Hello, syzbot found the following issue on: HEAD commit: 715abedee4cd Add linux-next specific files for 20230515 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=16cc8ced280000 kernel config: https://syzkaller.appspot.com/x/.config?x=6a2745d066dda0ec dashboard link: https://syzkaller.appspot.com/bug?extid=a694851c6ab28cbcfb9c compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=146e7c35280000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12ea7ffe280000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/d4d1d06b34b8/disk-715abede.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/3ef33a86fdc8/vmlinux-715abede.xz kernel image: https://storage.googleapis.com/syzbot-assets/e0006b413ed1/bzImage-715abede.xz mounted in repro: https://storage.googleapis.com/syzbot-assets/8a4c583d7fb5/mount_0.gz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+a694851c6ab28cbcfb9c@xxxxxxxxxxxxxxxxxxxxxxxxx INFO: task syz-executor274:6164 blocked for more than 143 seconds. Not tainted 6.4.0-rc2-next-20230515-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor274 state:D stack:24920 pid:6164 ppid:5041 flags:0x00004004 Call Trace: <TASK> context_switch kernel/sched/core.c:5343 [inline] __schedule+0x1d15/0x5790 kernel/sched/core.c:6669 schedule+0xde/0x1a0 kernel/sched/core.c:6745 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6804 rwsem_down_write_slowpath+0x3e2/0x1220 kernel/locking/rwsem.c:1178 __down_write_common kernel/locking/rwsem.c:1306 [inline] __down_write kernel/locking/rwsem.c:1315 [inline] down_write+0x1d2/0x200 kernel/locking/rwsem.c:1574 inode_lock include/linux/fs.h:775 [inline] btrfs_inode_lock+0x7e/0xf0 fs/btrfs/inode.c:377 btrfs_sync_file+0x455/0x12d0 fs/btrfs/file.c:1808 vfs_fsync_range+0x13e/0x230 fs/sync.c:188 generic_write_sync include/linux/fs.h:2469 [inline] btrfs_do_write_iter+0x520/0x1210 fs/btrfs/file.c:1680 call_write_iter include/linux/fs.h:1868 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x945/0xd50 fs/read_write.c:584 ksys_write+0x12b/0x250 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f0de39026c9 RSP: 002b:00007f0de38a5208 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f0de3984788 RCX: 00007f0de39026c9 RDX: 0000000000000128 RSI: 0000000020004400 RDI: 0000000000000006 RBP: 00007f0de3984780 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f0de398478c R13: 00007fffb0c5635f R14: 00007f0de38a5300 R15: 0000000000022000 </TASK> INFO: task syz-executor274:6181 blocked for more than 143 seconds. Not tainted 6.4.0-rc2-next-20230515-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor274 state:D stack:26416 pid:6181 ppid:5041 flags:0x00004004 Call Trace: <TASK> context_switch kernel/sched/core.c:5343 [inline] __schedule+0x1d15/0x5790 kernel/sched/core.c:6669 schedule+0xde/0x1a0 kernel/sched/core.c:6745 wait_on_state fs/btrfs/extent-io-tree.c:707 [inline] wait_extent_bit+0x56e/0x670 fs/btrfs/extent-io-tree.c:751 lock_extent+0x120/0x1c0 fs/btrfs/extent-io-tree.c:1742 btrfs_page_mkwrite+0x652/0x11a0 fs/btrfs/inode.c:8336 do_page_mkwrite+0x1a1/0x690 mm/memory.c:2934 wp_page_shared mm/memory.c:3283 [inline] do_wp_page+0x356/0x34e0 mm/memory.c:3365 handle_pte_fault mm/memory.c:4967 [inline] __handle_mm_fault+0x1635/0x4170 mm/memory.c:5092 handle_mm_fault+0x2af/0x9f0 mm/memory.c:5246 do_user_addr_fault+0x51a/0x1210 arch/x86/mm/fault.c:1440 handle_page_fault arch/x86/mm/fault.c:1534 [inline] exc_page_fault+0x98/0x170 arch/x86/mm/fault.c:1590 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570 RIP: 0010:rep_movs_alternative+0x33/0xb0 arch/x86/lib/copy_user_64.S:56 Code: 46 83 f9 08 73 21 85 c9 74 0f 8a 06 88 07 48 ff c7 48 ff c6 48 ff c9 75 f1 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 RSP: 0018:ffffc9000becf728 EFLAGS: 00050206 RAX: 0000000000000000 RBX: 0000000000000038 RCX: 0000000000000038 RDX: fffff520017d9efb RSI: ffffc9000becf7a0 RDI: 0000000020000120 RBP: 0000000020000120 R08: 0000000000000000 R09: fffff520017d9efa