====================================================== binder: 27848:27852 ERROR: BC_REGISTER_LOOPER called without request WARNING: possible circular locking dependency detected 5.0.0-rc2+ #33 Not tainted ------------------------------------------------------ syz-executor1/27853 is trying to acquire lock: 000000003c2ada32 (&sig->cred_guard_mutex){+.+.}, at: do_io_accounting+0x1d1/0xfe0 fs/proc/base.c:2711 but task is already holding lock: 0000000027fef0d6 (&p->lock){+.+.}, at: seq_read+0x71/0x1130 fs/seq_file.c:161 which lock already depends on the new lock. binder: 27848:27856 got reply transaction with no transaction stack the existing dependency chain (in reverse order) is: -> #2 (&p->lock){+.+.}: __mutex_lock_common kernel/locking/mutex.c:925 [inline] __mutex_lock+0x12f/0x1670 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 seq_read+0x71/0x1130 fs/seq_file.c:161 proc_reg_read+0x29a/0x3c0 fs/proc/inode.c:229 do_loop_readv_writev fs/read_write.c:700 [inline] do_loop_readv_writev fs/read_write.c:687 [inline] do_iter_read+0x4a9/0x660 fs/read_write.c:921 vfs_readv+0x175/0x1c0 fs/read_write.c:983 kernel_readv fs/splice.c:362 [inline] default_file_splice_read+0x50c/0xac0 fs/splice.c:417 do_splice_to+0x12a/0x190 fs/splice.c:880 do_splice+0xff7/0x1410 fs/splice.c:1178 __do_sys_splice fs/splice.c:1419 [inline] __se_sys_splice fs/splice.c:1399 [inline] __x64_sys_splice+0x2c6/0x330 fs/splice.c:1399 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #1 (&pipe->mutex/1){+.+.}: __mutex_lock_common kernel/locking/mutex.c:925 [inline] __mutex_lock+0x12f/0x1670 kernel/locking/mutex.c:1072 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087 __pipe_lock fs/pipe.c:83 [inline] fifo_open+0x159/0xb00 fs/pipe.c:905 do_dentry_open+0x48a/0x1210 fs/open.c:771 vfs_open+0xa0/0xd0 fs/open.c:880 do_last fs/namei.c:3418 [inline] path_openat+0x144f/0x5650 fs/namei.c:3534 do_filp_open+0x26f/0x370 fs/namei.c:3564 do_open_execat+0x20e/0x930 fs/exec.c:856 __do_execve_file.isra.0+0x1966/0x2700 fs/exec.c:1758 do_execveat_common fs/exec.c:1865 [inline] do_execve fs/exec.c:1882 [inline] __do_sys_execve fs/exec.c:1963 [inline] __se_sys_execve fs/exec.c:1958 [inline] __x64_sys_execve+0x8f/0xc0 fs/exec.c:1958 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (&sig->cred_guard_mutex){+.+.}: lock_acquire+0x1db/0x570 kernel/locking/lockdep.c:3841 __mutex_lock_common kernel/locking/mutex.c:925 [inline] __mutex_lock+0x12f/0x1670 kernel/locking/mutex.c:1072 mutex_lock_killable_nested+0x16/0x20 kernel/locking/mutex.c:1102 do_io_accounting+0x1d1/0xfe0 fs/proc/base.c:2711 proc_tgid_io_accounting+0x23/0x30 fs/proc/base.c:2760 proc_single_show+0xf6/0x180 fs/proc/base.c:739 seq_read+0x4db/0x1130 fs/seq_file.c:229 __vfs_read+0x116/0xb20 fs/read_write.c:416 vfs_read+0x194/0x3e0 fs/read_write.c:452 ksys_pread64+0x183/0x1c0 fs/read_write.c:626 __do_sys_pread64 fs/read_write.c:636 [inline] __se_sys_pread64 fs/read_write.c:633 [inline] __x64_sys_pread64+0x97/0xf0 fs/read_write.c:633 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Chain exists of: &sig->cred_guard_mutex --> &pipe->mutex/1 --> &p->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&p->lock); lock(&pipe->mutex/1); lock(&p->lock); lock(&sig->cred_guard_mutex); *** DEADLOCK *** 1 lock held by syz-executor1/27853: #0: 0000000027fef0d6 (&p->lock){+.+.}, at: seq_read+0x71/0x1130 fs/seq_file.c:161 stack backtrace: CPU: 0 PID: 27853 Comm: syz-executor1 Not tainted 5.0.0-rc2+ #33 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+0x1db/0x2d0 lib/dump_stack.c:113 print_circular_bug.isra.0.cold+0x1cc/0x28f kernel/locking/lockdep.c:1224 check_prev_add kernel/locking/lockdep.c:1866 [inline] check_prevs_add kernel/locking/lockdep.c:1979 [inline] validate_chain kernel/locking/lockdep.c:2350 [inline] __lock_acquire+0x3014/0x4a30 kernel/locking/lockdep.c:3338 lock_acquire+0x1db/0x570 kernel/locking/lockdep.c:3841 __mutex_lock_common kernel/locking/mutex.c:925 [inline] __mutex_lock+0x12f/0x1670 kernel/locking/mutex.c:1072 mutex_lock_killable_nested+0x16/0x20 kernel/locking/mutex.c:1102 do_io_accounting+0x1d1/0xfe0 