bisecting fixing commit since 6500aa436df40a46998f7a56a32e8199a3513e6d building syzkaller on 442206d76b974cca2d83ec763d4cf5ee829eb7d6 testing commit 6500aa436df40a46998f7a56a32e8199a3513e6d compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 2466bdafab35954ed7ca2b98b12789be6da9973aece758db25d56561f80c91ca all runs: crashed: INFO: task hung in __fuse_request_send testing current HEAD 53bd76690e27f37c9df221a651a52cea04214da9 testing commit 53bd76690e27f37c9df221a651a52cea04214da9 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: af39fea1cb6ac68b023ff9b4df62c60ea786d04033aa589c46209d77f4590746 all runs: crashed: INFO: task hung in __fuse_request_send revisions tested: 2, total time: 33m7.57818242s (build: 17m51.367159856s, test: 14m29.578635121s) the crash still happens on HEAD commit msg: Linux 4.19.200 crash: INFO: task hung in __fuse_request_send IPv6: ADDRCONF(NETDEV_UP): vxcan1: link is not ready 8021q: adding VLAN 0 to HW filter on device batadv0 IPv6: ADDRCONF(NETDEV_UP): vxcan1: link is not ready 8021q: adding VLAN 0 to HW filter on device batadv0 INFO: task syz-executor.0:6543 blocked for more than 140 seconds. Not tainted 4.19.200-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D27448 6543 5641 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0xdb5/0x1d40 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 request_wait_answer+0x2fe/0x620 fs/fuse/dev.c:485 __fuse_request_send+0xff/0x190 fs/fuse/dev.c:505 fuse_request_send+0x41/0x80 fs/fuse/dev.c:518 fuse_simple_request+0x2b4/0x610 fs/fuse/dev.c:576 fuse_lookup_name+0x244/0x590 fs/fuse/dir.c:330 fuse_lookup+0xf3/0x3b0 fs/fuse/dir.c:368 __lookup_slow+0x216/0x400 fs/namei.c:1672 lookup_slow+0x51/0x70 fs/namei.c:1689 walk_component+0x697/0x11b0 fs/namei.c:1811 lookup_last fs/namei.c:2274 [inline] path_lookupat.isra.43+0x180/0x850 fs/namei.c:2319 filename_lookup.part.57+0x160/0x360 fs/namei.c:2349 filename_lookup fs/namei.c:2342 [inline] user_path_at_empty+0x39/0x40 fs/namei.c:2609 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0xbe/0x150 fs/stat.c:185 vfs_stat include/linux/fs.h:3132 [inline] __do_sys_newstat+0x85/0xe0 fs/stat.c:337 __se_sys_newstat fs/stat.c:333 [inline] __x64_sys_newstat+0x4f/0x70 fs/stat.c:333 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x460b89 Code: Bad RIP value. RSP: 002b:00007f264a0b41a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 000000000052bf00 RCX: 0000000000460b89 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000580 RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004f7168 R14: 00000000004c16e3 R15: 00007f264a0b46bc INFO: task syz-executor.0:6548 blocked for more than 140 seconds. Not tainted 4.19.200-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29608 6548 5641 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0xdb5/0x1d40 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x5c7/0xbe0 kernel/locking/rwsem-xadd.c:618 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:748 [inline] lock_mount+0x82/0x290 fs/namespace.c:2039 do_add_mount+0x22/0x310 fs/namespace.c:2416 do_new_mount fs/namespace.c:2483 [inline] do_mount+0x1290/0x2410 fs/namespace.c:2799 ksys_mount+0xb1/0xd0 fs/namespace.c:3015 __do_sys_mount fs/namespace.c:3029 [inline] __se_sys_mount fs/namespace.c:3026 [inline] __x64_sys_mount+0xb9/0x150 fs/namespace.c:3026 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x460b89 Code: Bad RIP value. RSP: 002b:00007f264a0931a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 000000000052bfa8 RCX: 0000000000460b89 RDX: 0000000020000000 RSI: 0000000020000180 RDI: 0000000000000000 RBP: 0000000000000005 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004f25c0 R14: 00000000004b1a00 R15: 00007f264a0936bc INFO: task syz-executor.0:6549 blocked for more than 140 seconds. Not tainted 4.19.200-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D27864 6549 