bisecting fixing commit since bc2bccef19ee4353d759a12950088b968b5c6618 building syzkaller on 0a8d1a965a65f2d6cc93d1180443f5ad658919b1 testing commit bc2bccef19ee4353d759a12950088b968b5c6618 with gcc (GCC) 8.1.0 kernel signature: 68993e6cec80ea7eea4c6781d3335f8ff63ecb7498a120d75101fbe4c6f94a65 all runs: crashed: INFO: task hung in __fuse_request_send testing current HEAD 050272a0423e68207fd2367831ae610680129062 testing commit 050272a0423e68207fd2367831ae610680129062 with gcc (GCC) 8.1.0 kernel signature: a0008b0bc6793f135e1e5b217a85de854179a180de7a7979cc3b579aaee20906 all runs: crashed: INFO: task hung in __fuse_request_send revisions tested: 2, total time: 32m34.366755303s (build: 17m24.603709603s, test: 13m57.27889543s) the crash still happens on HEAD commit msg: Linux 4.14.177 crash: INFO: task hung in __fuse_request_send IPv6: ADDRCONF(NETDEV_CHANGE): hsr0: link becomes 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.5:6973 blocked for more than 140 seconds. Not tainted 4.14.177-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D27568 6973 6105 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x780/0x1d20 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 request_wait_answer+0x2e3/0x600 fs/fuse/dev.c:478 __fuse_request_send+0xff/0x190 fs/fuse/dev.c:498 fuse_request_send+0x48/0x60 fs/fuse/dev.c:511 fuse_simple_request+0x2b4/0x610 fs/fuse/dev.c:569 fuse_lookup_name+0x238/0x570 fs/fuse/dir.c:330 fuse_lookup+0xe4/0x380 fs/fuse/dir.c:368 lookup_slow+0x20f/0x3f0 fs/namei.c:1696 walk_component+0x680/0x21a0 fs/namei.c:1825 lookup_last fs/namei.c:2293 [inline] path_lookupat.isra.40+0x17f/0x810 fs/namei.c:2343 filename_lookup.part.53+0x15b/0x340 fs/namei.c:2377 filename_lookup fs/namei.c:2370 [inline] user_path_at_empty+0x39/0x40 fs/namei.c:2631 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0xb6/0x130 fs/stat.c:185 vfs_stat include/linux/fs.h:3061 [inline] SYSC_newstat+0x7d/0xc0 fs/stat.c:337 SyS_newstat+0x9/0x10 fs/stat.c:333 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x459519 RSP: 002b:00007f8a99cf8c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000459519 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000580 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8a99cf96d4 R13: 00000000004e585b R14: 00000000004deb88 R15: 00000000ffffffff INFO: task syz-executor.5:6977 blocked for more than 140 seconds. Not tainted 4.14.177-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D29120 6977 6105 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x780/0x1d20 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:588 [inline] rwsem_down_write_failed+0x54f/0xb50 kernel/locking/rwsem-xadd.c:617 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105 __down_write arch/x86/include/asm/rwsem.h:126 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:56 inode_lock include/linux/fs.h:719 [inline] lock_mount+0x82/0x290 fs/namespace.c:2119 do_add_mount+0x22/0x310 fs/namespace.c:2496 do_new_mount fs/namespace.c:2563 [inline] do_mount+0x12cf/0x26a0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xb8/0xd0 fs/namespace.c:3072 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x459519 RSP: 002b:00007f8a99cd7c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000459519 RDX: 0000000020000000 RSI: 0000000020000180 RDI: 0000000000000000 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 00007f8a99cd86d4 R13: 00000000004c595e R14: 00000000004d9fe0 R15: 00000000ffffffff INFO: task syz-executor.5:6978 blocked for more than 140 seconds. Not tainted 4.14.177-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28768 6978 6105 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x780/0x1d20 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:588 [inline] rwsem_down_write_failed+0x54f/0xb50 kernel/locking/rwsem-xadd.c:617 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105 __down_write arch/x86/include/asm/rwsem.h:126 