Hello, syzbot found the following issue on: HEAD commit: 6b0f8db921ab Merge tag 'execve-v6.11-rc4' of git://git.ker.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=16509e8d980000 kernel config: https://syzkaller.appspot.com/x/.config?x=801d05d1ea4be1b8 dashboard link: https://syzkaller.appspot.com/bug?extid=c391aebb8e8e8cd95c55 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/8e1d5e5016fb/disk-6b0f8db9.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/0487df01ffef/vmlinux-6b0f8db9.xz kernel image: https://storage.googleapis.com/syzbot-assets/cc8e8e0932d5/bzImage-6b0f8db9.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+c391aebb8e8e8cd95c55@xxxxxxxxxxxxxxxxxxxxxxxxx INFO: task syz.3.186:6037 blocked for more than 143 seconds. Not tainted 6.11.0-rc3-syzkaller-00013-g6b0f8db921ab #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.186 state:D stack:25688 pid:6037 tgid:6037 ppid:5773 flags:0x00004004 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+0x26de/0x3780 mm/hugetlb.c:6579 handle_mm_fault+0x173f/0x1980 mm/memory.c:5831 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: 0033:0x7f31cf341498 RSP: 002b:00007f31cf63fb98 EFLAGS: 00010246 RAX: 0000000020000080 RBX: 0000000000000004 RCX: 0070616d65676170 RDX: 0000000000000008 RSI: 0070616d65676170 RDI: 0000000020000080 RBP: 00007f31cf63fc70 R08: 00007f31cf200000 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000009 R12: 0000000000000032 R13: 00007f31cf63fc90 R14: 00007f31cf63fcb0 R15: fffffffffffffffe </TASK> INFO: task syz.3.186:6038 blocked for more than 143 seconds. Not tainted 6.11.0-rc3-syzkaller-00013-g6b0f8db921ab #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.186 state:D stack:22360 pid:6038 tgid:6037 ppid:5773 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+0x1b10/0x3780 mm/hugetlb.c:6531 handle_mm_fault+0x173f/0x1980 mm/memory.c:5831 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:ffffc9000317f778 EFLAGS: 00050202 RAX: 0000000000800000 RBX: 0000000000000000 RCX: 0000000020000020 RDX: 0000000000000000 RSI: ffffffff8c0ae6e0 RDI: ffffffff8c606400 RBP: ffffc9000317fec8 R08: ffffffff9017ce2f R09: 1ffffffff202f9c5 R10: dffffc0000000000 R11: fffffbfff202f9c6 R12: 1ffff9200062ff7d R13: 1ffff9200062ff08 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: 0033:0x7f31cf3799f9 RSP: 002b:00007f31d00e5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f31cf515f80 RCX: 00007f31cf3799f9 RDX: 0000000020000000 RSI: 00000000c028aa03 RDI: 0000000000000004 RBP: 00007f31cf3e78ee R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f31cf515f80 R15: 00007f31cf63fa38 </TASK> Showing all locks held in the system: 3 locks held by kworker/1:0/25: 1 lock held by khungtaskd/30: #0: ffffffff8e9382e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8e9382e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e9382e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6626 3 locks held by kworker/u8:2/35: 3 locks held by kworker/1:1/46: #0: ffff888015880948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff888015880948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90000b67d00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90000b67d00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffff888062701240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x2d1/0x4130 drivers/net/netdevsim/fib.c:1489 3 locks held by kworker/u8:3/52: #0: ffff888015889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff888015889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90000bc7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90000bc7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc82308 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 4 locks held by kworker/u8:10/2503: #0: ffff8880166e5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff8880166e5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90008c67d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90008c67d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc75790 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:594 #3: ffffffff8fc82308 (rtnl_mutex){+.+.