syz-executor784[8006]: segfault at 0 ip 000000000043bd4e sp 00007f4c7108b188 error 4 in syz-executor784477392[401000+9a000] syz-executor784[8008]: segfault at 0 ip 000000000043bd4e sp 00007f4c7108b188 error 4 in syz-executor784477392[401000+9a000] in syz-executor784477392[401000+9a000] INFO: task syz-executor784:7986 blocked for more than 140 seconds. Not tainted 4.14.232-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor784 D29920 7986 7977 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 mount_bdev+0x71/0x360 fs/super.c:1101 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0xe53/0x2a00 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x44a329 RSP: 002b:00007f4c710ac318 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00000000004cb408 RCX: 000000000044a329 RDX: 0000000020000000 RSI: 0000000020000180 RDI: 0000000020000380 RBP: 00000000004cb400 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e R13: 00007fffdc4d335f R14: 00007f4c710ac400 R15: 0000000000022000 INFO: task syz-executor784:7982 blocked for more than 140 seconds. Not tainted 4.14.232-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor784 D29848 7982 7975 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:588 [inline] rwsem_down_write_failed+0x343/0x6d0 kernel/locking/rwsem-xadd.c:617 call_rwsem_down_write_failed+0x13/0x20 arch/x86/lib/rwsem.S:105 __down_write arch/x86/include/asm/rwsem.h:126 [inline] down_write+0x4f/0x90 kernel/locking/rwsem.c:56 grab_super+0x55/0x140 fs/super.c:373 sget_userns+0x2b1/0xc10 fs/super.c:504 sget+0xd1/0x110 fs/super.c:572 mount_bdev+0xcd/0x360 fs/super.c:1107 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0xe53/0x2a00 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x44a329 RSP: 002b:00007f4c710ac318 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00000000004cb408 RCX: 000000000044a329 RDX: 0000000020000000 RSI: 0000000020000180 RDI: 0000000020000380 RBP: 00000000004cb400 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e R13: 00007fffdc4d335f R14: 00007f4c710ac400 R15: 0000000000022000 INFO: task syz-executor784:7990 blocked for more than 140 seconds. Not tainted 4.14.232-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor784 D29920 7990 7972 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 mount_bdev+0x71/0x360 fs/super.c:1101 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0xe53/0x2a00 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x44a329 RSP: 002b:00007f4c710ac318 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00000000004cb408 RCX: 000000000044a329 RDX: 0000000020000000 RSI: 0000000020000180 RDI: 0000000020000380 RBP: 00000000004cb400 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e R13: 00007fffdc4d335f R14: 00007f4c710ac400 R15: 0000000000022000 INFO: task syz-executor784:7991 blocked for more than 140 seconds. Not tainted 4.14.232-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor784 D29920 7991 7976 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 mount_bdev+0x71/0x360 fs/super.c:1101 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0xe53/0x2a00 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x44a329 RSP: 002b:00007f4c710ac318 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00000000004cb408 RCX: 000000000044a329 RDX: 0000000020000000 RSI: 0000000020000180 RDI: 0000000020000380 RBP: 00000000004cb400 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e R13: 00007fffdc4d335f R14: 00007f4c710ac400 R15: 0000000000022000 INFO: task syz-executor784:7989 blocked for more than 140 seconds. Not tainted 4.14.232-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor784 D29920 7989 7974 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 mount_bdev+0x71/0x360 fs/super.c:1101 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0xe53/0x2a00 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x44a329 RSP: 002b:00007f4c710ac318 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00000000004cb408 RCX: 000000000044a329 RDX: 0000000020000000 RSI: 0000000020000180 RDI: 0000000020000380 RBP: 00000000004cb400 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e R13: 00007fffdc4d335f R14: 00007f4c710ac400 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1533: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 1 lock held by syz-executor784/7986: #0: (&bdev->bd_fsfreeze_mutex){+.+.}, at: [] mount_bdev+0x71/0x360 fs/super.c:1101 2 locks held by syz-executor784/7982: #0: (&bdev->bd_fsfreeze_mutex){+.+.}, at: [] mount_bdev+0x71/0x360 fs/super.c:1101 #1: (&type->s_umount_key#47){+.+.}, at: [] grab_super+0x55/0x140 fs/super.c:373 1 lock held by syz-executor784/7990: #0: (&bdev->bd_fsfreeze_mutex){+.+.}, at: [] mount_bdev+0x71/0x360 fs/super.c:1101 1 lock held by syz-executor784/7991: #0: (&bdev->bd_fsfreeze_mutex){+.+.}, at: [] mount_bdev+0x71/0x360 fs/super.c:1101 1 lock held by syz-executor784/7989: #0: (&bdev->bd_fsfreeze_mutex){+.+.}, at: [] mount_bdev+0x71/0x360 fs/super.c:1101 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1533 Comm: khungtaskd Not tainted 4.14.232-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5b9/0xb40 kernel/hung_task.c:274 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8 Comm: rcu_preempt Not tainted 4.14.232-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8880b5414200 task.stack: ffff8880b5418000 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:23 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0xe/0x50 kernel/kcov.c:65 RSP: 0018:ffff8880b541fc70 EFLAGS: 00000286 RAX: ffff8880b5414200 RBX: ffff8880b541fd18 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000297 RBP: ffff8880b541fd48 R08: ffffffff8b9b3610 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000297 R13: ffff8880ba522ac0 R14: ffff8880b541fd18 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa8c3dad000 CR3: 00000000b0219000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: del_timer_sync+0x174/0x240 kernel/time/timer.c:1246 schedule_timeout+0x4b7/0xe90 kernel/time/timer.c:1748 rcu_gp_kthread+0xc0a/0x1e60 kernel/rcu/tree.c:2255 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Code: ff 4c 89 e7 e8 44 a5 29 00 e9 2c fe ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 65 48 8b 04 25 80 df 01 00 48 85 c0 74 1a <65> 8b 15 8b b9 ac 7e 81 e2 00 01 1f 00 75 0b 8b 90 58 13 00 00