============================================ WARNING: possible recursive locking detected 4.15.0-rc8+ #269 Not tainted -------------------------------------------- syz-executor1/7710 is trying to acquire lock: (&vq->mutex){+.+.}, at: [<00000000bc3b5be9>] vhost_dev_lock_vqs drivers/vhost/vhost.c:907 [inline] (&vq->mutex){+.+.}, at: [<00000000bc3b5be9>] vhost_process_iotlb_msg drivers/vhost/vhost.c:997 [inline] (&vq->mutex){+.+.}, at: [<00000000bc3b5be9>] vhost_chr_write_iter+0x278/0x1580 drivers/vhost/vhost.c:1046 but task is already holding lock: (&vq->mutex){+.+.}, at: [<00000000bc3b5be9>] vhost_dev_lock_vqs drivers/vhost/vhost.c:907 [inline] (&vq->mutex){+.+.}, at: [<00000000bc3b5be9>] vhost_process_iotlb_msg drivers/vhost/vhost.c:997 [inline] (&vq->mutex){+.+.}, at: [<00000000bc3b5be9>] vhost_chr_write_iter+0x278/0x1580 drivers/vhost/vhost.c:1046 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&vq->mutex); lock(&vq->mutex); *** DEADLOCK *** May be due to missing lock nesting notation 1 lock held by syz-executor1/7710: #0: (&vq->mutex){+.+.}, at: [<00000000bc3b5be9>] vhost_dev_lock_vqs drivers/vhost/vhost.c:907 [inline] #0: (&vq->mutex){+.+.}, at: [<00000000bc3b5be9>] vhost_process_iotlb_msg drivers/vhost/vhost.c:997 [inline] #0: (&vq->mutex){+.+.}, at: [<00000000bc3b5be9>] vhost_chr_write_iter+0x278/0x1580 drivers/vhost/vhost.c:1046 stack backtrace: CPU: 0 PID: 7710 Comm: syz-executor1 Not tainted 4.15.0-rc8+ #269 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_deadlock_bug kernel/locking/lockdep.c:1756 [inline] check_deadlock kernel/locking/lockdep.c:1800 [inline] validate_chain kernel/locking/lockdep.c:2396 [inline] __lock_acquire+0xe8f/0x3e00 kernel/locking/lockdep.c:3426 lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3914 __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 vhost_dev_lock_vqs drivers/vhost/vhost.c:907 [inline] vhost_process_iotlb_msg drivers/vhost/vhost.c:997 [inline] vhost_chr_write_iter+0x278/0x1580 drivers/vhost/vhost.c:1046 vhost_net_chr_write_iter+0x59/0x70 drivers/vhost/net.c:1353 call_write_iter include/linux/fs.h:1772 [inline] new_sync_write fs/read_write.c:469 [inline] __vfs_write+0x684/0x970 fs/read_write.c:482 vfs_write+0x189/0x510 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+0x29/0xa0 RIP: 0033:0x452ee9 RSP: 002b:00007f9419061c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000452ee9 RDX: 0000000000000068 RSI: 00000000202ff000 RDI: 0000000000000013 RBP: 0000000000000327 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f3c48 R13: 00000000ffffffff R14: 00007f94190626d4 R15: 0000000000000000 binder: 7728:7731 Acquire 1 refcount change on invalid ref 0 ret -22 binder: 7728:7731 unknown command 0 binder: 7728:7731 ioctl c0306201 2000a000 returned -22 binder_alloc: binder_alloc_mmap_handler: 7728 20000000-20002000 already mapped failed -16 sctp: [Deprecated]: syz-executor1 (pid 7774) Use of int in maxseg socket option. Use struct sctp_assoc_value instead sctp: [Deprecated]: syz-executor1 (pid 7774) Use of int in maxseg socket option. Use struct sctp_assoc_value instead QAT: Invalid ioctl QAT: Invalid ioctl TCP: request_sock_TCPv6: Possible SYN flooding on port 20010. Sending cookies. Check SNMP counters. binder_alloc: binder_alloc_mmap_handler: 8134 20000000-20002000 already mapped failed -16 binder: 8134:8136 ioctl 8906 20008ffc returned -22 sock: sock_set_timeout: `syz-executor6' (pid 8155) tries to set negative timeout binder: 