fs/proc/base.c:2711 proc_tgid_io_accounting+0x23/0x30 fs/proc/base.c:2760 proc_single_show+0xf6/0x180 fs/proc/base.c:739 seq_read+0x4db/0x1130 fs/seq_file.c:229 __vfs_read+0x116/0xb20 fs/read_write.c:416 vfs_read+0x194/0x3e0 fs/read_write.c:452 ksys_pread64+0x183/0x1c0 fs/read_write.c:626 __do_sys_pread64 fs/read_write.c:636 [inline] __se_sys_pread64 fs/read_write.c:633 [inline] __x64_sys_pread64+0x97/0xf0 fs/read_write.c:633 do_syscall_64+0x1a3/0x800 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458099 Code: 6d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007efcc89afc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000011 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000458099 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 000000000073bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007efcc89b06d4 R13: 00000000004c4ae7 R14: 00000000004d8158 R15: 00000000ffffffff binder: 27852 RLIMIT_NICE not set binder: 27848:27856 transaction failed 29201/-71, size 0-8 line 2801 binder: 27852 RLIMIT_NICE not set kobject: 'loop4' (00000000b47dbdd9): kobject_uevent_env kobject: 'loop4' (00000000b47dbdd9): fill_kobj_path: path = '/devices/virtual/block/loop4' binder: BINDER_SET_CONTEXT_MGR already set kobject: 'loop2' (00000000e06d78fd): kobject_uevent_env kobject: 'loop2' (00000000e06d78fd): fill_kobj_path: path = '/devices/virtual/block/loop2' binder_alloc: 27848: binder_alloc_buf, no vma binder: 27848:27852 ERROR: BC_REGISTER_LOOPER called without request binder: 27848:27863 transaction failed 29189/-3, size 0-0 line 3035 binder: 27848:27856 got reply transaction with no transaction stack kobject: 'loop3' (000000007c997f1c): kobject_uevent_env kobject: 'loop3' (000000007c997f1c): fill_kobj_path: path = '/devices/virtual/block/loop3' binder: release 27848:27852 transaction 81 out, still active binder: 27852 RLIMIT_NICE not set binder: 27848:27862 ioctl 40046207 0 returned -16 binder: undelivered TRANSACTION_COMPLETE binder: 27848:27856 transaction failed 29201/-71, size 0-8 line 2801 binder: release 27848:27852 transaction 81 in, still active binder: send failed reply for transaction 81, target dead binder: undelivered TRANSACTION_ERROR: 29201 binder: undelivered TRANSACTION_ERROR: 29189 binder: undelivered TRANSACTION_ERROR: 29201 kobject: 'loop0' (000000005cebda98): kobject_uevent_env kobject: 'loop0' (000000005cebda98): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop5' (00000000cd4106e8): kobject_uevent_env kobject: 'loop5' (00000000cd4106e8): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop1' (00000000a536445c): kobject_uevent_env kobject: 'loop1' (00000000a536445c): fill_kobj_path: path = '/devices/virtual/block/loop1' binder: 27884:27889 ERROR: BC_REGISTER_LOOPER called without request binder: 27889 RLIMIT_NICE not set binder: 27889 RLIMIT_NICE not set binder: 27889 RLIMIT_NICE not set binder_alloc: 27884: binder_alloc_buf, no vma binder: 27884:27889 transaction failed 29189/-3, size 0-8 line 3035 binder: send failed reply for transaction 86 to 27884:27889 binder: undelivered TRANSACTION_COMPLETE kobject: 'loop2' (00000000e06d78fd): kobject_uevent_env kobject: 'loop2' (00000000e06d78fd): fill_kobj_path: path = '/devices/virtual/block/loop2' binder: undelivered TRANSACTION_ERROR: 29189 binder: undelivered TRANSACTION_ERROR: 29190 kobject: 'loop4' (00000000b47dbdd9): kobject_uevent_env kobject: 'loop4' (00000000b47dbdd9): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop0' (000000005cebda98): kobject_uevent_env kobject: 'loop0' (000000005cebda98): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop3' (000000007c997f1c): kobject_uevent_env kobject: 'loop3' (000000007c997f1c): fill_kobj_path: path = '/devices/virtual/block/loop3' binder: 27902:27909 ERROR: BC_REGISTER_LOOPER called without request binder: 27909 RLIMIT_NICE not set binder: 27909 RLIMIT_NICE not set binder: 27909 RLIMIT_NICE not set binder_alloc: 27902: binder_alloc_buf, no vma binder: 27902:27909 transaction failed 29189/-3, size 0-8 line 3035 binder: send failed reply for transaction 89 to 