Hello, syzbot found the following issue on: HEAD commit: b831f83e40a2 Merge tag 'bpf-6.11-rc7' of git://git.kernel... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1565b43b980000 kernel config: https://syzkaller.appspot.com/x/.config?x=660f6eb11f9c7dc5 dashboard link: https://syzkaller.appspot.com/bug?extid=7bb5e48f6ead66c72906 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/c788afb419c2/disk-b831f83e.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/0692a9bfb15e/vmlinux-b831f83e.xz kernel image: https://storage.googleapis.com/syzbot-assets/e22aeda7a3e2/bzImage-b831f83e.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+7bb5e48f6ead66c72906@xxxxxxxxxxxxxxxxxxxxxxxxx INFO: task syz.4.402:7932 blocked for more than 143 seconds. Not tainted 6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.402 state:D stack:25792 pid:7932 tgid:7932 ppid:6207 flags:0x00000004 Call Trace: <TASK> context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752 hugetlb_fault+0x56f/0x3770 mm/hugetlb.c:6451 handle_mm_fault+0x1901/0x1bc0 mm/memory.c:5830 do_user_addr_fault arch/x86/mm/fault.c:1338 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x459/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f82a094497c RSP: 002b:00007f82a0c5fb88 EFLAGS: 00010246 RAX: 0000000020000d00 RBX: 0000000000000004 RCX: 8000000000000010 RDX: 0000000000000010 RSI: 00007f82a04005d5 RDI: 0000000020000d00 RBP: 00007f82a0b37a80 R08: 00007f82a0800000 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000009 R12: 0000000000038ce8 R13: 00007f82a0c5fc90 R14: 0000000000000032 R15: fffffffffffffffe </TASK> INFO: task syz.4.402:7933 blocked for more than 143 seconds. Not tainted 6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.402 state:D stack:24696 pid:7933 tgid:7932 ppid:6207 flags:0x00004006 Call Trace: <TASK> context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752 hugetlb_wp+0x104d/0x3a90 mm/hugetlb.c:6027 hugetlb_fault+0x27b2/0x3770 mm/hugetlb.c:6579 handle_mm_fault+0x1901/0x1bc0 mm/memory.c:5830 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0010:rep_movs_alternative+0x4a/0x70 arch/x86/lib/copy_user_64.S:71 Code: 75 f1 c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 48 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 df 83 f9 08 73 e8 eb c9 <f3> a4 c3 cc cc cc cc 48 89 c8 48 c1 e9 03 83 e0 07 f3 48 a5 89 c1 RSP: 0018:ffffc90004127ad0 EFLAGS: 00050246 RAX: ffffffff84b29101 RBX: 0000000020008640 RCX: 0000000000000040 RDX: 0000000000000000 RSI: ffffc90004127b60 RDI: 0000000020008600 RBP: ffffc90004127c10 R08: ffffc90004127b9f R09: 1ffff92000824f73 R10: dffffc0000000000 R11: fffff52000824f74 R12: 0000000000000040 R13: 0000000000007fc0 R14: 0000000020008600 R15: ffffc90004127b60 copy_user_generic arch/x86/include/asm/uaccess_64.h:110 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:131 [inline] _inline_copy_to_user include/linux/uaccess.h:181 [inline] _copy_to_user+0x86/0xb0 lib/usercopy.c:26 copy_to_user include/linux/uaccess.h:209 [inline] rng_dev_read+0x3be/0x6d0 drivers/char/hw_random/core.c:251 do_loop_readv_writev fs/read_write.c:761 [inline] vfs_readv+0x6c2/0xa90 fs/read_write.c:934 do_preadv fs/read_write.c:1049 [inline] __do_sys_preadv fs/read_write.c:1099 [inline] __se_sys_preadv fs/read_write.c:1094 [inline] __x64_sys_preadv+0x1c7/0x2d0 fs/read_write.c:1094 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f82a097cef9 RSP: 002b:00007f82a174d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000127 RAX: ffffffffffffffda RBX: 00007f82a0b35f80 RCX: 00007f82a097cef9 RDX: 0000000000000002 RSI: 0000000020000580 RDI: 0000000000000005 RBP: 00007f82a09ef01e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f82a0b35f80 R15: 00007f82a0c5fa28 </TASK> INFO: task syz.4.402:7934 