bisecting fixing commit since 6500aa436df40a46998f7a56a32e8199a3513e6d building syzkaller on 442206d76b974cca2d83ec763d4cf5ee829eb7d6 testing commit 6500aa436df40a46998f7a56a32e8199a3513e6d with gcc (GCC) 8.1.0 kernel signature: d2ba598ac3b74153f76459e9a4281f93e5e87cc841d715c4cb8c09d14ec85068 all runs: crashed: INFO: task hung in __fuse_request_send testing current HEAD 5692097116094a4a7045abcc1dbc172dbdc5657e testing commit 5692097116094a4a7045abcc1dbc172dbdc5657e with gcc (GCC) 8.1.0 kernel signature: 4a8f6bf680d848d4e2542df6e50c6712d32c28427d66e89cf421e8a9ca99b29a all runs: crashed: INFO: task hung in __fuse_request_send revisions tested: 2, total time: 32m40.582628078s (build: 18m36.212035904s, test: 12m44.159540327s) the crash still happens on HEAD commit msg: Linux 4.19.109 crash: INFO: task hung in __fuse_request_send IPv6: ADDRCONF(NETDEV_UP): hsr0: link is not ready IPv6: ADDRCONF(NETDEV_CHANGE): hsr0: link becomes ready IPv6: ADDRCONF(NETDEV_UP): vxcan1: link is not ready 8021q: adding VLAN 0 to HW filter on device batadv0 INFO: task syz-executor.5:7120 blocked for more than 140 seconds. Not tainted 4.19.109-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D27336 7120 7104 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 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+0x694/0x2320 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:3128 [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: 0033:0x4592c9 Code: 24 48 c7 44 24 10 09 00 00 00 e8 82 ad ff ff 0f b6 44 24 18 88 44 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 8a 8f ff ff eb a8 cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 76 68 RSP: 002b:00007fa6bcd3fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00000000004592c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000580 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa6bcd406d4 R13: 00000000004e52fb R14: 00000000004de648 R15: 00000000ffffffff INFO: task syz-executor.5:7121 blocked for more than 140 seconds. Not tainted 4.19.109-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28616 7121 7104 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x5c6/0xbf0 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:747 [inline] fuse_reverse_inval_entry+0x9a/0x5d0 fs/fuse/dir.c:987 fuse_notify_delete fs/fuse/dev.c:1568 [inline] fuse_notify fs/fuse/dev.c:1802 [inline] fuse_dev_do_write+0xb7d/0x2350 fs/fuse/dev.c:1877 fuse_dev_write+0x12a/0x1b0 fs/fuse/dev.c:1961 call_write_iter include/linux/fs.h:1820 [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: 0033:0x4592c9 Code: 24 48 c7 44 24 10 09 00 00 00 e8 82 ad ff ff 0f b6 44 24 18 88 44 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 8a 8f ff ff eb a8 cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 76 68 RSP: 002b:00007fa6bcd1ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004592c9 RDX: 000000000000002e RSI: 0000000020000000 RDI: 0000000000000003 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa6bcd1f6d4 R13: 00000000004c8aa3 R14: 00000000004df6e0 R15: 00000000ffffffff INFO: task syz-executor.5:7122 blocked for more than 140 seconds. Not tainted 4.19.109-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28824 7122 7104 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x5c6/0xbf0 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:747 [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+0xba/0xe0 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: 0033:0x4592c9 Code: 24 48 c7 44 24 10 09 00 00 00 e8 82 ad ff ff 0f b6 44 24 18 88 44 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 8a 8f ff ff eb a8 cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 76 68 RSP: 002b:00007fa6bccfdc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00000000004592c9 RDX: 0000000020000000 RSI: 0000000020000180 RDI: 0000000000000000 RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 00007fa6bccfe6d4 R13: 00000000004c570b R14: 00000000004d9aa0 R15: 00000000ffffffff INFO: task syz-executor.5:7148 blocked for more than 140 seconds. Not tainted 4.19.109-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D27960 7148 7104 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x5c6/0xbf0 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:747 [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+0xba/0xe0 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: 0033:0x4592c9 Code: 24 48 c7 44 24 10 09 00 00 00 e8 82 ad ff ff 0f b6 44 24 18 88 44 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 8a 8f ff ff eb a8 cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 76 68 RSP: 002b:00007fa6bccdcc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00000000004592c9 RDX: 0000000020000240 RSI: 0000000020000200 RDI: 0000000000000000 RBP: 000000000075c118 R08: 0000000020000400 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa6bccdd6d4 R13: 00000000004c56df R14: 00000000004d9b60 R15: 00000000ffffffff INFO: task syz-executor.5:7149 blocked for more than 140 seconds. Not tainted 4.19.109-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D29144 7149 7104 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 __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:757 [inline] lookup_slow+0x43/0x70 fs/namei.c:1688 walk_component+0x694/0x2320 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:3128 [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: 0033:0x4592c9 Code: 24 48 c7 44 24 10 09 00 00 00 e8 82 ad ff ff 0f b6 44 24 18 88 44 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 8a 8f ff ff eb a8 cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 76 68 RSP: 002b:00007fa6bccbbc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00000000004592c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000580 RBP: 000000000075c1c0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa6bccbc6d4 R13: 00000000004e52fb R14: 00000000004de648 R15: 00000000ffffffff INFO: task syz-executor.3:7124 blocked for more than 140 seconds. Not tainted 4.19.109-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D27272 7124 7100 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 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+0x694/0x2320 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:3128 [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: 0033:0x4592c9 Code: 24 48 c7 44 24 10 09 00 00 00 e8 82 ad ff ff 0f b6 44 24 18 88 44 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 8a 8f ff ff eb a8 cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 76 68 RSP: 002b:00007f2cdb89cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00000000004592c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000580 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2cdb89d6d4 R13: 00000000004e52fb R14: 00000000004de648 R15: 00000000ffffffff INFO: task syz-executor.3:7126 blocked for more than 140 seconds. Not tainted 4.19.109-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D29608 7126 7100 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x5c6/0xbf0 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:747 [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+0xba/0xe0 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: 0033:0x4592c9 Code: 24 48 c7 44 24 10 09 00 00 00 e8 82 ad ff ff 0f b6 44 24 18 88 44 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 8a 8f ff ff eb a8 cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 76 68 RSP: 002b:00007f2cdb87bc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00000000004592c9 RDX: 0000000020000000 RSI: 0000000020000180 RDI: 0000000000000000 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 00007f2cdb87c6d4 R13: 00000000004c570b R14: 00000000004d9aa0 R15: 00000000ffffffff INFO: task syz-executor.3:7128 blocked for more than 140 seconds. Not tainted 4.19.109-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28920 7128 7100 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x5c6/0xbf0 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:747 [inline] fuse_reverse_inval_entry+0x9a/0x5d0 fs/fuse/dir.c:987 fuse_notify_delete fs/fuse/dev.c:1568 [inline] fuse_notify fs/fuse/dev.c:1802 [inline] fuse_dev_do_write+0xb7d/0x2350 fs/fuse/dev.c:1877 fuse_dev_write+0x12a/0x1b0 fs/fuse/dev.c:1961 call_write_iter include/linux/fs.h:1820 [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: 0033:0x4592c9 Code: 24 48 c7 44 24 10 09 00 00 00 e8 82 ad ff ff 0f b6 44 24 18 88 44 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 8a 8f ff ff eb a8 cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 76 68 RSP: 002b:00007f2cdb85ac78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004592c9 RDX: 000000000000002e RSI: 0000000020000000 RDI: 0000000000000003 RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2cdb85b6d4 R13: 00000000004c8aa3 R14: 00000000004df6e0 R15: 00000000ffffffff INFO: task syz-executor.3:7153 blocked for more than 140 seconds. Not tainted 4.19.109-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D27880 7153 7100 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline] rwsem_down_write_failed+0x5c6/0xbf0 