====================================================== WARNING: possible circular locking dependency detected 4.14.0+ #183 Not tainted ------------------------------------------------------ syz-executor4/9377 is trying to acquire lock: (console_lock){+.+.}, at: [] vcs_read+0x129/0xae0 drivers/tty/vt/vc_screen.c:219 but task is already holding lock: (&pipe->mutex/1){+.+.}, at: [] pipe_lock_nested fs/pipe.c:67 [inline] (&pipe->mutex/1){+.+.}, at: [] pipe_lock+0x56/0x70 fs/pipe.c:75 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&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 -> #2 (sb_writers){.+.+}: spin_lock include/linux/spinlock.h:315 [inline] fast_dput fs/dcache.c:687 [inline] dput.part.23+0x492/0x830 fs/dcache.c:794 -> #1 ((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 vcs_make_sysfs+0x35/0x60 drivers/tty/vt/vc_screen.c:629 vc_allocate+0x4b7/0x6b0 drivers/tty/vt/vt.c:797 con_install+0x52/0x440 drivers/tty/vt/vt.c:2876 tty_driver_install_tty drivers/tty/tty_io.c:1215 [inline] tty_init_dev+0xf6/0x4a0 drivers/tty/tty_io.c:1315 tty_open_by_driver drivers/tty/tty_io.c:1942 [inline] tty_open+0x608/0xab0 drivers/tty/tty_io.c:1990 chrdev_open+0x257/0x730 fs/char_dev.c:417 do_dentry_open+0x682/0xd70 fs/open.c:752 vfs_open+0x107/0x230 fs/open.c:866 do_last fs/namei.c:3388 [inline] path_openat+0x1157/0x3530 fs/namei.c:3528 do_filp_open+0x25b/0x3b0 fs/namei.c:3563 do_sys_open+0x502/0x6d0 fs/open.c:1059 SYSC_open fs/open.c:1077 [inline] SyS_open+0x2d/0x40 fs/open.c:1072 entry_SYSCALL_64_fastpath+0x1f/0x96 -> #0 (console_lock){+.+.}: 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 console_lock+0x4b/0x80 kernel/printk/printk.c:2047 vcs_read+0x129/0xae0 drivers/tty/vt/vc_screen.c:219 do_loop_readv_writev fs/read_write.c:673 [inline] do_iter_read+0x3db/0x5b0 fs/read_write.c:897 vfs_readv+0x121/0x1c0 fs/read_write.c:959 kernel_readv fs/splice.c:361 [inline] default_file_splice_read+0x508/0xae0 fs/splice.c:416 do_splice_to+0x110/0x170 fs/splice.c:880 do_splice fs/splice.c:1173 [inline] SYSC_splice fs/splice.c:1402 [inline] SyS_splice+0x11a8/0x1630 fs/splice.c:1382 entry_SYSCALL_64_fastpath+0x1f/0x96 other info that might help us debug this: Chain exists of: console_lock --> sb_writers --> &pipe->mutex/1 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&pipe->mutex/1); lock(sb_writers); lock(&pipe->mutex/1); lock(console_lock); *** DEADLOCK *** 1 lock held by syz-executor4/9377: #0: (&pipe->mutex/1){+.+.}, at: [] pipe_lock_nested fs/pipe.c:67 [inline] #0: (&pipe->mutex/1){+.+.}, at: [] pipe_lock+0x56/0x70 fs/pipe.c:75 stack backtrace: CPU: 0 PID: 9377 Comm: syz-executor4 Not tainted 4.14.0+ #183 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 console_lock+0x4b/0x80 kernel/printk/printk.c:2047 vcs_read+0x129/0xae0 drivers/tty/vt/vc_screen.c:219 do_loop_readv_writev fs/read_write.c:673 [inline] do_iter_read+0x3db/0x5b0 fs/read_write.c:897 vfs_readv+0x121/0x1c0 fs/read_write.c:959 kernel_readv fs/splice.c:361 [inline] default_file_splice_read+0x508/0xae0 fs/splice.c:416 do_splice_to+0x110/0x170 fs/splice.c:880 do_splice fs/splice.c:1173 [inline] SYSC_splice fs/splice.c:1402 [inline] SyS_splice+0x11a8/0x1630 fs/splice.c:1382 entry_SYSCALL_64_fastpath+0x1f/0x96 RIP: 0033:0x452879 RSP: 002b:00007f9244adcbe8 EFLAGS: 00000212 ORIG_RAX: 0000000000000113 RAX: ffffffffffffffda RBX: 0000000000758020 RCX: 0000000000452879 RDX: 0000000000000017 RSI: 0000000000000000 RDI: 0000000000000013 RBP: 0000000000000086 R08: 0000000000000003 R09: 0000000000000008 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f4d68 R13: 00000000ffffffff R14: 00007f9244add6d4 R15: 0000000000000000 device gre0 entered promiscuous mode nla_parse: 10 callbacks suppressed netlink: 5 bytes leftover after parsing attributes in process `syz-executor5'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor7'. QAT: failed to copy from user cfg_data. netlink: 5 bytes leftover after parsing attributes in process `syz-executor5'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor7'. QAT: failed to copy from user cfg_data. netlink: 8 bytes leftover after parsing attributes in process `syz-executor7'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor7'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor7'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor7'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor1'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor7'. kvm_set_msr_common: 16 callbacks suppressed kvm [9627]: vcpu0, guest rIP: 0x27 disabled perfctr wrmsr: 0xc1 data 0xffffffff audit: type=1326 audit(1510989385.924:6886): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=9627 comm="syz-executor6" exe="/root/syz-executor6" sig=31 arch=c000003e syscall=202 compat=0 ip=0x452879 code=0xffff0000 kvm [9627]: vcpu0, guest rIP: 0x0 disabled perfctr wrmsr: 0xc1 data 0xffffffff audit: type=1326 audit(1510989386.229:6887): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=9627 comm="syz-executor6" exe="/root/syz-executor6" sig=31 arch=c000003e syscall=202 compat=0 ip=0x452879 code=0xffff0000 kvm [9714]: vcpu0, guest rIP: 0x27 disabled perfctr wrmsr: 0xc1 data 0xffffffff audit: type=1326 audit(1510989386.492:6888): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=9714 comm="syz-executor6" exe="/root/syz-executor6" sig=31 arch=c000003e syscall=202 compat=0 ip=0x452879 code=0xffff0000 kvm [9714]: vcpu0, guest rIP: 0x27 disabled perfctr wrmsr: 0xc1 data 0xffffffff audit: type=1326 audit(1510989386.578:6889): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=9714 comm="syz-executor6" exe="/root/syz-executor6" sig=31 arch=c000003e syscall=202 compat=0 ip=0x452879 code=0xffff0000 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=27 sclass=netlink_route_socket pig=9937 comm=syz-executor7 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=27 sclass=netlink_route_socket pig=9928 comm=syz-executor7 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 1 CPU: 0 PID: 10402 Comm: syz-executor7 Not tainted 4.14.0+ #183 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 fail_dump lib/fault-inject.c:51 [inline] should_fail+0x8c0/0xa40 lib/fault-inject.c:149 should_failslab+0xec/0x120 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc_node mm/slab.c:3292 [inline] kmem_cache_alloc_node+0x56/0x760 mm/slab.c:3635 __alloc_skb+0xf1/0x780 net/core/skbuff.c:193 alloc_skb include/linux/skbuff.h:981 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1144 [inline] netlink_sendmsg+0xa86/0xe70 net/netlink/af_netlink.c:1836 sock_sendmsg_nosec net/socket.c:632 [inline] sock_sendmsg+0xca/0x110 net/socket.c:642 sock_write_iter+0x320/0x5e0 net/socket.c:911 call_write_iter include/linux/fs.h:1772 [inline] new_sync_write fs/read_write.c:469 [inline] __vfs_write+0x68a/0x970 fs/read_write.c:482 vfs_write+0x18f/0x510 fs/read_write.c:544 SYSC_write fs/read_write.c:589 [inline] SyS_write+0xef/0x220 fs/read_write.c:581 entry_SYSCALL_64_fastpath+0x1f/0x96 RIP: 0033:0x452879 RSP: 002b:00007f139ee03be8 EFLAGS: 00000212 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00000000007580d8 RCX: 0000000000452879 RDX: 0000000000000024 RSI: 0000000020ab4000 RDI: 0000000000000013 RBP: 00007f139ee03a20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000004b757e R13: 00007f139ee03b58 R14: 00000000004b758e R15: 0000000000000000 nla_parse: 158 callbacks suppressed netlink: 8 bytes leftover after parsing attributes in process `syz-executor7'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor6'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor6'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor7'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor7'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor7'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor7'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor7'. Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable netlink: 8 bytes leftover after parsing attributes in process `syz-executor7'. QAT: Invalid ioctl netlink: 8 bytes leftover after parsing attributes in process `syz-executor7'. QAT: Invalid ioctl QAT: Invalid ioctl QAT: Invalid ioctl FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 1 PID: 11265 Comm: syz-executor5 Not tainted 4.14.0+ #183 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 fail_dump lib/fault-inject.c:51 [inline] should_fail+0x8c0/0xa40 lib/fault-inject.c:149 should_failslab+0xec/0x120 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3371 [inline] kmem_cache_alloc+0x47/0x760 mm/slab.c:3545 aio_get_req fs/aio.c:1033 [inline] io_submit_one fs/aio.c:1562 [inline] do_io_submit+0x353/0x14f0 fs/aio.c:1682 SYSC_io_submit fs/aio.c:1707 [inline] SyS_io_submit+0x27/0x30 fs/aio.c:1704 entry_SYSCALL_64_fastpath+0x1f/0x96 RIP: 0033:0x452879 RSP: 002b:00007fd40afb4be8 EFLAGS: 00000212 ORIG_RAX: 00000000000000d1 RAX: ffffffffffffffda RBX: 00000000007580d8 RCX: 0000000000452879 RDX: 0000000020103000 RSI: 0000000000000001 RDI: 00007fd40afb6000 RBP: 00007fd40afb4a20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000004b757e R13: 00007fd40afb4b58 R14: 00000000004b758e R15: 0000000000000000 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 0 PID: 11418 Comm: syz-executor4 Not tainted 4.14.0+ #183 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 fail_dump lib/fault-inject.c:51 [inline] should_fail+0x8c0/0xa40 lib/fault-inject.c:149 should_failslab+0xec/0x120 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3371 [inline] kmem_cache_alloc+0x47/0x760 mm/slab.c:3545 aio_get_req fs/aio.c:1033 [inline] io_submit_one fs/aio.c:1562 [inline] do_io_submit+0x353/0x14f0 fs/aio.c:1682 SYSC_io_submit fs/aio.c:1707 [inline] SyS_io_submit+0x27/0x30 fs/aio.c:1704 entry_SYSCALL_64_fastpath+0x1f/0x96 RIP: 0033:0x452879 RSP: 002b:00007f9244ababe8 EFLAGS: 00000212 ORIG_RAX: 00000000000000d1 RAX: ffffffffffffffda RBX: 00000000007580d8 RCX: 0000000000452879 RDX: 0000000020103000 RSI: 0000000000000001 RDI: 00007f9244abc000 RBP: 00007f9244abaa20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000004b757e R13: 00007f9244abab58 R14: 00000000004b758e R15: 0000000000000000 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 0 PID: 11647 Comm: syz-executor3 Not tainted 4.14.0+ #183 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 fail_dump lib/fault-inject.c:51 [inline] should_fail+0x8c0/0xa40 lib/fault-inject.c:149 should_failslab+0xec/0x120 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3371 [inline] kmem_cache_alloc+0x47/0x760 mm/slab.c:3545 kmem_cache_zalloc include/linux/slab.h:678 [inline] mmu_topup_memory_cache arch/x86/kvm/mmu.c:865 [inline] mmu_topup_memory_caches+0xd2/0x310 arch/x86/kvm/mmu.c:911 kvm_mmu_load+0x21/0xf90 arch/x86/kvm/mmu.c:4635 kvm_mmu_reload arch/x86/kvm/mmu.h:85 [inline] vcpu_enter_guest arch/x86/kvm/x86.c:6930 [inline] vcpu_run arch/x86/kvm/x86.c:7127 [inline] kvm_arch_vcpu_ioctl_run+0x2e6f/0x5d20 arch/x86/kvm/x86.c:7297 kvm_vcpu_ioctl+0x64c/0x1010 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2551 vfs_ioctl fs/ioctl.c:46 [inline] do_vfs_ioctl+0x1b1/0x1530 fs/ioctl.c:686 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 entry_SYSCALL_64_fastpath+0x1f/0x96 RIP: 0033:0x452879 RSP: 002b:00007fdf009f0be8 EFLAGS: 00000212 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000758020 RCX: 0000000000452879 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000016 RBP: 00007fdf009f0a20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000004b757e R13: 00007fdf009f0b58 R14: 00000000004b758e R15: 0000000000000000 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 1 PID: 11677 Comm: syz-executor3 Not tainted 4.14.0+ #183 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 fail_dump lib/fault-inject.c:51 [inline] should_fail+0x8c0/0xa40 lib/fault-inject.c:149 should_failslab+0xec/0x120 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3371 [inline] kmem_cache_alloc+0x47/0x760 mm/slab.c:3545 kmem_cache_zalloc include/linux/slab.h:678 [inline] mmu_topup_memory_cache arch/x86/kvm/mmu.c:865 [inline] mmu_topup_memory_caches+0xd2/0x310 arch/x86/kvm/mmu.c:911 kvm_mmu_load+0x21/0xf90 arch/x86/kvm/mmu.c:4635 kvm_mmu_reload arch/x86/kvm/mmu.h:85 [inline] vcpu_enter_guest arch/x86/kvm/x86.c:6930 [inline] vcpu_run arch/x86/kvm/x86.c:7127 [inline] kvm_arch_vcpu_ioctl_run+0x2e6f/0x5d20 arch/x86/kvm/x86.c:7297 kvm_vcpu_ioctl+0x64c/0x1010 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2551 vfs_ioctl fs/ioctl.c:46 [inline] do_vfs_ioctl+0x1b1/0x1530 fs/ioctl.c:686 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 entry_SYSCALL_64_fastpath+0x1f/0x96 RIP: 0033:0x452879 RSP: 002b:00007fdf009f0be8 EFLAGS: 00000212 ORIG_RAX: 0000000000000010