====================================================== WARNING: possible circular locking dependency detected 4.14.0+ #191 Not tainted ------------------------------------------------------ syz-executor3/12181 is trying to acquire lock: (&sb->s_type->i_mutex_key#10){++++}, at: [] inode_lock include/linux/fs.h:713 [inline] (&sb->s_type->i_mutex_key#10){++++}, at: [] generic_file_write_iter+0xdc/0x7a0 mm/filemap.c:3289 but task is already holding lock: (&pipe->mutex/1){+.+.}, at: [] pipe_lock_nested fs/pipe.c:67 [inline] (&pipe->mutex/1){+.+.}, at: [] pipe_lock fs/pipe.c:75 [inline] (&pipe->mutex/1){+.+.}, at: [] pipe_wait+0x1e6/0x280 fs/pipe.c:123 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (&pipe->mutex/1){+.+.}: lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4004 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 pipe_lock_nested fs/pipe.c:67 [inline] pipe_lock+0x56/0x70 fs/pipe.c:75 iter_file_splice_write+0x264/0xf30 fs/splice.c:699 do_splice_from fs/splice.c:851 [inline] do_splice fs/splice.c:1147 [inline] SYSC_splice fs/splice.c:1402 [inline] SyS_splice+0x7d5/0x1630 fs/splice.c:1382 entry_SYSCALL_64_fastpath+0x1f/0x96 -> #5 (sb_writers){.+.+}: spin_lock include/linux/spinlock.h:315 [inline] inode_free_security security/selinux/hooks.c:347 [inline] selinux_inode_free_security+0x12a/0x410 security/selinux/hooks.c:2890 -> #4 ((completion)&req.done){+.+.}: lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4004 complete_acquire include/linux/completion.h:40 [inline] __wait_for_common kernel/sched/completion.c:109 [inline] wait_for_common kernel/sched/completion.c:123 [inline] wait_for_completion+0xcb/0x7b0 kernel/sched/completion.c:144 devtmpfs_create_node+0x32b/0x4a0 drivers/base/devtmpfs.c:115 device_add+0x120f/0x1640 drivers/base/core.c:1824 device_create_groups_vargs+0x1f3/0x250 drivers/base/core.c:2430 device_create_vargs drivers/base/core.c:2470 [inline] device_create+0xda/0x110 drivers/base/core.c:2506 msr_device_create+0x26/0x40 arch/x86/kernel/msr.c:188 cpuhp_invoke_callback+0x2ea/0x1d20 kernel/cpu.c:182 cpuhp_thread_fun+0x48e/0x7e0 kernel/cpu.c:571 smpboot_thread_fn+0x450/0x7c0 kernel/smpboot.c:164 kthread+0x37a/0x440 kernel/kthread.c:238 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:437 -> #3 (cpuhp_state-up){+.+.}: lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4004 cpuhp_lock_acquire kernel/cpu.c:85 [inline] cpuhp_invoke_ap_callback kernel/cpu.c:605 [inline] cpuhp_issue_call+0x1e5/0x520 kernel/cpu.c:1495 __cpuhp_setup_state_cpuslocked+0x282/0x600 kernel/cpu.c:1642 __cpuhp_setup_state+0xb0/0x140 kernel/cpu.c:1671 cpuhp_setup_state include/linux/cpuhotplug.h:201 [inline] page_writeback_init+0x4d/0x71 mm/page-writeback.c:2083 pagecache_init+0x48/0x4f mm/filemap.c:977 start_kernel+0x6bc/0x74f init/main.c:690 x86_64_start_reservations+0x2a/0x2c arch/x86/kernel/head64.c:378 x86_64_start_kernel+0x77/0x7a arch/x86/kernel/head64.c:359 secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:237 -> #2 (cpuhp_state_mutex){+.+.}: lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4004 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 __cpuhp_setup_state_cpuslocked+0x5b/0x600 kernel/cpu.c:1617 __cpuhp_setup_state+0xb0/0x140 kernel/cpu.c:1671 cpuhp_setup_state_nocalls include/linux/cpuhotplug.h:229 [inline] kvm_guest_init+0x1f3/0x20f arch/x86/kernel/kvm.c:528 setup_arch+0x17e8/0x1a02 arch/x86/kernel/setup.c:1266 start_kernel+0xa5/0x74f init/main.c:530 x86_64_start_reservations+0x2a/0x2c arch/x86/kernel/head64.c:378 x86_64_start_kernel+0x77/0x7a arch/x86/kernel/head64.c:359 secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:237 -> #1 (cpu_hotplug_lock.rw_sem){++++}: lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4004 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:36 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] cpus_read_lock+0x42/0x90 kernel/cpu.c:293 get_online_cpus include/linux/cpu.h:117 [inline] lru_add_drain_all+0xe/0x20 mm/swap.c:729 shmem_wait_for_pins mm/shmem.c:2672 [inline] shmem_add_seals+0x3df/0x1060 mm/shmem.c:2780 shmem_fcntl+0xfe/0x130 mm/shmem.c:2815 do_fcntl+0x73e/0x1160 fs/fcntl.c:421 SYSC_fcntl fs/fcntl.c:463 [inline] SyS_fcntl+0xdc/0x120 fs/fcntl.c:448 entry_SYSCALL_64_fastpath+0x1f/0x96 -> #0 (&sb->s_type->i_mutex_key#10){++++}: check_prevs_add kernel/locking/lockdep.c:2031 [inline] validate_chain kernel/locking/lockdep.c:2473 [inline] __lock_acquire+0x3498/0x47f0 kernel/locking/lockdep.c:3500 lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4004 down_write+0x87/0x120 kernel/locking/rwsem.c:70 inode_lock include/linux/fs.h:713 [inline] generic_file_write_iter+0xdc/0x7a0 mm/filemap.c:3289 call_write_iter include/linux/fs.h:1772 [inline] do_iter_readv_writev+0x531/0x7f0 fs/read_write.c:653 do_iter_write+0x15a/0x540 fs/read_write.c:932 vfs_iter_write+0x77/0xb0 fs/read_write.c:945 iter_file_splice_write+0x7db/0xf30 fs/splice.c:749 do_splice_from fs/splice.c:851 [inline] do_splice fs/splice.c:1147 [inline] SYSC_splice fs/splice.c:1402 [inline] SyS_splice+0x7d5/0x1630 fs/splice.c:1382 entry_SYSCALL_64_fastpath+0x1f/0x96 other info that might help us debug this: Chain exists of: &sb->s_type->i_mutex_key#10 --> sb_writers --> &pipe->mutex/1 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&pipe->mutex/1); lock(sb_writers); lock(&pipe->mutex/1); lock(&sb->s_type->i_mutex_key#10); *** DEADLOCK *** 2 locks held by syz-executor3/12181: #0: (sb_writers#5){.+.+}, at: [] file_start_write include/linux/fs.h:2715 [inline] #0: (sb_writers#5){.+.+}, at: [] do_splice fs/splice.c:1146 [inline] #0: (sb_writers#5){.+.+}, at: [] SYSC_splice fs/splice.c:1402 [inline] #0: (sb_writers#5){.+.+}, at: [] SyS_splice+0x1117/0x1630 fs/splice.c:1382 #1: (&pipe->mutex/1){+.+.}, at: [] pipe_lock_nested fs/pipe.c:67 [inline] #1: (&pipe->mutex/1){+.+.}, at: [] pipe_lock fs/pipe.c:75 [inline] #1: (&pipe->mutex/1){+.+.}, at: [] pipe_wait+0x1e6/0x280 fs/pipe.c:123 stack backtrace: CPU: 1 PID: 12181 Comm: syz-executor3 Not tainted 4.14.0+ #191 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+0x194/0x257 lib/dump_stack.c:53 print_circular_bug+0x42d/0x610 kernel/locking/lockdep.c:1271 check_prev_add+0x666/0x15f0 kernel/locking/lockdep.c:1914 check_prevs_add kernel/locking/lockdep.c:2031 [inline] validate_chain kernel/locking/lockdep.c:2473 [inline] __lock_acquire+0x3498/0x47f0 kernel/locking/lockdep.c:3500 lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4004 down_write+0x87/0x120 kernel/locking/rwsem.c:70 inode_lock include/linux/fs.h:713 [inline] generic_file_write_iter+0xdc/0x7a0 mm/filemap.c:3289 call_write_iter include/linux/fs.h:1772 [inline] do_iter_readv_writev+0x531/0x7f0 fs/read_write.c:653 do_iter_write+0x15a/0x540 fs/read_write.c:932 vfs_iter_write+0x77/0xb0 fs/read_write.c:945 iter_file_splice_write+0x7db/0xf30 fs/splice.c:749 do_splice_from fs/splice.c:851 [inline] do_splice fs/splice.c:1147 [inline] SYSC_splice fs/splice.c:1402 [inline] SyS_splice+0x7d5/0x1630 fs/splice.c:1382 entry_SYSCALL_64_fastpath+0x1f/0x96 RIP: 0033:0x452879 RSP: 002b:00007f698d591be8 EFLAGS: 00000212 ORIG_RAX: 0000000000000113 RAX: ffffffffffffffda RBX: 00000000007580d8 RCX: 0000000000452879 RDX: 0000000000000019 RSI: 0000000000000000 RDI: 0000000000000017 RBP: 0000000000000086 R08: 00000000fffffffe R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000 R13: 0000000000a6f7ff R14: 00007f698d5929c0 R15: 0000000000000010 device gre0 entered promiscuous mode kauditd_printk_skb: 63 callbacks suppressed audit: type=1326 audit(1511491713.379:745): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=12265 comm="syz-executor2" exe="/root/syz-executor2" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452879 code=0x7ffc0000 audit: type=1326 audit(1511491713.379:746): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=12265 comm="syz-executor2" exe="/root/syz-executor2" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452879 code=0x7ffc0000 audit: type=1326 audit(1511491713.388:747): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=12265 comm="syz-executor2" exe="/root/syz-executor2" sig=0 arch=c000003e syscall=224 compat=0 ip=0x452879 code=0x7ffc0000 audit: type=1326 audit(1511491713.388:748): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=12265 comm="syz-executor2" exe="/root/syz-executor2" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452879 code=0x7ffc0000 audit: type=1326 audit(1511491713.388:749): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=12265 