netlink: 'syz-executor4': attribute type 2 has an invalid length. netlink: 'syz-executor4': attribute type 3 has an invalid length. INFO: task syz-executor3:572 blocked for more than 140 seconds. Not tainted 4.18.0-rc8+ #180 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D24376 572 4467 0x00000004 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ec0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 __rwsem_down_write_failed_common+0x95d/0x1630 kernel/locking/rwsem-xadd.c:566 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:595 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0xaa/0x130 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:715 [inline] vfs_removexattr+0x82/0x1c0 fs/xattr.c:391 removexattr+0xd3/0x130 fs/xattr.c:691 path_removexattr+0x1b9/0x210 fs/xattr.c:705 __do_sys_removexattr fs/xattr.c:719 [inline] __se_sys_removexattr fs/xattr.c:716 [inline] __x64_sys_removexattr+0x59/0x80 fs/xattr.c:716 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x456cb9 Code: 18 85 c0 75 12 48 8b 44 24 20 48 89 08 48 8b 6c 24 28 48 83 c4 30 c3 48 8b 44 24 20 48 89 04 24 48 89 4c 24 08 e8 e7 ac fb ff e1 e8 f0 31 00 00 e9 7b ff ff ff cc cc cc cc cc cc cc cc cc cc RSP: 002b:00007fb4dec7dc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000c5 RAX: ffffffffffffffda RBX: 00007fb4dec7e6d4 RCX: 0000000000456cb9 RDX: 0000000000000000 RSI: 0000000020000380 RDI: 00000000200004c0 RBP: 0000000000930140 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d2f88 R14: 00000000004c2fe7 R15: 0000000000000001 INFO: task syz-executor3:573 blocked for more than 140 seconds. Not tainted 4.18.0-rc8+ #180 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D24088 573 4467 0x00000004 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ec0 kernel/sched/core.c:3501 schedule+0xfb/0x450 kernel/sched/core.c:3545 __rwsem_down_write_failed_common+0x95d/0x1630 kernel/locking/rwsem-xadd.c:566 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:595 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0xaa/0x130 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:715 [inline] lock_mount+0x8c/0x2e0 fs/namespace.c:2088 do_add_mount+0x27/0x370 fs/namespace.c:2465 do_new_mount fs/namespace.c:2532 [inline] do_mount+0x193f/0x30e0 fs/namespace.c:2848 ksys_mount+0x12d/0x140 fs/namespace.c:3064 __do_sys_mount fs/namespace.c:3078 [inline] __se_sys_mount fs/namespace.c:3075 [inline] __x64_sys_mount+0xbe/0x150 fs/namespace.c:3075 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x456cb9 Code: 18 85 c0 75 12 48 8b 44 24 20 48 89 08 48 8b 6c 24 28 48 83 c4 30 c3 48 8b 44 24 20 48 89 04 24 48 89 4c 24 08 e8 e7 ac fb ff e1 e8 f0 31 00 00 e9 7b ff ff ff cc cc cc cc cc cc cc cc cc cc RSP: 002b:00007fb4dec5cc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fb4dec5d6d4 RCX: 0000000000456cb9 RDX: 0000000020000900 RSI: 0000000020000000 RDI: 0000000000000000 RBP: 00000000009301e0 R08: 0000000020000840 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004d1e90 R14: 00000000004c75cc R15: 0000000000000002 Showing all locks held in the system: 1 lock held by khungtaskd/774: #0: 000000003cb5911c (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x428 kernel/locking/lockdep.c:4461 1 lock held by rsyslogd/4324: 2 locks held by getty/4414: #0: 000000006cdcf369 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000f27a37db (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4415: #0: 0000000039294b40 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000084ae1238 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4416: #0: 0000000084faf6f6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000dfcb3908 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4417: #0: 0000000095ac138a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000fc974ed8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4418: #0: 000000001bf1bdb4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000005d737cb0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4419: #0: 00000000598e3b7d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000007eb49150 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4420: #0: 00000000e1885a6b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000041a41b67 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by syz-executor3/496: #0: 00000000921527e4 (sb_writers#14){.+.+}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 00000000921527e4 (sb_writers#14){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 #1: 000000006cf71f7d (&sb->s_type->i_mutex_key#22){++++}, at: inode_lock include/linux/fs.h:715 [inline] #1: 000000006cf71f7d (&sb->s_type->i_mutex_key#22){++++}, at: vfs_removexattr+0x82/0x1c0 fs/xattr.c:391 2 locks held by syz-executor3/572: #0: 00000000921527e4 (sb_writers#14){.+.+}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 00000000921527e4 (sb_writers#14){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 #1: 000000006cf71f7d (&sb->s_type->i_mutex_key#22){++++}, at: inode_lock include/linux/fs.h:715 [inline] #1: 000000006cf71f7d (&sb->s_type->i_mutex_key#22){++++}, at: vfs_removexattr+0x82/0x1c0 fs/xattr.c:391 1 lock held by syz-executor3/573: #0: 000000006cf71f7d (&sb->s_type->i_mutex_key#22){++++}, at: inode_lock include/linux/fs.h:715 [inline] #0: 000000006cf71f7d (&sb->s_type->i_mutex_key#22){++++}, at: lock_mount+0x8c/0x2e0 fs/namespace.c:2088 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 774 Comm: khungtaskd Not tainted 4.18.0-rc8+ #180 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+0x1c9/0x2b4 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103 nmi_trigger_cpumask_backtrace+0x151/0x192 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:138 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:196 [inline] watchdog+0x9c4/0xf80 kernel/hung_task.c:252 kthread+0x345/0x410 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54