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:747 [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+0xba/0xe0 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: 0033:0x4592c9 Code: 24 48 c7 44 24 10 09 00 00 00 e8 82 ad ff ff 0f b6 44 24 18 88 44 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 8a 8f ff ff eb a8 cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 76 68 RSP: 002b:00007f2cdb839c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00000000004592c9 RDX: 0000000020000240 RSI: 0000000020000200 RDI: 0000000000000000 RBP: 000000000075c118 R08: 0000000020000400 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2cdb83a6d4 R13: 00000000004c56df R14: 00000000004d9b60 R15: 00000000ffffffff INFO: task syz-executor.3:7154 blocked for more than 140 seconds. Not tainted 4.19.109-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D29144 7154 7100 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x78c/0x1c10 kernel/sched/core.c:3515 schedule+0x7f/0x1b0 kernel/sched/core.c:3559 __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:757 [inline] lookup_slow+0x43/0x70 fs/namei.c:1688 walk_component+0x694/0x2320 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:3128 [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: 0033:0x4592c9 Code: 24 48 c7 44 24 10 09 00 00 00 e8 82 ad ff ff 0f b6 44 24 18 88 44 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 8a 8f ff ff eb a8 cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 76 68 RSP: 002b:00007f2cdb818c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00000000004592c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000580 RBP: 000000000075c1c0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2cdb8196d4 R13: 00000000004e52fb R14: 00000000004de648 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/1036: #0: 000000005321fbef (rcu_read_lock){....}, at: debug_show_all_locks+0x5b/0x27a kernel/locking/lockdep.c:4438 1 lock held by rsyslogd/6855: #0: 00000000051a577b (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xa7/0xd0 fs/file.c:767 2 locks held by getty/6977: #0: 00000000e3f32bb1 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000d0bb06a4 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1910 drivers/tty/n_tty.c:2154 2 locks held by getty/6978: #0: 0000000030dca649 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000735a4304 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1910 drivers/tty/n_tty.c:2154 2 locks held by getty/6979: #0: 00000000e539df20 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 00000000e74001f8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1910 drivers/tty/n_tty.c:2154 2 locks held by getty/6980: #0: 000000006d6f1f29 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000009a73b4bb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1910 drivers/tty/n_tty.c:2154 2 locks held by getty/6981: #0: 0000000076746488 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 0000000028051ad9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1910 drivers/tty/n_tty.c:2154 2 locks held by getty/6982: #0: 00000000ede59928 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000009b484acf (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1910 drivers/tty/n_tty.c:2154 2 locks held by getty/6983: #0: 00000000536eb005 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000005af6d9a9 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x1ee/0x1910 drivers/tty/n_tty.c:2154 2 locks held by syz-executor.5/7120: #0: 00000000a79c5211 (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:757 [inline] #0: 00000000a79c5211 (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 #1: 0000000074943b36 (&fi->mutex){+.+.}, at: fuse_lock_inode+0x9a/0xc0 fs/fuse/inode.c:365 2 locks held by syz-executor.5/7121: #0: 00000000c4323fd7 (&fc->killsb){.+.+}, at: fuse_notify_delete fs/fuse/dev.c:1565 [inline] #0: 00000000c4323fd7 (&fc->killsb){.+.+}, at: fuse_notify fs/fuse/dev.c:1802 [inline] #0: 00000000c4323fd7 (&fc->killsb){.+.