5641 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0xdb5/0x1d40 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x5c7/0xbe0 kernel/locking/rwsem-xadd.c:618 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:748 [inline] fuse_reverse_inval_entry+0x9a/0x5d0 fs/fuse/dir.c:987 fuse_notify_delete fs/fuse/dev.c:1585 [inline] fuse_notify fs/fuse/dev.c:1819 [inline] fuse_dev_do_write+0xba9/0x2400 fs/fuse/dev.c:1894 fuse_dev_write+0x12a/0x1b0 fs/fuse/dev.c:1978 call_write_iter include/linux/fs.h:1821 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x443/0x890 fs/read_write.c:487 vfs_write+0x150/0x4d0 fs/read_write.c:549 ksys_write+0x103/0x260 fs/read_write.c:599 __do_sys_write fs/read_write.c:611 [inline] __se_sys_write fs/read_write.c:608 [inline] __x64_sys_write+0x6e/0xb0 fs/read_write.c:608 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x460b89 Code: Bad RIP value. RSP: 002b:00007f264a0721a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000052c050 RCX: 0000000000460b89 RDX: 000000000000002e RSI: 0000000020000000 RDI: 0000000000000003 RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004f8200 R14: 00000000004b4d98 R15: 00007f264a0726bc INFO: task syz-executor.0:6590 blocked for more than 140 seconds. Not tainted 4.19.200-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D27288 6590 5641 0x00000006 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0xdb5/0x1d40 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x5c7/0xbe0 kernel/locking/rwsem-xadd.c:618 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:748 [inline] lock_mount+0x82/0x290 fs/namespace.c:2039 do_add_mount+0x22/0x310 fs/namespace.c:2416 do_new_mount fs/namespace.c:2483 [inline] do_mount+0x1290/0x2410 fs/namespace.c:2799 ksys_mount+0xb1/0xd0 fs/namespace.c:3015 __do_sys_mount fs/namespace.c:3029 [inline] __se_sys_mount fs/namespace.c:3026 [inline] __x64_sys_mount+0xb9/0x150 fs/namespace.c:3026 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x460b89 Code: Bad RIP value. RSP: 002b:00007f264a0301a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 000000000052c1a0 RCX: 0000000000460b89 RDX: 0000000020000240 RSI: 0000000020000200 RDI: 0000000000000000 RBP: 0000000000000005 R08: 0000000020000400 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004f2680 R14: 00000000004b19d4 R15: 00007f264a0306bc INFO: task syz-executor.0:6591 blocked for more than 140 seconds. Not tainted 4.19.200-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29176 6591 5641 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0xdb5/0x1d40 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline] rwsem_down_read_failed+0x21c/0x3e0 kernel/locking/rwsem-xadd.c:309 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94 __down_read arch/x86/include/asm/rwsem.h:83 [inline] down_read+0x49/0xb0 kernel/locking/rwsem.c:26 inode_lock_shared include/linux/fs.h:758 [inline] lookup_slow+0x43/0x70 fs/namei.c:1688 walk_component+0x697/0x11b0 fs/namei.c:1811 lookup_last fs/namei.c:2274 [inline] path_lookupat.isra.43+0x180/0x850 fs/namei.c:2319 filename_lookup.part.57+0x160/0x360 fs/namei.c:2349 filename_lookup fs/namei.c:2342 [inline] user_path_at_empty+0x39/0x40 fs/namei.c:2609 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0xbe/0x150 fs/stat.c:185 vfs_stat include/linux/fs.h:3132 [inline] __do_sys_newstat+0x85/0xe0 fs/stat.c:337 __se_sys_newstat fs/stat.c:333 [inline] __x64_sys_newstat+0x4f/0x70 fs/stat.c:333 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x460b89 Code: Bad RIP value. RSP: 002b:00007f264a00f1a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 000000000052c248 RCX: 0000000000460b89 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000580 RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004f7168 R14: 00000000004c16e3 R15: 00007f264a00f6bc INFO: task syz-executor.1:6551 blocked for more than 140 seconds. Not