R10: ffffc9000becf7d7 R11: 0000000000000001 R12: ffffc9000becf7a0 R13: 0000000020000158 R14: 0000000000000000 R15: ffffc9000becf7a0 copy_user_generic arch/x86/include/asm/uaccess_64.h:112 [inline] raw_copy_to_user arch/x86/include/asm/uaccess_64.h:133 [inline] _copy_to_user lib/usercopy.c:41 [inline] _copy_to_user+0xab/0xc0 lib/usercopy.c:34 copy_to_user include/linux/uaccess.h:191 [inline] fiemap_fill_next_extent+0x217/0x370 fs/ioctl.c:144 emit_fiemap_extent+0x18e/0x380 fs/btrfs/extent_io.c:2616 fiemap_process_hole+0x516/0x610 fs/btrfs/extent_io.c:2874 extent_fiemap+0x123b/0x1950 fs/btrfs/extent_io.c:3089 btrfs_fiemap+0xe9/0x170 fs/btrfs/inode.c:8008 ioctl_fiemap fs/ioctl.c:219 [inline] do_vfs_ioctl+0x466/0x1670 fs/ioctl.c:810 __do_sys_ioctl fs/ioctl.c:868 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x10c/0x210 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f0de39026c9 RSP: 002b:00007f0ddc484208 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f0de3984798 RCX: 00007f0de39026c9 RDX: 0000000020000100 RSI: 00000000c020660b RDI: 0000000000000005 RBP: 00007f0de3984790 R08: 00007f0ddc484700 R09: 0000000000000000 R10: 00007f0ddc484700 R11: 0000000000000246 R12: 00007f0de398479c R13: 00007fffb0c5635f R14: 00007f0ddc484300 R15: 0000000000022000 </TASK> Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/13: #0: ffffffff8c798530 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:522 1 lock held by rcu_tasks_trace/14: #0: ffffffff8c798230 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:522 1 lock held by khungtaskd/28: #0: ffffffff8c799140 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x390 kernel/locking/lockdep.c:6559 2 locks held by getty/4759: #0: ffff888028dba098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x26/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900015902f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xef4/0x13e0 drivers/tty/n_tty.c:2176 3 locks held by syz-executor274/6164: #0: ffff888027b554e8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe7/0x100 fs/file.c:1047 #1: ffff88807cee8460 (sb_writers#10){.+.+}-{0:0}, at: ksys_write+0x12b/0x250 fs/read_write.c:637 #2: ffff888075278590 (&sb->s_type->i_mutex_key#15){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline] #2: ffff888075278590 (&sb->s_type->i_mutex_key#15){++++}-{3:3}, at: btrfs_inode_lock+0x7e/0xf0 fs/btrfs/inode.c:377 4 locks held by syz-executor274/6181: #0: ffff888075278590 (&sb->s_type->i_mutex_key#15){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:785 [inline] #0: ffff888075278590 (&sb->s_type->i_mutex_key#15){++++}-{3:3}, at: btrfs_inode_lock+0xd8/0xf0 fs/btrfs/inode.c:369 #1: ffff88807f081368 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:161 [inline] #1: ffff88807f081368 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault+0x448/0x1210 arch/x86/mm/fault.c:1381 #2: ffff88807cee8558 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x1a1/0x690 mm/memory.c:2934 #3: ffff888075278418 (&ei->i_mmap_lock){++++}-{3:3}, at: btrfs_page_mkwrite+0x6eb/0x11a0 fs/btrfs/inode.c:8325 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.4.0-rc2-next-20230515-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 nmi_cpu_backtrace+0x29c/0x350 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x2a4/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xe16/0x1090 kernel/hung_task.c:379 kthread+0x344/0x440 kernel/kthread.c:379 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline] NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x40/0x50 drivers/acpi/processor_idle.c:112 --- 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 bug is already fixed, let syzbot know by replying with: #syz fix: exact-commit-title If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. If you want to change bug's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the bug is a duplicate of another bug, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