blocked for more than 144 seconds. Not tainted 6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.402 state:D stack:23288 pid:7934 tgid:7932 ppid:6207 flags:0x00004006 Call Trace: <TASK> context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 io_schedule+0x8d/0x110 kernel/sched/core.c:7401 folio_wait_bit_common+0x882/0x12b0 mm/filemap.c:1307 __filemap_get_folio+0xb7/0xc10 mm/filemap.c:1898 hugetlb_fault+0x1b72/0x3770 mm/hugetlb.c:6531 handle_mm_fault+0x1901/0x1bc0 mm/memory.c:5830 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0010:__put_user_8+0x11/0x20 arch/x86/lib/putuser.S:107 Code: 84 00 00 00 00 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 89 cb 48 c1 fb 3f 48 09 d9 0f 01 cb <48> 89 01 31 c9 0f 01 ca c3 cc cc cc cc 66 90 90 90 90 90 90 90 90 RSP: 0018:ffffc9000383f778 EFLAGS: 00050202 RAX: 0000000000800000 RBX: 0000000000000000 RCX: 0000000020000020 RDX: 0000000000000000 RSI: ffffffff8c0ae6e0 RDI: ffffffff8c608d80 RBP: ffffc9000383fec8 R08: ffffffff901870ef R09: 1ffffffff2030e1d R10: dffffc0000000000 R11: fffffbfff2030e1e R12: 1ffff92000707f7d R13: 1ffff92000707f08 R14: 0000000020800000 R15: 0000000000800000 userfaultfd_copy fs/userfaultfd.c:1735 [inline] userfaultfd_ioctl+0x28e7/0x70a0 fs/userfaultfd.c:2133 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f82a097cef9 RSP: 002b:00007f82a172c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f82a0b36058 RCX: 00007f82a097cef9 RDX: 0000000020000000 RSI: 00000000c028aa03 RDI: 0000000000000009 RBP: 00007f82a09ef01e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f82a0b36058 R15: 00007f82a0c5fa28 </TASK> Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6626 1 lock held by dhcpcd/4900: #0: ffffffff8fc8be48 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1bc0 net/ipv4/devinet.c:1101 2 locks held by getty/4982: #0: ffff8880308270a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ac/0x1e00 drivers/tty/n_tty.c:2211 5 locks held by kworker/u8:12/7252: #0: ffff88801bae5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88801bae5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90009267d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90009267d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc7f290 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:594 #3: ffffffff8fc8be48 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xe9/0xa90 net/core/dev.c:11883 #4: ffffffff8e93d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:328 [inline] #4: ffffffff8e93d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:958 3 locks held by kworker/u8:13/7257: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90004ee7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90004ee7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc8be48 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 2 locks held by syz.4.402/7932: #0: ffff88807be333d0 (&vma->vm_lock->lock){++++}-{3:3}, at: vma_start_read include/linux/mm.h:694 [inline] #0: ffff88807be333d0 (&vma->vm_lock->lock){++++}-{3:3}, at: lock_vma_under_rcu+0x2f9/0x6e0 mm/memory.c:5998 #1: ffff8880206e6218 (&hugetlb_fault_mutex_table[i]){+.+.}-{3:3}, at: hugetlb_fault+0x56f/0x3770 mm/hugetlb.c:6451 2 locks held by syz.4.402/7933: #0: ffff8880352aa798 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock_killable+0x1d/0x70 include/linux/mmap_lock.h:153 #1: ffff8880206e6218 (&hugetlb_fault_mutex_table[i]){+.+.}-{3:3}, at: hugetlb_wp+0x104d/0x3a90 mm/hugetlb.c:6027 3 locks held by syz.4.402/7934: #0: ffff8880352aa798 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock_killable+0x1d/0x70 include/linux/mmap_lock.h:153 #1: ffff8880206e6218 (&hugetlb_fault_mutex_table[i]){+.+.