27902:27909 binder: undelivered TRANSACTION_COMPLETE binder: undelivered TRANSACTION_ERROR: 29189 binder: undelivered TRANSACTION_ERROR: 29190 kobject: 'loop0' (000000005cebda98): kobject_uevent_env kobject: 'loop0' (000000005cebda98): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop3' (000000007c997f1c): kobject_uevent_env kobject: 'loop3' (000000007c997f1c): fill_kobj_path: path = '/devices/virtual/block/loop3' kobject: 'loop1' (00000000a536445c): kobject_uevent_env kobject: 'loop1' (00000000a536445c): fill_kobj_path: path = '/devices/virtual/block/loop1' binder: 27922:27923 ERROR: BC_REGISTER_LOOPER called without request binder: 27923 RLIMIT_NICE not set binder: 27922:27937 got reply transaction with no transaction stack binder: 27922:27937 transaction failed 29201/-71, size 0-8 line 2801 kobject: 'loop3' (000000007c997f1c): kobject_uevent_env binder: release 27922:27923 transaction 92 out, still active kobject: 'loop3' (000000007c997f1c): fill_kobj_path: path = '/devices/virtual/block/loop3' binder: undelivered TRANSACTION_COMPLETE kobject: 'loop2' (00000000e06d78fd): kobject_uevent_env kobject: 'loop2' (00000000e06d78fd): fill_kobj_path: path = '/devices/virtual/block/loop2' kobject: 'loop5' (00000000cd4106e8): kobject_uevent_env kobject: 'loop5' (00000000cd4106e8): fill_kobj_path: path = '/devices/virtual/block/loop5' binder: release 27922:27923 transaction 92 in, still active kobject: 'loop0' (000000005cebda98): kobject_uevent_env binder: send failed reply for transaction 92, target dead kobject: 'loop0' (000000005cebda98): fill_kobj_path: path = '/devices/virtual/block/loop0' binder: undelivered TRANSACTION_ERROR: 29201 binder: 27951:27952 ERROR: BC_REGISTER_LOOPER called without request kobject: 'loop4' (00000000b47dbdd9): kobject_uevent_env kobject: 'loop4' (00000000b47dbdd9): fill_kobj_path: path = '/devices/virtual/block/loop4' binder_alloc: 27951: binder_alloc_buf, no vma binder: 27951:27952 transaction failed 29189/-3, size 0-8 line 3035 kobject: 'loop1' (00000000a536445c): kobject_uevent_env kobject: 'loop1' (00000000a536445c): fill_kobj_path: path = '/devices/virtual/block/loop1' binder: send failed reply for transaction 95 to 27951:27952 kobject: 'loop3' (000000007c997f1c): kobject_uevent_env kobject: 'loop3' (000000007c997f1c): fill_kobj_path: path = '/devices/virtual/block/loop3' binder: undelivered TRANSACTION_COMPLETE binder: undelivered TRANSACTION_ERROR: 29189 kobject: 'loop3' (000000007c997f1c): kobject_uevent_env binder: undelivered TRANSACTION_ERROR: 29190 kobject: 'loop3' (000000007c997f1c): fill_kobj_path: path = '/devices/virtual/block/loop3' kobject: 'loop5' (00000000cd4106e8): kobject_uevent_env kobject: 'loop5' (00000000cd4106e8): fill_kobj_path: path = '/devices/virtual/block/loop5' binder: 27981:27982 ERROR: BC_REGISTER_LOOPER called without request binder_alloc: 27981: binder_alloc_buf, no vma kobject: 'loop3' (000000007c997f1c): kobject_uevent_env binder: 27981:27982 transaction failed 29189/-3, size 0-8 line 3035 kobject: 'loop3' (000000007c997f1c): fill_kobj_path: path = '/devices/virtual/block/loop3' binder: send failed reply for transaction 98 to 27981:27982 binder: undelivered TRANSACTION_COMPLETE binder: undelivered TRANSACTION_ERROR: 29189 kobject: 'loop2' (00000000e06d78fd): kobject_uevent_env kobject: 'loop2' (00000000e06d78fd): fill_kobj_path: path = '/devices/virtual/block/loop2' binder: undelivered TRANSACTION_ERROR: 29190 kobject: 'loop5' (00000000cd4106e8): kobject_uevent_env kobject: 'loop5' (00000000cd4106e8): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop3' (000000007c997f1c): kobject_uevent_env kobject: 'loop3' (000000007c997f1c): fill_kobj_path: path = '/devices/virtual/block/loop3' binder: 28002:28003 ERROR: BC_REGISTER_LOOPER called without request kobject: 'loop3' (000000007c997f1c): kobject_uevent_env binder_alloc: 28002: binder_alloc_buf, no vma binder: 28002:28003 transaction failed 29189/-3, size 0-8 line 3035 kobject: 'loop3' (000000007c997f1c): fill_kobj_path: path = '/devices/virtual/block/loop3' binder: send failed reply for transaction 101 to 