comm="syz-executor2" exe="/root/syz-executor2" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452879 code=0x7ffc0000 audit: type=1326 audit(1511491713.389:750): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=12265 comm="syz-executor2" exe="/root/syz-executor2" sig=0 arch=c000003e syscall=41 compat=0 ip=0x452879 code=0x7ffc0000 audit: type=1326 audit(1511491713.389:751): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=12265 comm="syz-executor2" exe="/root/syz-executor2" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452879 code=0x7ffc0000 audit: type=1326 audit(1511491713.389:752): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=12265 comm="syz-executor2" exe="/root/syz-executor2" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452879 code=0x7ffc0000 audit: type=1326 audit(1511491713.389:753): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=12265 comm="syz-executor2" exe="/root/syz-executor2" sig=0 arch=c000003e syscall=72 compat=0 ip=0x452879 code=0x7ffc0000 audit: type=1326 audit(1511491713.389:754): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=12265 comm="syz-executor2" exe="/root/syz-executor2" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452879 code=0x7ffc0000 device lo entered promiscuous mode IPv6: ADDRCONF(NETDEV_CHANGE): lo: link becomes ready device lo left promiscuous mode device lo entered promiscuous mode IPv6: ADDRCONF(NETDEV_CHANGE): lo: link becomes ready device lo left promiscuous mode SELinux: unrecognized netlink message: protocol=0 nlmsg_type=3 sclass=netlink_route_socket pig=12644 comm=syz-executor7 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=12644 comm=syz-executor7 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=51 sclass=netlink_route_socket pig=12644 comm=syz-executor7 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=12662 comm=syz-executor7 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=12662 comm=syz-executor7 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=3 sclass=netlink_route_socket pig=12644 comm=syz-executor7 nla_parse: 6 callbacks suppressed netlink: 64 bytes leftover after parsing attributes in process `syz-executor3'. SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=12644 comm=syz-executor7 netlink: 64 bytes leftover after parsing attributes in process `syz-executor3'. SELinux: unrecognized netlink message: protocol=0 nlmsg_type=51 sclass=netlink_route_socket pig=12662 comm=syz-executor7 netlink: 1 bytes leftover after parsing attributes in process `syz-executor3'. netlink: 1 bytes leftover after parsing attributes in process `syz-executor3'. dccp_invalid_packet: P.CsCov 5 exceeds packet length 552 dccp_invalid_packet: P.CsCov 5 exceeds packet length 552 netlink: 9 bytes leftover after parsing attributes in process `syz-executor0'. netlink: 9 bytes leftover after parsing attributes in process `syz-executor0'. netlink: 9 bytes leftover after parsing attributes in process `syz-executor0'. netlink: 1 bytes leftover after parsing attributes in process `syz-executor7'. netlink: 1 bytes leftover after parsing attributes in process `syz-executor7'. netlink: 9 bytes leftover after parsing attributes in process `syz-executor0'. device gre0 entered promiscuous mode QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl device gre0 entered promiscuous mode device syz2 entered promiscuous mode QAT: Invalid ioctl QAT: Invalid ioctl selinux_nlmsg_perm: 2 callbacks suppressed SELinux: unrecognized netlink message: protocol=0 nlmsg_type=3 sclass=netlink_route_socket pig=13323 comm=syz-executor4 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=13323 comm=syz-executor4 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=3 sclass=netlink_route_socket pig=13323 comm=syz-executor4 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=13323 comm=syz-executor4 device syz2 left promiscuous mode ALSA: seq fatal error: cannot create timer (-19) ALSA: seq fatal error: cannot create timer (-19) Empty option to dns_resolver key Empty option to dns_resolver key nla_parse: 4 callbacks suppressed netlink: 5 bytes leftover after parsing attributes in process `syz-executor0'. netlink: 5 bytes leftover after parsing attributes in process `syz-executor0'.