tainted 4.19.200-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D27816 6551 5649 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0xdb5/0x1d40 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 request_wait_answer+0x2fe/0x620 fs/fuse/dev.c:485 __fuse_request_send+0xff/0x190 fs/fuse/dev.c:505 fuse_request_send+0x41/0x80 fs/fuse/dev.c:518 fuse_simple_request+0x2b4/0x610 fs/fuse/dev.c:576 fuse_lookup_name+0x244/0x590 fs/fuse/dir.c:330 fuse_lookup+0xf3/0x3b0 fs/fuse/dir.c:368 __lookup_slow+0x216/0x400 fs/namei.c:1672 lookup_slow+0x51/0x70 fs/namei.c:1689 walk_component+0x697/0x11b0 fs/namei.c:1811 lookup_last fs/namei.c:2274 [inline] path_lookupat.isra.43+0x180/0x850 fs/namei.c:2319 filename_lookup.part.57+0x160/0x360 fs/namei.c:2349 filename_lookup fs/namei.c:2342 [inline] user_path_at_empty+0x39/0x40 fs/namei.c:2609 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0xbe/0x150 fs/stat.c:185 vfs_stat include/linux/fs.h:3132 [inline] __do_sys_newstat+0x85/0xe0 fs/stat.c:337 __se_sys_newstat fs/stat.c:333 [inline] __x64_sys_newstat+0x4f/0x70 fs/stat.c:333 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x460b89 Code: Bad RIP value. RSP: 002b:00007f28385bf1a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 000000000052bf00 RCX: 0000000000460b89 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000580 RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004f7168 R14: 00000000004c16e3 R15: 00007f28385bf6bc INFO: task syz-executor.1:6561 blocked for more than 140 seconds. Not tainted 4.19.200-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28920 6561 5649 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0xdb5/0x1d40 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x5c7/0xbe0 kernel/locking/rwsem-xadd.c:618 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:748 [inline] fuse_reverse_inval_entry+0x9a/0x5d0 fs/fuse/dir.c:987 fuse_notify_delete fs/fuse/dev.c:1585 [inline] fuse_notify fs/fuse/dev.c:1819 [inline] fuse_dev_do_write+0xba9/0x2400 fs/fuse/dev.c:1894 fuse_dev_write+0x12a/0x1b0 fs/fuse/dev.c:1978 call_write_iter include/linux/fs.h:1821 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x443/0x890 fs/read_write.c:487 vfs_write+0x150/0x4d0 fs/read_write.c:549 ksys_write+0x103/0x260 fs/read_write.c:599 __do_sys_write fs/read_write.c:611 [inline] __se_sys_write fs/read_write.c:608 [inline] __x64_sys_write+0x6e/0xb0 fs/read_write.c:608 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x460b89 Code: Bad RIP value. RSP: 002b:00007f283859e1a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000052bfa8 RCX: 0000000000460b89 RDX: 000000000000002e RSI: 0000000020000000 RDI: 0000000000000003 RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004f8200 R14: 00000000004b4d98 R15: 00007f283859e6bc INFO: task syz-executor.1:6563 blocked for more than 140 seconds. Not tainted 4.19.200-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28824 6563 5649 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0xdb5/0x1d40 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x5c7/0xbe0 kernel/locking/rwsem-xadd.c:618 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:748 [inline] lock_mount+0x82/0x290 fs/namespace.c:2039 do_add_mount+0x22/0x310 fs/namespace.c:2416 do_new_mount fs/namespace.c:2483 [inline] do_mount+0x1290/0x2410 fs/namespace.c:2799 ksys_mount+0xb1/0xd0 fs/namespace.c:3015 __do_sys_mount fs/namespace.c:3029 [inline] __se_sys_mount fs/namespace.c:3026 [inline] __x64_sys_mount+0xb9/0x150 fs/namespace.c:3026 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x460b89 Code: Bad RIP value. RSP: 002b:00007f283857d1a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 000000000052c050 RCX: 0000000000460b89 RDX: 0000000020000000 RSI: 0000000020000180 RDI: 0000000000000000 RBP: 0000000000000005 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004f25c0 R14: 