28002:28003 kobject: 'loop1' (00000000a536445c): kobject_uevent_env kobject: 'loop1' (00000000a536445c): fill_kobj_path: path = '/devices/virtual/block/loop1' binder: undelivered TRANSACTION_COMPLETE binder: undelivered TRANSACTION_ERROR: 29189 binder: undelivered TRANSACTION_ERROR: 29190 kobject: 'loop5' (00000000cd4106e8): kobject_uevent_env kobject: 'loop5' (00000000cd4106e8): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop4' (00000000b47dbdd9): kobject_uevent_env kobject: 'loop4' (00000000b47dbdd9): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop0' (000000005cebda98): kobject_uevent_env kobject: 'loop0' (000000005cebda98): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop1' (00000000a536445c): kobject_uevent_env kobject: 'loop1' (00000000a536445c): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop2' (00000000e06d78fd): kobject_uevent_env kobject: 'loop2' (00000000e06d78fd): fill_kobj_path: path = '/devices/virtual/block/loop2' kobject: 'loop3' (000000007c997f1c): kobject_uevent_env kobject: 'loop3' (000000007c997f1c): fill_kobj_path: path = '/devices/virtual/block/loop3' kobject: 'loop1' (00000000a536445c): kobject_uevent_env kobject: 'loop1' (00000000a536445c): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop2' (00000000e06d78fd): kobject_uevent_env kobject: 'loop2' (00000000e06d78fd): fill_kobj_path: path = '/devices/virtual/block/loop2' kobject: 'loop4' (00000000b47dbdd9): kobject_uevent_env kobject: 'loop4' (00000000b47dbdd9): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop5' (00000000cd4106e8): kobject_uevent_env kobject: 'loop5' (00000000cd4106e8): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop0' (000000005cebda98): kobject_uevent_env kobject: 'loop0' (000000005cebda98): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop1' (00000000a536445c): kobject_uevent_env kobject: 'loop1' (00000000a536445c): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop1' (00000000a536445c): kobject_uevent_env kobject: 'loop1' (00000000a536445c): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop4' (00000000b47dbdd9): kobject_uevent_env kobject: 'loop4' (00000000b47dbdd9): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop1' (00000000a536445c): kobject_uevent_env kobject: 'loop1' (00000000a536445c): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop1' (00000000a536445c): kobject_uevent_env kobject: 'loop1' (00000000a536445c): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop3' (000000007c997f1c): kobject_uevent_env kobject: 'loop3' (000000007c997f1c): fill_kobj_path: path = '/devices/virtual/block/loop3' kobject: 'hci0' (000000002709fbe4): kobject_add_internal: parent: 'bluetooth', set: 'devices' kobject: 'hci0' (000000002709fbe4): kobject_uevent_env kobject: 'hci0' (000000002709fbe4): fill_kobj_path: path = '/devices/virtual/bluetooth/hci0' kobject: 'rfkill37' (00000000208a8295): kobject_add_internal: parent: 'hci0', set: 'devices' kobject: 'rfkill37' (00000000208a8295): kobject_uevent_env kobject: 'rfkill37' (00000000208a8295): fill_kobj_path: path = '/devices/virtual/bluetooth/hci0/rfkill37' kobject: 'loop3' (000000007c997f1c): kobject_uevent_env kobject: 'loop3' (000000007c997f1c): fill_kobj_path: path = '/devices/virtual/block/loop3' kobject: 'loop2' (00000000e06d78fd): kobject_uevent_env kobject: 'loop2' (00000000e06d78fd): fill_kobj_path: path = '/devices/virtual/block/loop2' kobject: 'loop0' (000000005cebda98): kobject_uevent_env kobject: 'loop0' (000000005cebda98): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop4' (00000000b47dbdd9): kobject_uevent_env kobject: 'loop4' (00000000b47dbdd9): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop4' (00000000b47dbdd9): kobject_uevent_env kobject: 'loop4' (00000000b47dbdd9): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop2' (00000000e06d78fd): kobject_uevent_env kobject: 'loop2' (00000000e06d78fd): fill_kobj_path: path = '/devices/virtual/block/loop2' kobject: 'loop3' (000000007c997f1c): kobject_uevent_env kobject: 'loop3' (000000007c997f1c): fill_kobj_path: path = '/devices/virtual/block/loop3'