new mount options do not match the existing superblock, will be ignored INFO: task syz-executor.4:12184 blocked for more than 140 seconds. Not tainted 4.19.211-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D26968 12184 8124 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 schedule_timeout+0x92d/0xfe0 kernel/time/timer.c:1794 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common+0x29c/0x470 kernel/sched/completion.c:115 __flush_work+0x4bb/0x8b0 kernel/workqueue.c:2926 __cancel_work_timer+0x412/0x590 kernel/workqueue.c:3013 p9_conn_destroy net/9p/trans_fd.c:904 [inline] p9_fd_close+0x305/0x520 net/9p/trans_fd.c:934 p9_client_create+0x901/0x12e0 net/9p/client.c:1084 v9fs_session_init+0x1dd/0x1770 fs/9p/v9fs.c:421 v9fs_mount+0x73/0x910 fs/9p/vfs_super.c:135 mount_fs+0xa3/0x310 fs/super.c:1261 vfs_kern_mount.part.0+0x68/0x470 fs/namespace.c:961 vfs_kern_mount fs/namespace.c:951 [inline] do_new_mount fs/namespace.c:2492 [inline] do_mount+0x115c/0x2f50 fs/namespace.c:2822 ksys_mount+0xcf/0x130 fs/namespace.c:3038 __do_sys_mount fs/namespace.c:3052 [inline] __se_sys_mount fs/namespace.c:3049 [inline] __x64_sys_mount+0xba/0x150 fs/namespace.c:3049 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f1f867575a9 Code: Bad RIP value. RSP: 002b:00007f1f84cca168 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f1f86877f80 RCX: 00007f1f867575a9 RDX: 0000000020000100 RSI: 0000000020000080 RDI: 0000000000000000 RBP: 00007f1f867b27b0 R08: 0000000020000180 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffecaccbcff R14: 00007f1f84cca300 R15: 0000000000022000 Showing all locks held in the system: 3 locks held by kworker/u4:1/23: #0: 000000001093d942 ((wq_completion)"%s""netns"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 000000000e5a2e2a (net_cleanup_work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 #2: 000000006bb2f9ba (pernet_ops_rwsem){++++}, at: cleanup_net+0xa8/0x8b0 net/core/net_namespace.c:521 1 lock held by khungtaskd/1570: #0: 00000000f2d707e6 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7800: #0: 0000000026dd931e (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 2 locks held by kworker/1:6/15212: #0: 000000007d797a5b ((wq_completion)"events"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 000000005a6ea3ed ((work_completion)(&m->wq)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1570 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 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+0x991/0xe60 kernel/hung_task.c:287 kthread+0x33f/0x460 kernel/kthread.c:259 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: 9 Comm: ksoftirqd/0 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022 RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:777 [inline] RIP: 0010:debug_check_no_obj_freed+0xf1/0x490 lib/debugobjects.c:817 Code: 00 48 8b 44 24 28 4c 8b 00 4d 85 c0 0f 84 35 02 00 00 49 bc 00 02 00 00 00 00 ad de 4c 89 c0 31 ed 48 c1 e8 03 42 80 3c 38 00 <0f> 85 dd 00 00 00 49 8d 78 18 83 c5 01 4d 8b 30 48 89 f8 48 c1 e8 RSP: 0018:ffff8880b5a5fb78 EFLAGS: 00000046 RAX: 1ffff110156b6b2d RBX: 0000000000000000 RCX: ffffffff814bdebb RDX: 1ffffffff1a7e1a3 RSI: 0000000000000004 RDI: ffffffff8d3f0d08 RBP: 0000000000000000 R08: ffff8880ab5b5968 R09: fffffbfff1a7e1a1 R10: ffffffff8d3f0d0b R11: 0000000000000000 R12: dead000000000200 R13: ffff8880980af540 R14: ffff8880a5de6c50 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb982737000 CR3: 00000000a0e49000 CR4: 00000000003406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kfree+0xb9/0x210 mm/slab.c:3821 security_sk_free+0x3e/0x70 security/security.c:1474 sk_prot_free net/core/sock.c:1516 [inline] __sk_destruct+0x51d/0x8a0 net/core/sock.c:1602 sk_destruct net/core/sock.c:1617 [inline] __sk_free+0x165/0x3b0 net/core/sock.c:1628 sk_free+0x3b/0x50 net/core/sock.c:1639 deferred_put_nlk_sk+0x10d/0x280 net/netlink/af_netlink.c:748 __rcu_reclaim kernel/rcu/rcu.h:236 [inline] rcu_do_batch kernel/rcu/tree.c:2584 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2897 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2864 [inline] rcu_process_callbacks+0x8ff/0x18b0 kernel/rcu/tree.c:2881 __do_softirq+0x265/0x980 kernel/softirq.c:292 run_ksoftirqd+0x57/0x110 kernel/softirq.c:653 smpboot_thread_fn+0x655/0x9e0 kernel/smpboot.c:164 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415