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:56 inode_lock include/linux/fs.h:719 [inline] fuse_reverse_inval_entry+0x92/0x5c0 fs/fuse/dir.c:972 fuse_notify_delete fs/fuse/dev.c:1562 [inline] fuse_notify fs/fuse/dev.c:1796 [inline] fuse_dev_do_write+0xe58/0x2310 fs/fuse/dev.c:1871 fuse_dev_write+0x11a/0x180 fs/fuse/dev.c:1955 call_write_iter include/linux/fs.h:1778 [inline] new_sync_write fs/read_write.c:469 [inline] __vfs_write+0x413/0x840 fs/read_write.c:482 vfs_write+0x150/0x4f0 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0x100/0x250 fs/read_write.c:582 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x459519 RSP: 002b:00007f8a99cb6c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459519 RDX: 000000000000002e RSI: 0000000020000000 RDI: 0000000000000003 RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8a99cb76d4 R13: 00000000004c8d0e R14: 00000000004dfc50 R15: 00000000ffffffff INFO: task syz-executor.5:6991 blocked for more than 140 seconds. Not tainted 4.14.177-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D27936 6991 6105 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x780/0x1d20 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:588 [inline] rwsem_down_write_failed+0x54f/0xb50 kernel/locking/rwsem-xadd.c:617 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105 __down_write arch/x86/include/asm/rwsem.h:126 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:56 inode_lock include/linux/fs.h:719 [inline] lock_mount+0x82/0x290 fs/namespace.c:2119 do_add_mount+0x22/0x310 fs/namespace.c:2496 do_new_mount fs/namespace.c:2563 [inline] do_mount+0x12cf/0x26a0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xb8/0xd0 fs/namespace.c:3072 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x459519 RSP: 002b:00007f8a99c95c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000459519 RDX: 0000000020000240 RSI: 0000000020000200 RDI: 0000000000000000 RBP: 000000000075c118 R08: 0000000020000400 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8a99c966d4 R13: 00000000004c5932 R14: 00000000004da0a0 R15: 00000000ffffffff INFO: task syz-executor.5:6992 blocked for more than 140 seconds. Not tainted 4.14.177-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28920 6992 6105 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x780/0x1d20 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline] rwsem_down_read_failed+0x1fc/0x390 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:66 [inline] down_read+0x49/0xb0 kernel/locking/rwsem.c:26 inode_lock_shared include/linux/fs.h:729 [inline] lookup_slow+0x123/0x3f0 fs/namei.c:1674 walk_component+0x680/0x21a0 fs/namei.c:1825 lookup_last fs/namei.c:2293 [inline] path_lookupat.isra.40+0x17f/0x810 fs/namei.c:2343 filename_lookup.part.53+0x15b/0x340 fs/namei.c:2377 filename_lookup fs/namei.c:2370 [inline] user_path_at_empty+0x39/0x40 fs/namei.c:2631 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0xb6/0x130 fs/stat.c:185 vfs_stat include/linux/fs.h:3061 [inline] SYSC_newstat+0x7d/0xc0 fs/stat.c:337 SyS_newstat+0x9/0x10 fs/stat.c:333 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x459519 RSP: 002b:00007f8a99c74c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000459519 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000580 RBP: 000000000075c1c0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f8a99c756d4 R13: 00000000004e585b R14: 00000000004deb88 R15: 00000000ffffffff INFO: task syz-executor.1:7010 blocked for more than 140 seconds. Not tainted 4.14.177-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D27520 7010 6103 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x780/0x1d20 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 request_wait_answer+0x2e3/0x600 fs/fuse/dev.c:478 __fuse_request_send+0xff/0x190 fs/fuse/dev.c:498 fuse_request_send+0x48/0x60 fs/fuse/dev.c:511 fuse_simple_request+0x2b4/0x610 fs/fuse/dev.c:569 fuse_lookup_name+0x238/0x570 fs/fuse/dir.c:330 fuse_lookup+0xe4/0x380 fs/fuse/dir.c:368 lookup_slow+0x20f/0x3f0 fs/namei.c:1696 walk_component+0x680/0x21a0 fs/namei.c:1825 lookup_last fs/namei.c:2293 [inline] path_lookupat.isra.40+0x17f/0x810 fs/namei.c:2343 filename_lookup.part.53+0x15b/0x340 fs/namei.c:2377 filename_lookup fs/namei.c:2370 [inline] user_path_at_empty+0x39/0x40 fs/namei.c:2631 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0xb6/0x130 fs/stat.c:185 vfs_stat include/linux/fs.h:3061 [inline] SYSC_newstat+0x7d/0xc0 fs/stat.c:337 SyS_newstat+0x9/0x10 fs/stat.c:333 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x459519 RSP: 002b:00007fe8a435cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000459519 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000580 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe8a435d6d4 R13: 00000000004e585b R14: 00000000004deb88 R15: 00000000ffffffff INFO: task syz-executor.1:7016 blocked for more than 140 seconds. Not tainted 4.14.177-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D29048 7016 6103 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x780/0x1d20 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:588 [inline] rwsem_down_write_failed+0x54f/0xb50 kernel/locking/rwsem-xadd.c:617 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105 __down_write arch/x86/include/asm/rwsem.h:126 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:56 inode_lock include/linux/fs.h:719 [inline] fuse_reverse_inval_entry+0x92/0x5c0 fs/fuse/dir.c:972 fuse_notify_delete fs/fuse/dev.c:1562 [inline] fuse_notify fs/fuse/dev.c:1796 [inline] fuse_dev_do_write+0xe58/0x2310 fs/fuse/dev.c:1871 fuse_dev_write+0x11a/0x180 fs/fuse/dev.c:1955 call_write_iter include/linux/fs.h:1778 [inline] new_sync_write fs/read_write.c:469 [inline] __vfs_write+0x413/0x840 fs/read_write.c:482 vfs_write+0x150/0x4f0 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0x100/0x250 fs/read_write.c:582 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x459519 RSP: 002b:00007fe8a433bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459519 RDX: 000000000000002e RSI: 0000000020000000 RDI: 0000000000000003 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe8a433c6d4 R13: 00000000004c8d0e R14: 00000000004dfc50 R15: 00000000ffffffff INFO: task syz-executor.1:7023 blocked for more than 140 seconds. Not tainted 4.14.177-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D29176 7023 6103 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x780/0x1d20 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:588 [inline] rwsem_down_write_failed+0x54f/0xb50 kernel/locking/rwsem-xadd.c:617 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105 __down_write arch/x86/include/asm/rwsem.h:126 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:56 inode_lock include/linux/fs.h:719 [inline] lock_mount+0x82/0x290 fs/namespace.c:2119 do_add_mount+0x22/0x310 fs/namespace.c:2496 do_new_mount fs/namespace.c:2563 [inline] do_mount+0x12cf/0x26a0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xb8/0xd0 fs/namespace.c:3072 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x459519 RSP: 002b:00007fe8a431ac78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000459519 RDX: 0000000020000000 RSI: 0000000020000180 RDI: 0000000000000000 RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 00007fe8a431b6d4 R13: 00000000004c595e R14: 00000000004d9fe0 R15: 00000000ffffffff INFO: task syz-executor.1:7049 blocked for more than 140 seconds. Not tainted 4.14.177-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D27664 7049 6103 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x780/0x1d20 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:588 [inline] rwsem_down_write_failed+0x54f/0xb50 kernel/locking/rwsem-xadd.c:617 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105 __down_write arch/x86/include/asm/rwsem.h:126 [inline] down_write+0x53/0x90 kernel/locking/rwsem.c:56 inode_lock include/linux/fs.h:719 [inline] lock_mount+0x82/0x290 fs/namespace.c:2119 do_add_mount+0x22/0x310 fs/namespace.c:2496 do_new_mount fs/namespace.c:2563 [inline] do_mount+0x12cf/0x26a0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xb8/0xd0 fs/namespace.c:3072 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x459519 RSP: 002b:00007fe8a42f9c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000459519 RDX: 0000000020000240 RSI: 0000000020000200 RDI: 0000000000000000 RBP: 000000000075c118 R08: 0000000020000400 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe8a42fa6d4 R13: 00000000004c5932 R14: 00000000004da0a0 R15: 00000000ffffffff INFO: task syz-executor.1:7050 blocked for more than 140 seconds. Not tainted 4.14.177-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28920 7050 6103 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x780/0x1d20 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline] rwsem_down_read_failed+0x1fc/0x390 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:66 [inline] down_read+0x49/0xb0 kernel/locking/rwsem.c:26 inode_lock_shared include/linux/fs.h:729 [inline] lookup_slow+0x123/0x3f0 fs/namei.c:1674 walk_component+0x680/0x21a0 fs/namei.c:1825 lookup_last fs/namei.c:2293 [inline] path_lookupat.isra.40+0x17f/0x810 fs/namei.c:2343 filename_lookup.part.53+0x15b/0x340 fs/namei.c:2377 filename_lookup fs/namei.c:2370 [inline] user_path_at_empty+0x39/0x40 fs/namei.c:2631 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0xb6/0x130 fs/stat.c:185 vfs_stat include/linux/fs.h:3061 [inline] SYSC_newstat+0x7d/0xc0 fs/stat.c:337 SyS_newstat+0x9/0x10 fs/stat.c:333 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x459519 RSP: 002b:00007fe8a42d8c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000459519 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000580 RBP: 000000000075c1c0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe8a42d96d4 R13: 00000000004e585b R14: 00000000004deb88 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1012: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4548 1 lock held by in:imklog/5605: #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0x8e/0xc0 fs/file.c:769 2 locks held by syz-executor.5/6973: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock_shared include/linux/fs.h:729 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lookup_slow+0x123/0x3f0 fs/namei.c:1674 #1: (&fi->mutex){+.+.}, at: [] fuse_lock_inode+0x9f/0xd0 fs/fuse/inode.c:365 1 lock held by syz-executor.5/6977: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lock_mount+0x82/0x290 fs/namespace.c:2119 2 locks held by syz-executor.5/6978: #0: (&fc->killsb){.+.+}, at: [] fuse_notify_delete fs/fuse/dev.c:1559 [inline] #0: (&fc->killsb){.+.+}, at: [] fuse_notify fs/fuse/dev.c:1796 [inline] #0: (&fc->killsb){.+.+}, at: [] fuse_dev_do_write+0x1988/0x2310 fs/fuse/dev.c:1871 #1: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #1: (&type->i_mutex_dir_key#8){++++}, at: [] fuse_reverse_inval_entry+0x92/0x5c0 fs/fuse/dir.c:972 1 lock held by syz-executor.5/6991: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lock_mount+0x82/0x290 fs/namespace.c:2119 1 lock held by syz-executor.5/6992: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock_shared include/linux/fs.h:729 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lookup_slow+0x123/0x3f0 fs/namei.c:1674 2 locks held by syz-executor.1/7010: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock_shared include/linux/fs.h:729 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lookup_slow+0x123/0x3f0 fs/namei.c:1674 #1: (&fi->mutex){+.+.}, at: [] fuse_lock_inode+0x9f/0xd0 fs/fuse/inode.c:365 2 locks held by syz-executor.1/7016: #0: (&fc->killsb){.+.+}, at: [] fuse_notify_delete fs/fuse/dev.c:1559 [inline] #0: (&fc->killsb){.+.+}, at: [] fuse_notify fs/fuse/dev.c:1796 [inline] #0: (&fc->killsb){.+.+}, at: [] fuse_dev_do_write+0x1988/0x2310 fs/fuse/dev.c:1871 #1: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #1: (&type->i_mutex_dir_key#8){++++}, at: [] fuse_reverse_inval_entry+0x92/0x5c0 fs/fuse/dir.c:972 1 lock held by syz-executor.1/7023: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lock_mount+0x82/0x290 fs/namespace.c:2119 1 lock held by syz-executor.1/7049: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lock_mount+0x82/0x290 fs/namespace.c:2119 1 lock held by syz-executor.1/7050: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock_shared include/linux/fs.h:729 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lookup_slow+0x123/0x3f0 fs/namei.c:1674 2 locks held by syz-executor.3/7019: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock_shared include/linux/fs.h:729 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lookup_slow+0x123/0x3f0 fs/namei.c:1674 #1: (&fi->mutex){+.+.}, at: [] fuse_lock_inode+0x9f/0xd0 fs/fuse/inode.c:365 1 lock held by syz-executor.3/7027: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lock_mount+0x82/0x290 fs/namespace.c:2119 2 locks held by syz-executor.3/7030: #0: (&fc->killsb){.+.+}, at: [] fuse_notify_delete fs/fuse/dev.c:1559 [inline] #0: (&fc->killsb){.+.+}, at: [] fuse_notify fs/fuse/dev.c:1796 [inline] #0: (&fc->killsb){.+.+}, at: [] fuse_dev_do_write+0x1988/0x2310 fs/fuse/dev.c:1871 #1: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #1: (&type->i_mutex_dir_key#8){++++}, at: [] fuse_reverse_inval_entry+0x92/0x5c0 fs/fuse/dir.c:972 1 lock held by syz-executor.3/7057: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lock_mount+0x82/0x290 fs/namespace.c:2119 1 lock held by syz-executor.3/7058: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock_shared include/linux/fs.h:729 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lookup_slow+0x123/0x3f0 fs/namei.c:1674 2 locks held by syz-executor.2/7034: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock_shared include/linux/fs.h:729 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lookup_slow+0x123/0x3f0 fs/namei.c:1674 #1: (&fi->mutex){+.+.}, at: [] fuse_lock_inode+0x9f/0xd0 fs/fuse/inode.c:365 1 lock held by syz-executor.2/7039: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lock_mount+0x82/0x290 fs/namespace.c:2119 2 locks held by syz-executor.2/7040: #0: (&fc->killsb){.+.+}, at: [] fuse_notify_delete fs/fuse/dev.c:1559 [inline] #0: (&fc->killsb){.+.+}, at: [] fuse_notify fs/fuse/dev.c:1796 [inline] #0: (&fc->killsb){.+.+}, at: [] fuse_dev_do_write+0x1988/0x2310 fs/fuse/dev.c:1871 #1: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #1: (&type->i_mutex_dir_key#8){++++}, at: [] fuse_reverse_inval_entry+0x92/0x5c0 fs/fuse/dir.c:972 1 lock held by syz-executor.2/7065: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lock_mount+0x82/0x290 fs/namespace.c:2119 2 locks held by syz-executor.4/7074: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock_shared include/linux/fs.h:729 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lookup_slow+0x123/0x3f0 fs/namei.c:1674 #1: (&fi->mutex){+.+.}, at: [] fuse_lock_inode+0x9f/0xd0 fs/fuse/inode.c:365 1 lock held by syz-executor.4/7083: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lock_mount+0x82/0x290 fs/namespace.c:2119 2 locks held by syz-executor.4/7087: #0: (&fc->killsb){.+.+}, at: [] fuse_notify_delete fs/fuse/dev.c:1559 [inline] #0: (&fc->killsb){.+.+}, at: [] fuse_notify fs/fuse/dev.c:1796 [inline] #0: (&fc->killsb){.+.+}, at: [] fuse_dev_do_write+0x1988/0x2310 fs/fuse/dev.c:1871 #1: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #1: (&type->i_mutex_dir_key#8){++++}, at: [] fuse_reverse_inval_entry+0x92/0x5c0 fs/fuse/dir.c:972 1 lock held by syz-executor.4/7089: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lock_mount+0x82/0x290 fs/namespace.c:2119 2 locks held by syz-executor.0/7080: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock_shared include/linux/fs.h:729 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lookup_slow+0x123/0x3f0 fs/namei.c:1674 #1: (&fi->mutex){+.+.}, at: [] fuse_lock_inode+0x9f/0xd0 fs/fuse/inode.c:365 2 locks held by syz-executor.0/7086: #0: (&fc->killsb){.+.+}, at: [] fuse_notify_delete fs/fuse/dev.c:1559 [inline] #0: (&fc->killsb){.+.+}, at: [] fuse_notify fs/fuse/dev.c:1796 [inline] #0: (&fc->killsb){.+.+}, at: [] fuse_dev_do_write+0x1988/0x2310 fs/fuse/dev.c:1871 #1: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #1: (&type->i_mutex_dir_key#8){++++}, at: [] fuse_reverse_inval_entry+0x92/0x5c0 fs/fuse/dir.c:972 1 lock held by syz-executor.0/7088: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lock_mount+0x82/0x290 fs/namespace.c:2119 1 lock held by syz-executor.0/7095: #0: (&type->i_mutex_dir_key#8){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #0: (&type->i_mutex_dir_key#8){++++}, at: [] lock_mount+0x82/0x290 fs/namespace.c:2119 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1012 Comm: khungtaskd Not tainted 4.14.177-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xf7/0x13b lib/dump_stack.c:58 nmi_cpu_backtrace.cold.4+0x3e/0x76 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0xe5/0x119 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:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x522/0xb40 kernel/hung_task.c:274 kthread+0x338/0x400 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3423 Comm: systemd-journal Not tainted 4.14.177-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff888095b3a200 task.stack: ffff888095b40000 RIP: 0010:__read_once_size include/linux/compiler.h:183 [inline] RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:2361 [inline] RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:2381 [inline] RIP: 0010:validate_chain kernel/locking/lockdep.c:2435 [inline] RIP: 0010:__lock_acquire+0xd7f/0x4500 kernel/locking/lockdep.c:3491 RSP: 0018:ffff888095b47860 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: 000000005df7a95e RCX: ffff888095b3aa88 RDX: 1ffffffff11cef92 RSI: ffff888095b3aab0 RDI: ffff888095b3aad1 RBP: ffff888095b47a28 R08: ffff888095b3aad0 R09: 00000000000044ea R10: 0000000000000000 R11: ffff888095b3a200 R12: 00000000caa0bb9b R13: 00000000ead2a131 R14: 68318584b5735ccc R15: ffff888095b3aab0 FS: 00007fad58da38c0(0000) GS:ffff8880aee00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fad56193000 CR3: 0000000095932000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x173/0x400 kernel/locking/lockdep.c:3998 seqcount_lockdep_reader_access include/linux/seqlock.h:81 [inline] read_seqcount_begin include/linux/seqlock.h:164 [inline] set_root+0x107/0x4d0 fs/namei.c:835 path_init+0x864/0x17d0 fs/namei.c:2220 path_parentat.isra.37+0x16/0x130 fs/namei.c:2394 filename_parentat.isra.51.part.52+0x148/0x3e0 fs/namei.c:2420 filename_parentat fs/namei.c:3655 [inline] filename_create+0xae/0x410 fs/namei.c:3657 user_path_create fs/namei.c:3732 [inline] SYSC_mkdirat fs/namei.c:3864 [inline] SyS_mkdirat fs/namei.c:3856 [inline] SYSC_mkdir fs/namei.c:3883 [inline] SyS_mkdir+0x9b/0x230 fs/namei.c:3881 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x7fad5805f687 RSP: 002b:00007ffdf488b878 EFLAGS: 00000293 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007ffdf488e8e0 RCX: 00007fad5805f687 RDX: 0000000000000000 RSI: 00000000000001ed RDI: 0000556d09fd28c0 RBP: 00007ffdf488b8b0 R08: 0000556d08fbb3e5 R09: 0000000000000018 R10: 0000000000000069 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000001 R14: 0000556d09fd28c0 R15: 00007ffdf488bef0 Code: af c6 48 c1 e8 31 49 89 c1 48 8d 04 c5 40 55 e5 88 48 89 c2 48 89 44 24 60 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 <0f> 85 47 2a 00 00 4a 8b 1c cd 40 55 e5 88 48 85 db 0f 84 ca 00