 fs/namespace.c:2799 ksys_mount+0xd7/0x150 fs/namespace.c:3015 __do_sys_mount fs/namespace.c:3029 [inline] __se_sys_mount fs/namespace.c:3026 [inline] __x64_sys_mount+0xba/0x150 fs/namespace.c:3026 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45eeca Code: b8 a6 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 4d 8c fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 2a 8c fb ff c3 66 0f 1f 84 00 00 00 00 00 RSP: 002b:00007f06e4cfda68 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f06e4cfe6d4 RCX: 000000000045eeca RDX: 00007f06e4cfdae0 RSI: 00000000200000c0 RDI: 00007f06e4cfdb00 RBP: 000000000076bf20 R08: 00007f06e4cfdb40 R09: 00007f06e4cfdae0 R10: 0000000000000000 R11: 0000000000000202 R12: 00000000ffffffff R13: 0000000000000be1 R14: 00000000004cdc2d R15: 000000000076bf2c Showing all locks held in the system: 1 lock held by khungtaskd/1075: #0: 000000005227c2f9 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4436 3 locks held by khugepaged/1087: 1 lock held by rsyslogd/7926: #0: 0000000008ab73ae (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:767 2 locks held by getty/8049: #0: 0000000029d59ee0 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000c88107eb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154 2 locks held by getty/8050: #0: 000000003481fe79 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000001a6a52da (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154 2 locks held by getty/8051: #0: 00000000718b1b05 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000e0d1b648 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154 2 locks held by getty/8052: #0: 0000000049e58dd8 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000e11e84d7 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154 2 locks held by getty/8053: #0: 0000000074fe34d8 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000a35c1cb9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154 2 locks held by getty/8054: #0: 00000000ba07eb36 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000000620fd35 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154 2 locks held by getty/8055: #0: 00000000df3e6ae0 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000569b80b3 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154 3 locks held by kworker/u4:7/10021: 1 lock held by syz-executor.4/30045: 1 lock held by syz-executor.2/30284: 1 lock held by syz-executor.2/31205: 1 lock held by syz-executor.2/31220: 1 lock held by syz-executor.4/31221: #0: 00000000ace05cf7 (&vcpu->mutex){+.+.}, at: kvm_vcpu_ioctl+0x175/0xe20 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2644 1 lock held by syz-executor.4/31691: #0: 000000000c7562cd (&vcpu->mutex){+.+.}, at: kvm_vcpu_ioctl+0x175/0xe20 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2644 1 lock held by syz-executor.2/481: 1 lock held by syz-executor.1/1514: #0: 00000000c7af6023 (&vcpu->mutex){+.+.}, at: kvm_vcpu_ioctl+0x175/0xe20 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2644 1 lock held by syz-executor.5/1534: #0: 0000000064d8e3e7 (&vcpu->mutex){+.+.}, at: kvm_vcpu_ioctl+0x175/0xe20 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2644 1 lock held by syz-executor.5/1553: #0: 00000000daf18830 (&vcpu->mutex){+.+.}, at: kvm_vcpu_ioctl+0x175/0xe20 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2644 3 locks held by syz-executor.0/15163: #0: 00000000e1bf2ca3 (&bdev->bd_fsfreeze_mutex){+.+.}, at: mount_bdev+0x90/0x3c0 fs/super.c:1125 #1: 00000000781959e6 (&type->s_umount_key#63/1){+.+.}, at: alloc_super fs/super.c:226 [inline] #1: 00000000781959e6 (&type->s_umount_key#63/1){+.+.}, at: sget_userns+0x1fc/0xcd0 fs/super.c:519 #2: 0000000076b87c88 (shrinker_rwsem){++++}, at: prealloc_memcg_shrinker mm/vmscan.c:194 [inline] #2: 0000000076b87c88 (shrinker_rwsem){++++}, at: prealloc_shrinker+0x16f/0x340 mm/vmscan.c:382 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1075 Comm: khungtaskd Not tainted 4.19.107-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+0x188/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 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+0x962/0xe40 kernel/hung_task.c:287 kthread+0x34a/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 1553 Comm: syz-executor.5 Not tainted 4.19.107-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:lockdep_hardirqs_on+0x262/0x5d0 kernel/locking/lockdep.c:2880 Code: 03 8d 68 01 48 b8 00 00 00 00 00 fc ff df 89 ab 28 08 00 00 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 93 02 00 00 89 ab 40 08 00 00 <65> 48 8b 1c 25 40 ee 01 00 48 8d bb 7c 08 00 00 48 b8 00 00 00 00 RSP: 0018:ffff88805a8b75e8 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff888060c72400 RCX: 1ffff1100c18e594 RDX: 1ffff1100c18e588 RSI: ffff888060c72c80 RDI: ffff888060c72c40 RBP: 0000000001a9cde5 R08: ffff888060c72400 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f24ec865700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c43d6f1b98 CR3: 0000000092298000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trace_hardirqs_on_thunk+0x1a/0x1c