00000000004b1a00 R15: 00007f283857d6bc INFO: task syz-executor.1:6595 blocked for more than 140 seconds. Not tainted 4.19.200-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D29176 6595 5649 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0xdb5/0x1d40 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline] rwsem_down_read_failed+0x21c/0x3e0 kernel/locking/rwsem-xadd.c:309 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94 __down_read arch/x86/include/asm/rwsem.h:83 [inline] down_read+0x49/0xb0 kernel/locking/rwsem.c:26 inode_lock_shared include/linux/fs.h:758 [inline] lookup_slow+0x43/0x70 fs/namei.c:1688 walk_component+0x697/0x11b0 fs/namei.c:1811 lookup_last fs/namei.c:2274 [inline] path_lookupat.isra.43+0x180/0x850 fs/namei.c:2319 filename_lookup.part.57+0x160/0x360 fs/namei.c:2349 filename_lookup fs/namei.c:2342 [inline] user_path_at_empty+0x39/0x40 fs/namei.c:2609 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0xbe/0x150 fs/stat.c:185 vfs_stat include/linux/fs.h:3132 [inline] __do_sys_newstat+0x85/0xe0 fs/stat.c:337 __se_sys_newstat fs/stat.c:333 [inline] __x64_sys_newstat+0x4f/0x70 fs/stat.c:333 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x460b89 Code: Bad RIP value. RSP: 002b:00007f283855c1a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 000000000052c0f8 RCX: 0000000000460b89 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000580 RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004f7168 R14: 00000000004c16e3 R15: 00007f283855c6bc INFO: task syz-executor.1:6596 blocked for more than 140 seconds. Not tainted 4.19.200-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D27960 6596 5649 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0xdb5/0x1d40 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x5c7/0xbe0 kernel/locking/rwsem-xadd.c:618 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:748 [inline] lock_mount+0x82/0x290 fs/namespace.c:2039 do_add_mount+0x22/0x310 fs/namespace.c:2416 do_new_mount fs/namespace.c:2483 [inline] do_mount+0x1290/0x2410 fs/namespace.c:2799 ksys_mount+0xb1/0xd0 fs/namespace.c:3015 __do_sys_mount fs/namespace.c:3029 [inline] __se_sys_mount fs/namespace.c:3026 [inline] __x64_sys_mount+0xb9/0x150 fs/namespace.c:3026 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x460b89 Code: Bad RIP value. RSP: 002b:00007f283853b1a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 000000000052c1a0 RCX: 0000000000460b89 RDX: 0000000020000240 RSI: 0000000020000200 RDI: 0000000000000000 RBP: 0000000000000005 R08: 0000000020000400 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000004f2680 R14: 00000000004b19d4 R15: 00007f283853b6bc Showing all locks held in the system: 1 lock held by khungtaskd/1042: #0: 0000000053bde36f (rcu_read_lock){....}, at: debug_show_all_locks+0x5b/0x27a kernel/locking/lockdep.c:4443 2 locks held by syz-executor.0/6543: #0: 00000000b423256c (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:758 [inline] #0: 00000000b423256c (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 #1: 0000000001ad3573 (&fi->mutex){+.+.}, at: fuse_lock_inode+0x9a/0xc0 fs/fuse/inode.c:365 1 lock held by syz-executor.0/6548: #0: 00000000b423256c (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline] #0: 00000000b423256c (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 2 locks held by syz-executor.0/6549: #0: 00000000144f2eb8 (&fc->killsb){.+.+}, at: fuse_notify_delete fs/fuse/dev.c:1582 [inline] #0: 00000000144f2eb8 (&fc->killsb){.+.+}, at: fuse_notify fs/fuse/dev.c:1819 [inline] #0: 00000000144f2eb8 (&fc->killsb){.+.