}-{3:3}, at: fib_net_exit_batch+0x20/0x90 net/ipv4/fib_frontend.c:1638 1 lock held by dhcpcd/4896: #0: ffffffff8fc82308 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1bc0 net/ipv4/devinet.c:1101 2 locks held by getty/4983: #0: ffff88802af030a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ac/0x1e00 drivers/tty/n_tty.c:2211 1 lock held by syz-executor/5218: 3 locks held by kworker/0:4/5282: #0: ffff888015880948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff888015880948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90004017d00 ((fqdir_free_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90004017d00 ((fqdir_free_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8e93d580 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:4486 2 locks held by syz.3.186/6037: #0: ffff888063f3fd18 (&vma->vm_lock->lock){++++}-{3:3}, at: vma_start_read include/linux/mm.h:690 [inline] #0: ffff888063f3fd18 (&vma->vm_lock->lock){++++}-{3:3}, at: lock_vma_under_rcu+0x2f9/0x6e0 mm/memory.c:5999 #1: ffff88801baea0f8 (&hugetlb_fault_mutex_table[i]){+.+.}-{3:3}, at: hugetlb_wp+0x104d/0x3a90 mm/hugetlb.c:6027 3 locks held by syz.3.186/6038: #0: ffff88805a331e18 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:163 [inline] #0: ffff88805a331e18 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5870 [inline] #0: ffff88805a331e18 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:5930 #1: ffff88801baea0f8 (&hugetlb_fault_mutex_table[i]){+.+.}-{3:3}, at: hugetlb_fault+0x575/0x3780 mm/hugetlb.c:6451 #2: ffff888028c88ce8 (&resv_map->rw_sema){.+.+}-{3:3}, at: hugetlb_fault+0x67b/0x3780 mm/hugetlb.c:6458 2 locks held by syz.3.425/7080: #0: ffff88801cf73b68 (&vma->vm_lock->lock){++++}-{3:3}, at: vma_start_read include/linux/mm.h:690 [inline] #0: ffff88801cf73b68 (&vma->vm_lock->lock){++++}-{3:3}, at: lock_vma_under_rcu+0x2f9/0x6e0 mm/memory.c:5999 #1: ffff88801baea0f8 (&hugetlb_fault_mutex_table[i]){+.+.}-{3:3}, at: hugetlb_fault+0x575/0x3780 mm/hugetlb.c:6451 2 locks held by syz-executor/7564: #0: ffffffff8fc82308 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fc82308 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3e/0x1b0 drivers/net/tun.c:3510 #1: ffffffff8e93d6b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:296 [inline] #1: ffffffff8e93d6b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:958 1 lock held by syz-executor/8404: #0: ffffffff8fc82308 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fc82308 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 1 lock held by syz.2.726/8553: #0: ffffffff8fc82308 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x639/0x1340 net/core/dev_ioctl.c:737 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc3-syzkaller-00013-g6b0f8db921ab #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 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+0xfee/0x1030 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: 46 Comm: kworker/1:1 Not tainted 6.11.0-rc3-syzkaller-00013-g6b0f8db921ab #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Workqueue: events nsim_dev_trap_report_work RIP: 0010:get_current arch/x86/include/asm/current.h:49 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:215 Code: 8b 3d 7c db 95 0c 48 89 de 5b e9 03 94 5b 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 8b 04 24 <65> 48 8b 0c 25 40 d7 03 00 65 8b 15 a0 5f 70 7e 81 e2 00 01 ff 00 RSP: 0018:ffffc90000b67498 EFLAGS: 00000202 RAX: ffffffff81413211 RBX: ffffffff909bed9c RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffc90000b67670 RBP: ffffc90000b675e0 R08: ffffffff8141454b R09: ffffffff814130bf R10: 0000000000000003 R11: ffff88801becbc00 R12: ffffc90000b67678 R13: dffffc0000000000 R14: ffffc90000b67630 R15: 1ffff9200016cebc FS: 0000000000000000(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2a2c5c CR3: 0000000022eec000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <NMI> </NMI> <TASK> unwind_next_frame+0x1ac1/0x2a00 arch/x86/kernel/unwind_orc.c:648 __unwind_start+0x641/0x7c0 arch/x86/kernel/unwind_orc.c:760 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0x103/0x1b0 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2252 [inline] slab_free mm/slub.c:4473 [inline] kfree+0x149/0x360 mm/slub.c:4594 skb_kfree_head net/core/skbuff.c:1084 [inline] skb_free_head net/core/skbuff.c:1096 [inline] skb_release_data+0x676/0x880 net/core/skbuff.c:1123 skb_release_all net/core/skbuff.c:1188 [inline] __kfree_skb net/core/skbuff.c:1202 [inline] consume_skb+0xb1/0x160 net/core/skbuff.c:1426 nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline] nsim_dev_trap_report_work+0x765/0xaa0 drivers/net/netdevsim/dev.c:850 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390 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> vkms_vblank_simulate: vblank timer overrun --- 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
