====================================================== WARNING: possible circular locking dependency detected 4.14.166-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.4/9222 is trying to acquire lock: (&sig->cred_guard_mutex){+.+.}, at: [] do_io_accounting+0x1d6/0x7b0 fs/proc/base.c:2726 but task is already holding lock: (&p->lock){+.+.}, at: [] seq_read+0xc1/0x1280 fs/seq_file.c:165 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&p->lock){+.+.}: lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xe8/0x1470 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 seq_read+0xc1/0x1280 fs/seq_file.c:165 do_loop_readv_writev fs/read_write.c:695 [inline] do_loop_readv_writev fs/read_write.c:682 [inline] do_iter_read+0x3e2/0x5b0 fs/read_write.c:919 vfs_readv+0xd3/0x130 fs/read_write.c:981 kernel_readv fs/splice.c:361 [inline] default_file_splice_read+0x421/0x870 fs/splice.c:416 do_splice_to+0x105/0x170 fs/splice.c:880 splice_direct_to_actor+0x222/0x7b0 fs/splice.c:952 do_splice_direct+0x18d/0x230 fs/splice.c:1061 do_sendfile+0x4db/0xbd0 fs/read_write.c:1441 SYSC_sendfile64 fs/read_write.c:1502 [inline] SyS_sendfile64+0x102/0x110 fs/read_write.c:1488 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 -> #2 (sb_writers#4){.+.+}: lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:36 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] __sb_start_write+0x1ae/0x2f0 fs/super.c:1363 sb_start_write include/linux/fs.h:1548 [inline] mnt_want_write+0x3f/0xb0 fs/namespace.c:386 ovl_want_write+0x76/0xa0 fs/overlayfs/util.c:25 ovl_xattr_set+0x4f/0x270 fs/overlayfs/inode.c:214 ovl_posix_acl_xattr_set+0x3f9/0x830 fs/overlayfs/super.c:762 __vfs_setxattr+0xd8/0x130 fs/xattr.c:150 __vfs_setxattr_noperm+0x102/0x3c0 fs/xattr.c:181 vfs_setxattr+0xc5/0xf0 fs/xattr.c:224 setxattr+0x1de/0x350 fs/xattr.c:453 path_setxattr+0x11f/0x140 fs/xattr.c:472 SYSC_lsetxattr fs/xattr.c:494 [inline] SyS_lsetxattr+0x38/0x50 fs/xattr.c:490 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 -> #1 (&ovl_i_mutex_dir_key[depth]){++++}: lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994 down_read+0x3b/0xb0 kernel/locking/rwsem.c:24 inode_lock_shared include/linux/fs.h:728 [inline] do_last fs/namei.c:3330 [inline] path_openat+0x191c/0x3f70 fs/namei.c:3566 do_filp_open+0x18e/0x250 fs/namei.c:3600 do_open_execat+0xe7/0x4a0 fs/exec.c:849 do_execveat_common.isra.0+0x6d5/0x1dd0 fs/exec.c:1740 do_execve fs/exec.c:1847 [inline] SYSC_execve fs/exec.c:1928 [inline] SyS_execve+0x39/0x50 fs/exec.c:1923 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 -> #0 (&sig->cred_guard_mutex){+.+.}: check_prev_add kernel/locking/lockdep.c:1901 [inline] check_prevs_add kernel/locking/lockdep.c:2018 [inline] validate_chain kernel/locking/lockdep.c:2460 [inline] __lock_acquire+0x2cb3/0x4620 kernel/locking/lockdep.c:3487 lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xe8/0x1470 kernel/locking/mutex.c:893 mutex_lock_killable_nested+0x16/0x20 kernel/locking/mutex.c:923 do_io_accounting+0x1d6/0x7b0 fs/proc/base.c:2726 proc_tgid_io_accounting+0x23/0x30 fs/proc/base.c:2775 proc_single_show+0xf0/0x160 fs/proc/base.c:761 seq_read+0x51a/0x1280 fs/seq_file.c:237 do_loop_readv_writev fs/read_write.c:695 [inline] do_loop_readv_writev fs/read_write.c:682 [inline] do_iter_read+0x3e2/0x5b0 fs/read_write.c:919 vfs_readv+0xd3/0x130 fs/read_write.c:981 kernel_readv fs/splice.c:361 [inline] default_file_splice_read+0x421/0x870 fs/splice.c:416 do_splice_to+0x105/0x170 fs/splice.c:880 splice_direct_to_actor+0x222/0x7b0 fs/splice.c:952 do_splice_direct+0x18d/0x230 fs/splice.c:1061 do_sendfile+0x4db/0xbd0 fs/read_write.c:1441 SYSC_sendfile64 fs/read_write.c:1502 [inline] SyS_sendfile64+0x102/0x110 fs/read_write.c:1488 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 other info that might help us debug this: Chain exists of: &sig->cred_guard_mutex --> sb_writers#4 --> &p->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&p->lock); lock(sb_writers#4); lock(&p->lock); lock(&sig->cred_guard_mutex); *** DEADLOCK *** 2 locks held by syz-executor.4/9222: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2707 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x912/0xbd0 fs/read_write.c:1440 #1: (&p->lock){+.+.