netlink: 16 bytes leftover after parsing attributes in process `syz-executor0'. netlink: 16 bytes leftover after parsing attributes in process `syz-executor0'. INFO: task syz-executor5:14548 blocked for more than 140 seconds. Not tainted 4.18.0-rc4+ #138 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor5 D24752 14548 4547 0x00000004 Call Trace: context_switch kernel/sched/core.c:2853 [inline] __schedule+0x87c/0x1ed0 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: 0033:0x455e29 Code: cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 0f 86 ab 04 00 00 48 83 ec 58 48 89 6c 24 50 48 8d 6c 24 50 48 8b 44 24 60 c6 00 00 <48> 8b 4c 24 68 48 89 ca 48 89 50 08 48 8b 59 20 48 01 da 31 db 31 RSP: 002b:00007f4465180c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000c5 RAX: ffffffffffffffda RBX: 00007f44651816d4 RCX: 0000000000455e29 RDX: 0000000000000000 RSI: 0000000020000400 RDI: 0000000020000380 RBP: 000000000072bf48 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004bbfeb R14: 00000000004d1108 R15: 0000000000000001 Showing all locks held in the system: 1 lock held by khungtaskd/901: #0: 00000000ebf24c36 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x428 kernel/locking/lockdep.c:4461 1 lock held by rsyslogd/4405: 2 locks held by getty/4495: #0: 00000000692a9d2f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000072fe5412 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4496: #0: 000000002b623882 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000056c15f7c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4497: #0: 000000002c1f858b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000048aba06b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4498: #0: 00000000da02f89a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000004a06c40f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4499: #0: 0000000017508207 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000a4b24877 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4500: #0: 0000000079a247d3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000009bcfd45d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/4501: #0: 00000000e73958a9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000007d96a629 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by syz-executor5/14500: #0: 00000000ba1ef7f9 (sb_writers#19){.+.+}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 00000000ba1ef7f9 (sb_writers#19){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 #1: 00000000e4cbde96 (&sb->s_type->i_mutex_key#25){++++}, at: inode_lock include/linux/fs.h:715 [inline] #1: 00000000e4cbde96 (&sb->s_type->i_mutex_key#25){++++}, at: vfs_removexattr+0x82/0x1c0 fs/xattr.c:391 2 locks held by syz-executor5/14548: #0: 00000000ba1ef7f9 (sb_writers#19){.+.+}, at: sb_start_write include/linux/fs.h:1554 [inline] #0: 00000000ba1ef7f9 (sb_writers#19){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:386 #1: 00000000e4cbde96 (&sb->s_type->i_mutex_key#25){++++}, at: inode_lock include/linux/fs.h:715 [inline] #1: 00000000e4cbde96 (&sb->s_type->i_mutex_key#25){++++}, at: vfs_removexattr+0x82/0x1c0 fs/xattr.c:391 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 901 Comm: khungtaskd Not tainted 4.18.0-rc4+ #138 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 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54