}-{3:3}, at: hugetlb_fault+0x56f/0x3770 mm/hugetlb.c:6451 #2: ffff8880250d48e8 (&resv_map->rw_sema){++++}-{3:3}, at: hugetlb_fault+0x675/0x3770 mm/hugetlb.c:6458 2 locks held by syz.2.812/9374: #0: ffff888024984c40 (&vma->vm_lock->lock){++++}-{3:3}, at: vma_start_read include/linux/mm.h:694 [inline] #0: ffff888024984c40 (&vma->vm_lock->lock){++++}-{3:3}, at: lock_vma_under_rcu+0x2f9/0x6e0 mm/memory.c:5998 #1: ffff8880206e6218 (&hugetlb_fault_mutex_table[i]){+.+.}-{3:3}, at: hugetlb_fault+0x56f/0x3770 mm/hugetlb.c:6451 1 lock held by syz-executor/10950: #0: ffffffff8fc8be48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fc8be48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 1 lock held by syz.3.1233/10991: #0: ffffffff8fc8be48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fc8be48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 3 locks held by syz.3.1233/10996: #0: ffffffff8fcf15b0 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffff888062b59678 (nlk_cb_mutex-GENERIC){+.+.}-{3:3}, at: __netlink_dump_start+0x119/0x790 net/netlink/af_netlink.c:2404 #2: ffffffff8fc8be48 (rtnl_mutex){+.+.}-{3:3}, at: ethnl_default_dump_one net/ethtool/netlink.c:494 [inline] #2: ffffffff8fc8be48 (rtnl_mutex){+.+.}-{3:3}, at: ethnl_default_dumpit+0x411/0xb30 net/ethtool/netlink.c:529 2 locks held by syz.2.1230/11003: #0: ffffffff8fcf15b0 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8fc8be48 (rtnl_mutex){+.+.}-{3:3}, at: nl80211_pre_doit+0x5f/0x8b0 net/wireless/nl80211.c:16547 4 locks held by syz.1.1238/11010: #0: ffff88802f9a0d80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff88802f9a0d80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2698 #1: ffff88802f9a0078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x572/0x11a0 net/bluetooth/hci_sync.c:5183 #2: ffffffff8fdf7968 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1972 [inline] #2: ffffffff8fdf7968 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xa6/0x240 net/bluetooth/hci_conn.c:2592 #3: ffffffff8e93d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:328 [inline] #3: ffffffff8e93d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:958 1 lock held by syz.4.1239/11013: #0: ffffffff8fc8be48 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x48f/0x2400 drivers/net/tun.c:3120 1 lock held by syz.4.1239/11014: #0: ffffffff8fc8be48 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fc8be48 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3e/0x1b0 drivers/net/tun.c:3510 1 lock held by syz.4.1239/11015: #0: ffffffff8fc8be48 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x706/0x1340 net/core/dev_ioctl.c:783 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: <TASK> __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 7259 Comm: kworker/u8:14 Not tainted 6.11.0-rc6-syzkaller-00183-gb831f83e40a2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: 0x0 (bat_events) RIP: 0010:process_scheduled_works+0x1fd/0x1830 kernel/workqueue.c:3309 Code: e8 18 6f 9c 00 4c 8b 35 41 8d 02 0d 48 8b 5c 24 48 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 f6 6e 9c 00 48 8b 1b <48> 83 c3 50 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 RSP: 0018:ffffc900098c7bc0 EFLAGS: 00000046 RAX: 1ffff11005d68dcb RBX: ffff88801aca0000 RCX: ffff88806550bc00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900098c7dc0 R08: ffffffff815e648d R09: 1ffff110291e65b1 R10: dffffc0000000000 R11: ffffed10291e65b2 R12: dffffc0000000000 R13: ffff888064648660 R14: 0000000100001f4d R15: ffff888064648668 FS: 0000000000000000(0000) GS:ffff8880b8900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9e9a1f9000 CR3: 000000000e734000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <NMI> </NMI> <TASK> worker_thread+0x86d/0xd10 kernel/workqueue.c:3389 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup