netlink: 4 bytes leftover after parsing attributes in process `syz-executor.5'. netlink: 4 bytes leftover after parsing attributes in process `syz-executor.5'. INFO: task syz-executor.1:9664 blocked for more than 140 seconds. Not tainted 4.19.77 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D29520 9664 7540 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x866/0x1dc0 kernel/sched/core.c:3515 schedule+0x92/0x1c0 kernel/sched/core.c:3559 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline] rwsem_down_read_failed+0x21b/0x3c0 kernel/locking/rwsem-xadd.c:309 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94 __down_read arch/x86/include/asm/rwsem.h:83 [inline] down_read+0x49/0xb0 kernel/locking/rwsem.c:26 iterate_supers+0xe2/0x290 fs/super.c:631 ksys_sync+0x90/0x160 fs/sync.c:113 __ia32_sys_sync+0xe/0x20 fs/sync.c:124 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459a59 Code: 70 c0 00 48 83 fb 10 7c 6e 49 c7 c4 00 00 00 00 48 89 f7 48 83 fb 20 0f 87 c8 00 00 00 48 8d 44 1e f0 eb 17 f3 0f 6f 0f 66 0f <74> c8 66 0f d7 d1 f3 0f b8 d2 49 01 d4 48 83 c7 10 48 39 c7 76 e4 RSP: 002b:00007fe488f7bc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 000000000075bfd0 RCX: 0000000000459a59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe488f7c6d4 R13: 00000000004c68f9 R14: 00000000004dfee8 R15: 00000000ffffffff INFO: task syz-executor.1:9672 blocked for more than 140 seconds. Not tainted 4.19.77 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28080 9672 7540 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x866/0x1dc0 kernel/sched/core.c:3515 schedule+0x92/0x1c0 kernel/sched/core.c:3559 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline] rwsem_down_read_failed+0x21b/0x3c0 kernel/locking/rwsem-xadd.c:309 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94 __down_read arch/x86/include/asm/rwsem.h:83 [inline] down_read+0x49/0xb0 kernel/locking/rwsem.c:26 iterate_supers+0xe2/0x290 fs/super.c:631 ksys_sync+0x90/0x160 fs/sync.c:113 __ia32_sys_sync+0xe/0x20 fs/sync.c:124 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459a59 Code: 70 c0 00 48 83 fb 10 7c 6e 49 c7 c4 00 00 00 00 48 89 f7 48 83 fb 20 0f 87 c8 00 00 00 48 8d 44 1e f0 eb 17 f3 0f 6f 0f 66 0f <74> c8 66 0f d7 d1 f3 0f b8 d2 49 01 d4 48 83 c7 10 48 39 c7 76 e4 RSP: 002b:00007fe488f5ac78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 000000000075c078 RCX: 0000000000459a59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe488f5b6d4 R13: 00000000004c68f9 R14: 00000000004dfee8 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1040: #0: 00000000144db721 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4438 1 lock held by rsyslogd/7370: 2 locks held by getty/7492: #0: 00000000c9d1c3a7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000023c87eb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7493: #0: 00000000faa310aa (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000bc1a2d22 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7494: #0: 000000002c1135d5 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000da995569 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7495: #0: 000000008b4c6601 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000048485529 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7496: #0: 000000009ca701b4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000c6d72083 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7497: #0: 0000000093ba33c6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000bf0721a1 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 2 locks held by getty/7498: #0: 000000009b519f2e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000003ec89d7a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154 1 lock held by syz-executor.2/9649: #0: 000000000cd46d37 (&type->s_umount_key#72/1){+.+.}, at: alloc_super fs/super.c:226 [inline] #0: 000000000cd46d37 (&type->s_umount_key#72/1){+.+.}, at: sget_userns+0x208/0xd30 fs/super.c:519 1 lock held by syz-executor.2/9654: #0: 000000006c46e7af (&type->s_umount_key#72/1){+.+.}, at: alloc_super fs/super.c:226 [inline] #0: 000000006c46e7af (&type->s_umount_key#72/1){+.+.}, at: sget_userns+0x208/0xd30 fs/super.c:519 1 lock held by syz-executor.1/9664: #0: 000000006c46e7af (&type->s_umount_key#73){.+.+}, at: iterate_supers+0xe2/0x290 fs/super.c:631 1 lock held by syz-executor.1/9672: #0: 000000006c46e7af (&type->s_umount_key#73){.+.+}, at: iterate_supers+0xe2/0x290 fs/super.c:631 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1040 Comm: khungtaskd Not tainted 4.19.77 #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+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b0/0x1f8 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:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x9df/0xee0 kernel/hung_task.c:287 kthread+0x354/0x420 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 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60