+}, at: fuse_dev_do_write+0x19c5/0x2350 fs/fuse/dev.c:1877 #1: 00000000a79c5211 (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:747 [inline] #1: 00000000a79c5211 (&type->i_mutex_dir_key#8){++++}, at: fuse_reverse_inval_entry+0x9a/0x5d0 fs/fuse/dir.c:987 1 lock held by syz-executor.5/7122: #0: 00000000a79c5211 (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:747 [inline] #0: 00000000a79c5211 (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 1 lock held by syz-executor.5/7148: #0: 00000000a79c5211 (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:747 [inline] #0: 00000000a79c5211 (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 1 lock held by syz-executor.5/7149: #0: 00000000a79c5211 (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:757 [inline] #0: 00000000a79c5211 (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 2 locks held by syz-executor.3/7124: #0: 000000006f5bf0ba (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:757 [inline] #0: 000000006f5bf0ba (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 #1: 000000007bc5602d (&fi->mutex){+.+.}, at: fuse_lock_inode+0x9a/0xc0 fs/fuse/inode.c:365 1 lock held by syz-executor.3/7126: #0: 000000006f5bf0ba (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:747 [inline] #0: 000000006f5bf0ba (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 2 locks held by syz-executor.3/7128: #0: 00000000c3fea2e1 (&fc->killsb){.+.+}, at: fuse_notify_delete fs/fuse/dev.c:1565 [inline] #0: 00000000c3fea2e1 (&fc->killsb){.+.+}, at: fuse_notify fs/fuse/dev.c:1802 [inline] #0: 00000000c3fea2e1 (&fc->killsb){.+.+}, at: fuse_dev_do_write+0x19c5/0x2350 fs/fuse/dev.c:1877 #1: 000000006f5bf0ba (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:747 [inline] #1: 000000006f5bf0ba (&type->i_mutex_dir_key#8){++++}, at: fuse_reverse_inval_entry+0x9a/0x5d0 fs/fuse/dir.c:987 1 lock held by syz-executor.3/7153: #0: 000000006f5bf0ba (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:747 [inline] #0: 000000006f5bf0ba (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 1 lock held by syz-executor.3/7154: #0: 000000006f5bf0ba (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:757 [inline] #0: 000000006f5bf0ba (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 2 locks held by syz-executor.1/7130: #0: 0000000089efdaa9 (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:757 [inline] #0: 0000000089efdaa9 (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 #1: 00000000667c1165 (&fi->mutex){+.+.}, at: fuse_lock_inode+0x9a/0xc0 fs/fuse/inode.c:365 1 lock held by syz-executor.1/7131: #0: 0000000089efdaa9 (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:747 [inline] #0: 0000000089efdaa9 (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 2 locks held by syz-executor.1/7132: #0: 00000000327e7763 (&fc->killsb){.+.+}, at: fuse_notify_delete fs/fuse/dev.c:1565 [inline] #0: 00000000327e7763 (&fc->killsb){.+.+}, at: fuse_notify fs/fuse/dev.c:1802 [inline] #0: 00000000327e7763 (&fc->killsb){.+.+}, at: fuse_dev_do_write+0x19c5/0x2350 fs/fuse/dev.c:1877 #1: 0000000089efdaa9 (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:747 [inline] #1: 0000000089efdaa9 (&type->i_mutex_dir_key#8){++++}, at: fuse_reverse_inval_entry+0x9a/0x5d0 fs/fuse/dir.c:987 1 lock held by syz-executor.1/7157: #0: 0000000089efdaa9 (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:747 [inline] #0: 0000000089efdaa9 (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 1 lock held by syz-executor.1/7158: #0: 0000000089efdaa9 (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:757 [inline] #0: 0000000089efdaa9 (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 2 locks held by syz-executor.2/7135: #0: 00000000b1c777fa (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:757 [inline] #0: 00000000b1c777fa (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 #1: 0000000039c8fdc6 (&fi->mutex){+.+.}, at: fuse_lock_inode+0x9a/0xc0 fs/fuse/inode.c:365 1 lock held by syz-executor.2/7136: #0: 00000000b1c777fa (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:747 [inline] #0: 00000000b1c777fa (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 2 locks held by syz-executor.2/7137: #0: 00000000479a6f9d (&fc->killsb){.+.+}, at: fuse_notify_delete fs/fuse/dev.c:1565 [inline] #0: 00000000479a6f9d (&fc->killsb){.+.+}, at: fuse_notify fs/fuse/dev.c:1802 [inline] #0: 00000000479a6f9d (&fc->killsb){.+.+}, at: fuse_dev_do_write+0x19c5/0x2350 fs/fuse/dev.c:1877 #1: 00000000b1c777fa (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:747 [inline] #1: 00000000b1c777fa (&type->i_mutex_dir_key#8){++++}, at: fuse_reverse_inval_entry+0x9a/0x5d0 fs/fuse/dir.c:987 1 lock held by syz-executor.2/7162: #0: 00000000b1c777fa (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:747 [inline] #0: 00000000b1c777fa (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 2 locks held by syz-executor.4/7140: #0: 00000000b3ffea66 (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:757 [inline] #0: 00000000b3ffea66 (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 #1: 00000000c9c33d03 (&fi->mutex){+.+.}, at: fuse_lock_inode+0x9a/0xc0 fs/fuse/inode.c:365 1 lock held by syz-executor.4/7144: #0: 00000000b3ffea66 (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:747 [inline] #0: 00000000b3ffea66 (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 2 locks held by syz-executor.4/7146: #0: 00000000f3f6fe88 (&fc->killsb){.+.+}, at: fuse_notify_delete fs/fuse/dev.c:1565 [inline] #0: 00000000f3f6fe88 (&fc->killsb){.+.+}, at: fuse_notify fs/fuse/dev.c:1802 [inline] #0: 00000000f3f6fe88 (&fc->killsb){.+.+}, at: fuse_dev_do_write+0x19c5/0x2350 fs/fuse/dev.c:1877 #1: 00000000b3ffea66 (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:747 [inline] #1: 00000000b3ffea66 (&type->i_mutex_dir_key#8){++++}, at: fuse_reverse_inval_entry+0x9a/0x5d0 fs/fuse/dir.c:987 1 lock held by syz-executor.4/7166: #0: 00000000b3ffea66 (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:747 [inline] #0: 00000000b3ffea66 (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 1 lock held by syz-executor.4/7167: #0: 00000000b3ffea66 (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:757 [inline] #0: 00000000b3ffea66 (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 2 locks held by syz-executor.0/7143: #0: 000000006cac915e (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:757 [inline] #0: 000000006cac915e (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 #1: 0000000046a5668e (&fi->mutex){+.+.}, at: fuse_lock_inode+0x9a/0xc0 fs/fuse/inode.c:365 1 lock held by syz-executor.0/7145: #0: 000000006cac915e (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:747 [inline] #0: 000000006cac915e (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 2 locks held by syz-executor.0/7147: #0: 00000000d2593a9d (&fc->killsb){.+.+}, at: fuse_notify_delete fs/fuse/dev.c:1565 [inline] #0: 00000000d2593a9d (&fc->killsb){.+.+}, at: fuse_notify fs/fuse/dev.c:1802 [inline] #0: 00000000d2593a9d (&fc->killsb){.+.+}, at: fuse_dev_do_write+0x19c5/0x2350 fs/fuse/dev.c:1877 #1: 000000006cac915e (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:747 [inline] #1: 000000006cac915e (&type->i_mutex_dir_key#8){++++}, at: fuse_reverse_inval_entry+0x9a/0x5d0 fs/fuse/dir.c:987 1 lock held by syz-executor.0/7171: #0: 000000006cac915e (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:747 [inline] #0: 000000006cac915e (&type->i_mutex_dir_key#8){++++}, at: lock_mount+0x82/0x290 fs/namespace.c:2039 1 lock held by syz-executor.0/7172: #0: 000000006cac915e (&type->i_mutex_dir_key#8){++++}, at: inode_lock_shared include/linux/fs.h:757 [inline] #0: 000000006cac915e (&type->i_mutex_dir_key#8){++++}, at: lookup_slow+0x43/0x70 fs/namei.c:1688 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1036 Comm: khungtaskd Not tainted 4.19.109-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+0x123/0x177 lib/dump_stack.c:118 nmi_cpu_backtrace.cold.4+0x3e/0x76 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0xe6/0x11a 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+0x324/0x3e0 kernel/kthread.c:246 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 CPU: 0 PID: 23 Comm: kworker/u4:1 Not tainted 4.19.109-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:separate_irq_context kernel/locking/lockdep.c:3054 [inline] RIP: 0010:__lock_acquire+0xd3a/0x4980 kernel/locking/lockdep.c:3402 Code: 83 e2 07 38 d0 7f 08 84 c0 0f 85 c7 2b 00 00 45 32 7a 21 41 83 e7 60 0f 85 fc 03 00 00 4c 89 ea 44 89 e8 48 c1 ea 20 41 01 d5 <29> d3 c1 c2 04 31 d3 41 89 dc 42 8d 1c 2b e9 48 fb ff ff 85 d2 0f RSP: 0018:ffff8880a98dfa90 EFLAGS: 00000006 RAX: 00000000575f3026 RBX: 000000000000002b RCX: 1ffff110153199de RDX: 000000000ac62bb8 RSI: ffff8880a98cce80 RDI: ffff8880a98ccef1 RBP: ffff8880a98dfc80 R08: ffff8880a98ccef0 R09: 0000000000000002 R10: ffff8880a98cced0 R11: 0000000000000000 R12: 000000000000002b R13: 0000000062255bde R14: ffff8880a98cc600 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000001cfc000 CR3: 0000000082c5b000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x173/0x3d0 kernel/locking/lockdep.c:3903 rcu_lock_acquire include/linux/rcupdate.h:242 [inline] rcu_read_lock include/linux/rcupdate.h:627 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:419 [inline] batadv_nc_worker+0xec/0x630 net/batman-adv/network-coding.c:730 process_one_work+0x830/0x1670 kernel/workqueue.c:2153 worker_thread+0x85/0xb60 kernel/workqueue.c:2296 kthread+0x324/0x3e0 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415