+}, at: fuse_dev_do_write+0x19e0/0x2400 fs/fuse/dev.c:1894 #1: 00000000b423256c (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline] #1: 00000000b423256c (&type->i_mutex_dir_key#8){++++}, at: fuse_reverse_inval_entry+0x9a/0x5d0 fs/fuse/dir.c:987 1 lock held by syz-executor.0/6590: #0: 00000000b423256c (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline] #0: 00000000b423256c (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 1 lock held by syz-executor.0/6591: #0: 00000000b423256c (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:758 [inline] #0: 00000000b423256c (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 2 locks held by syz-executor.1/6551: #0: 0000000044fc0c5d (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:758 [inline] #0: 0000000044fc0c5d (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 #1: 00000000b959866c (&fi->mutex){+.+.}, at: fuse_lock_inode+0x9a/0xc0 fs/fuse/inode.c:365 2 locks held by syz-executor.1/6561: #0: 0000000019d4ce24 (&fc->killsb){.+.+}, at: fuse_notify_delete fs/fuse/dev.c:1582 [inline] #0: 0000000019d4ce24 (&fc->killsb){.+.+}, at: fuse_notify fs/fuse/dev.c:1819 [inline] #0: 0000000019d4ce24 (&fc->killsb){.+.+}, at: fuse_dev_do_write+0x19e0/0x2400 fs/fuse/dev.c:1894 #1: 0000000044fc0c5d (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline] #1: 0000000044fc0c5d (&type->i_mutex_dir_key#8){++++}, at: fuse_reverse_inval_entry+0x9a/0x5d0 fs/fuse/dir.c:987 1 lock held by syz-executor.1/6563: #0: 0000000044fc0c5d (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline] #0: 0000000044fc0c5d (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 1 lock held by syz-executor.1/6595: #0: 0000000044fc0c5d (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:758 [inline] #0: 0000000044fc0c5d (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 1 lock held by syz-executor.1/6596: #0: 0000000044fc0c5d (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline] #0: 0000000044fc0c5d (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 2 locks held by syz-executor.3/6557: #0: 00000000a4917e8f (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:758 [inline] #0: 00000000a4917e8f (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 #1: 000000004ff2e3c7 (&fi->mutex){+.+.}, at: fuse_lock_inode+0x9a/0xc0 fs/fuse/inode.c:365 2 locks held by syz-executor.3/6562: #0: 000000006b0706cc (&fc->killsb){.+.+}, at: fuse_notify_delete fs/fuse/dev.c:1582 [inline] #0: 000000006b0706cc (&fc->killsb){.+.+}, at: fuse_notify fs/fuse/dev.c:1819 [inline] #0: 000000006b0706cc (&fc->killsb){.+.+}, at: fuse_dev_do_write+0x19e0/0x2400 fs/fuse/dev.c:1894 #1: 00000000a4917e8f (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline] #1: 00000000a4917e8f (&type->i_mutex_dir_key#8){++++}, at: fuse_reverse_inval_entry+0x9a/0x5d0 fs/fuse/dir.c:987 1 lock held by syz-executor.3/6564: #0: 00000000a4917e8f (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline] #0: 00000000a4917e8f (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 1 lock held by syz-executor.3/6600: #0: 00000000a4917e8f (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline] #0: 00000000a4917e8f (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 1 lock held by syz-executor.3/6601: #0: 00000000a4917e8f (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:758 [inline] #0: 00000000a4917e8f (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 2 locks held by syz-executor.5/6566: #0: 000000006876100d (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:758 [inline] #0: 000000006876100d (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 #1: 00000000309f06f1 (&fi->mutex){+.+.}, at: fuse_lock_inode+0x9a/0xc0 fs/fuse/inode.c:365 2 locks held by syz-executor.5/6571: #0: 00000000e6163e3f (&fc->killsb){.+.+}, at: fuse_notify_delete fs/fuse/dev.c:1582 [inline] #0: 00000000e6163e3f (&fc->killsb){.+.+}, at: fuse_notify fs/fuse/dev.c:1819 [inline] #0: 00000000e6163e3f (&fc->killsb){.+.