}, at: [] seq_read+0xc1/0x1280 fs/seq_file.c:165 stack backtrace: CPU: 0 PID: 9222 Comm: syz-executor.4 Not tainted 4.14.166-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+0x142/0x197 lib/dump_stack.c:58 print_circular_bug.isra.0.cold+0x1cc/0x28f kernel/locking/lockdep.c:1258 check_prev_add kernel/locking/lockdep.c:1901 [inline] check_prevs_add kernel/locking/lockdep.c:2018 [inline] validate_chain kernel/locking/lockdep.c:2460 [inline] __lock_acquire+0x2cb3/0x4620 kernel/locking/lockdep.c:3487 lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3994 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xe8/0x1470 kernel/locking/mutex.c:893 mutex_lock_killable_nested+0x16/0x20 kernel/locking/mutex.c:923 do_io_accounting+0x1d6/0x7b0 fs/proc/base.c:2726 proc_tgid_io_accounting+0x23/0x30 fs/proc/base.c:2775 proc_single_show+0xf0/0x160 fs/proc/base.c:761 seq_read+0x51a/0x1280 fs/seq_file.c:237 do_loop_readv_writev fs/read_write.c:695 [inline] do_loop_readv_writev fs/read_write.c:682 [inline] do_iter_read+0x3e2/0x5b0 fs/read_write.c:919 vfs_readv+0xd3/0x130 fs/read_write.c:981 kernel_readv fs/splice.c:361 [inline] default_file_splice_read+0x421/0x870 fs/splice.c:416 do_splice_to+0x105/0x170 fs/splice.c:880 splice_direct_to_actor+0x222/0x7b0 fs/splice.c:952 do_splice_direct+0x18d/0x230 fs/splice.c:1061 do_sendfile+0x4db/0xbd0 fs/read_write.c:1441 SYSC_sendfile64 fs/read_write.c:1502 [inline] SyS_sendfile64+0x102/0x110 fs/read_write.c:1488 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45b349 RSP: 002b:00007f726a786c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f726a7876d4 RCX: 000000000045b349 RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000004 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000209 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000008a6 R14: 00000000004ca018 R15: 000000000075bf2c overlayfs: upperdir is in-use by another mount, mount with '-o index=off' to override exclusive upperdir protection. SELinux: unrecognized netlink message: protocol=0 nlmsg_type=2394 sclass=netlink_route_socket pig=9337 comm=syz-executor.5 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=9482 comm=syz-executor.0 nla_parse: 10 callbacks suppressed netlink: 2212 bytes leftover after parsing attributes in process `syz-executor.0'. SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=9482 comm=syz-executor.0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=9482 comm=syz-executor.0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=9482 comm=syz-executor.0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=9482 comm=syz-executor.0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=9482 comm=syz-executor.0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=9482 comm=syz-executor.0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=9482 comm=syz-executor.0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=9482 comm=syz-executor.0 usb usb9: Requested nonsensical USBDEVFS_URB_SHORT_NOT_OK. vhci_hcd: default hub control req: 0000 v0000 i0000 l5 netlink: 2212 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 2212 bytes leftover after parsing attributes in process `syz-executor.0'. xt_HMARK: hash modulus can't be zero xt_HMARK: hash modulus can't be zero syz-executor.4 (9651) used greatest stack depth: 22808 bytes left netlink: 2212 bytes leftover after parsing attributes in process `syz-executor.0'. xt_HMARK: hash modulus can't be zero xt_HMARK: hash modulus can't be zero xt_HMARK: hash modulus can't be zero FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 1 CPU: 1 PID: 9736 Comm: syz-executor.1 Not tainted 4.14.166-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+0x142/0x197 lib/dump_stack.c:58 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0x10f/0x159 lib/fault-inject.c:149 should_failslab+0xdb/0x130 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3376 [inline] kmem_cache_alloc_trace+0x2e9/0x790 mm/slab.c:3616 kmalloc include/linux/slab.h:488 [inline] kzalloc include/linux/slab.h:661 [inline] kvm_uevent_notify_change.part.0+0x34c/0x440 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3977 kvm_uevent_notify_change arch/x86/kvm/../../../virt/kvm/kvm_main.c:3963 [inline] kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:763 [inline] kvm_put_kvm+0x9c/0xaa0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:806 kvm_vm_release+0x44/0x60 arch/x86/kvm/../../../virt/kvm/kvm_main.c:817 __fput+0x275/0x7a0 fs/file_table.c:210 ____fput+0x16/0x20 fs/file_table.c:244 task_work_run+0x114/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1da/0x220 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45b349 RSP: 002b:00007fd27ab5ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000021 RAX: 0000000000000005 RBX: 00007fd27ab5f6d4 RCX: 000000000045b349 RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006 R13: 0000000000000097 R14: 00000000004c1dc5 R15: 0000000000000000 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 0 PID: 9757 Comm: syz-executor.1 Not tainted 4.14.166-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+0x142/0x197 lib/dump_stack.c:58 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0x10f/0x159 lib/fault-inject.c:149 should_failslab+0xdb/0x130 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3376 [inline] kmem_cache_alloc_trace+0x2e9/0x790 mm/slab.c:3616 kmalloc include/linux/slab.h:488 [inline] kvm_uevent_notify_change.part.0+0x1e3/0x440 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3993 kvm_uevent_notify_change arch/x86/kvm/../../../virt/kvm/kvm_main.c:3963 [inline] kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:763 [inline] kvm_put_kvm+0x9c/0xaa0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:806 kvm_vm_release+0x44/0x60 arch/x86/kvm/../../../virt/kvm/kvm_main.c:817 __fput+0x275/0x7a0 fs/file_table.c:210 ____fput+0x16/0x20 fs/file_table.c:244 task_work_run+0x114/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1da/0x220 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45b349 RSP: 002b:00007fd27ab5ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000021 RAX: 0000000000000005 RBX: 00007fd27ab5f6d4 RCX: 000000000045b349 RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006 R13: 0000000000000097 R14: 00000000004c1dc5 R15: 0000000000000001 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 1 PID: 9810 Comm: syz-executor.1 Not tainted 4.14.166-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+0x142/0x197 lib/dump_stack.c:58 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0x10f/0x159 lib/fault-inject.c:149 should_failslab+0xdb/0x130 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3376 [inline] kmem_cache_alloc_trace+0x2e9/0x790 mm/slab.c:3616 kmalloc include/linux/slab.h:488 [inline] kzalloc include/linux/slab.h:661 [inline] kobject_uevent_env+0x208/0xc80 lib/kobject_uevent.c:397 kvm_uevent_notify_change.part.0+0x2d2/0x440 arch/x86/kvm/../../../virt/kvm/kvm_main.c:4004 kvm_uevent_notify_change arch/x86/kvm/../../../virt/kvm/kvm_main.c:3963 [inline] kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:763 [inline] kvm_put_kvm+0x9c/0xaa0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:806 kvm_vm_release+0x44/0x60 arch/x86/kvm/../../../virt/kvm/kvm_main.c:817 __fput+0x275/0x7a0 fs/file_table.c:210 ____fput+0x16/0x20 fs/file_table.c:244 task_work_run+0x114/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1da/0x220 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45b349 RSP: 002b:00007fd27ab5ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000021 RAX: 0000000000000005 RBX: 00007fd27ab5f6d4 RCX: 000000000045b349 RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006 R13: 0000000000000097 R14: 00000000004c1dc5 R15: 0000000000000002 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 1 PID: 9834 Comm: syz-executor.1 Not tainted 4.14.166-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+0x142/0x197 lib/dump_stack.c:58 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0x10f/0x159 lib/fault-inject.c:149 should_failslab+0xdb/0x130 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3376 [inline] __do_kmalloc mm/slab.c:3718 [inline] __kmalloc+0x2f0/0x7a0 mm/slab.c:3729 kmalloc include/linux/slab.h:493 [inline] kzalloc include/linux/slab.h:661 [inline] kobject_get_path+0xba/0x190 lib/kobject.c:154 kobject_uevent_env+0x22c/0xc80 lib/kobject_uevent.c:402 kvm_uevent_notify_change.part.0+0x2d2/0x440 arch/x86/kvm/../../../virt/kvm/kvm_main.c:4004 kvm_uevent_notify_change arch/x86/kvm/../../../virt/kvm/kvm_main.c:3963 [inline] kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:763 [inline] kvm_put_kvm+0x9c/0xaa0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:806 kvm_vm_release+0x44/0x60 arch/x86/kvm/../../../virt/kvm/kvm_main.c:817 __fput+0x275/0x7a0 fs/file_table.c:210 ____fput+0x16/0x20 fs/file_table.c:244 task_work_run+0x114/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1da/0x220 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45b349 RSP: 002b:00007fd27ab5ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000021