+}, at: fuse_dev_do_write+0x19e0/0x2400 fs/fuse/dev.c:1894 #1: 000000006876100d (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline] #1: 000000006876100d (&type->i_mutex_dir_key#8){++++}, at: fuse_reverse_inval_entry+0x9a/0x5d0 fs/fuse/dir.c:987 1 lock held by syz-executor.5/6579: #0: 000000006876100d (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline] #0: 000000006876100d (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 1 lock held by syz-executor.5/6609: #0: 000000006876100d (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline] #0: 000000006876100d (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 1 lock held by syz-executor.5/6610: #0: 000000006876100d (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:758 [inline] #0: 000000006876100d (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 2 locks held by syz-executor.2/6575: #0: 000000000fcd9e15 (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:758 [inline] #0: 000000000fcd9e15 (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 #1: 00000000ad55a652 (&fi->mutex){+.+.}, at: fuse_lock_inode+0x9a/0xc0 fs/fuse/inode.c:365 1 lock held by syz-executor.2/6585: #0: 000000000fcd9e15 (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline] #0: 000000000fcd9e15 (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 2 locks held by syz-executor.2/6587: #0: 00000000046ff2b0 (&fc->killsb){.+.+}, at: fuse_notify_delete fs/fuse/dev.c:1582 [inline] #0: 00000000046ff2b0 (&fc->killsb){.+.+}, at: fuse_notify fs/fuse/dev.c:1819 [inline] #0: 00000000046ff2b0 (&fc->killsb){.+.+}, at: fuse_dev_do_write+0x19e0/0x2400 fs/fuse/dev.c:1894 #1: 000000000fcd9e15 (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline] #1: 000000000fcd9e15 (&type->i_mutex_dir_key#8){++++}, at: fuse_reverse_inval_entry+0x9a/0x5d0 fs/fuse/dir.c:987 1 lock held by syz-executor.2/6615: #0: 000000000fcd9e15 (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline] #0: 000000000fcd9e15 (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 1 lock held by syz-executor.2/6616: #0: 000000000fcd9e15 (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:758 [inline] #0: 000000000fcd9e15 (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 2 locks held by syz-executor.4/6580: #0: 000000005f93044e (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:758 [inline] #0: 000000005f93044e (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 #1: 000000000749effb (&fi->mutex){+.+.}, at: fuse_lock_inode+0x9a/0xc0 fs/fuse/inode.c:365 1 lock held by syz-executor.4/6586: #0: 000000005f93044e (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline] #0: 000000005f93044e (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 2 locks held by syz-executor.4/6588: #0: 0000000056bff5f6 (&fc->killsb){.+.+}, at: fuse_notify_delete fs/fuse/dev.c:1582 [inline] #0: 0000000056bff5f6 (&fc->killsb){.+.+}, at: fuse_notify fs/fuse/dev.c:1819 [inline] #0: 0000000056bff5f6 (&fc->killsb){.+.+}, at: fuse_dev_do_write+0x19e0/0x2400 fs/fuse/dev.c:1894 #1: 000000005f93044e (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline] #1: 000000005f93044e (&type->i_mutex_dir_key#8){++++}, at: fuse_reverse_inval_entry+0x9a/0x5d0 fs/fuse/dir.c:987 1 lock held by syz-executor.4/6621: #0: 000000005f93044e (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline] #0: 000000005f93044e (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 1 lock held by syz-executor.4/6622: #0: 000000005f93044e (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:758 [inline] #0: 000000005f93044e (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1042 Comm: khungtaskd Not tainted 4.19.200-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x123/0x171 lib/dump_stack.c:118 nmi_cpu_backtrace.cold.4+0x3e/0x76 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0xe6/0x120 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x5c3/0xb40 kernel/hung_task.c:287 kthread+0x347/0x410 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 skipped: idling at native_safe_halt+0x12/0x20 arch/x86/include/asm/irqflags.h:60