8134:8151 ioctl c0045516 20009ffc returned -22 binder: 8134:8144 ioctl 890b 20001000 returned -22 binder: 8134:8144 ioctl c4c85513 20001000 returned -22 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=256 sclass=netlink_route_socket pig=8166 comm=syz-executor0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=256 sclass=netlink_route_socket pig=8169 comm=syz-executor0 sock: sock_set_timeout: `syz-executor6' (pid 8170) tries to set negative timeout DRBG: could not allocate digest TFM handle: hmac(sha512) DRBG: could not allocate digest TFM handle: hmac(sha512) handle_userfault: 85 callbacks suppressed FAULT_FLAG_ALLOW_RETRY missing 30 CPU: 1 PID: 8452 Comm: syz-executor7 Not tainted 4.15.0-rc8+ #269 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 handle_userfault+0x12fa/0x24c0 fs/userfaultfd.c:427 do_anonymous_page mm/memory.c:3127 [inline] handle_pte_fault mm/memory.c:3941 [inline] __handle_mm_fault+0x32a3/0x3ce0 mm/memory.c:4067 handle_mm_fault+0x334/0x8d0 mm/memory.c:4104 __do_page_fault+0x5c9/0xc90 arch/x86/mm/fault.c:1430 do_page_fault+0xee/0x720 arch/x86/mm/fault.c:1505 page_fault+0x2c/0x60 arch/x86/entry/entry_64.S:1260 RIP: 0010:fault_in_pages_readable include/linux/pagemap.h:601 [inline] RIP: 0010:iov_iter_fault_in_readable+0x1a7/0x410 lib/iov_iter.c:421 RSP: 0018:ffff8801bd097928 EFLAGS: 00010246 RAX: 0000000000010000 RBX: 0000000020011fd2 RCX: ffffffff82587fc1 RDX: 00000000000000ff RSI: ffffc90002ccf000 RDI: ffff8801bd097d28 RBP: ffff8801bd097a08 R08: 0000000000000000 R09: 1ffff10037a12ee7 R10: ffff8801bd097858 R11: ffff8801bd4cec00 R12: 1ffff10037a12f28 R13: ffff8801bd0979e0 R14: 0000000000000000 R15: ffff8801bd097d20 generic_perform_write+0x200/0x600 mm/filemap.c:3129 __generic_file_write_iter+0x366/0x5b0 mm/filemap.c:3264 generic_file_write_iter+0x399/0x790 mm/filemap.c:3292 call_write_iter include/linux/fs.h:1772 [inline] new_sync_write fs/read_write.c:469 [inline] __vfs_write+0x684/0x970 fs/read_write.c:482 vfs_write+0x189/0x510 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+0x29/0xa0 RIP: 0033:0x452ee9 RSP: 002b:00007f6689786c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000452ee9 RDX: 0000000000000030 RSI: 0000000020011fd2 RDI: 0000000000000014 RBP: 0000000000000069 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006efa78 R13: 00000000ffffffff R14: 00007f66897876d4 R15: 0000000000000000 audit: type=1326 audit(1516425776.029:352): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=8526 comm="syz-executor1" exe="/root/syz-executor1" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452ee9 code=0x7ffc0000 audit: type=1326 audit(1516425776.054:353): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=8526 comm="syz-executor1" exe="/root/syz-executor1" sig=0 arch=c000003e syscall=222 compat=0 ip=0x452ee9 code=0x7ffc0000 audit: type=1326 audit(1516425776.064:354): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=8526 comm="syz-executor1" exe="/root/syz-executor1" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452ee9 code=0x7ffc0000 audit: type=1326 audit(1516425776.066:355): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=8526 comm="syz-executor1" exe="/root/syz-executor1" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452ee9 code=0x7ffc0000 audit: type=1326 audit(1516425776.069:356): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=8526 comm="syz-executor1" exe="/root/syz-executor1" sig=0 arch=c000003e syscall=317 compat=0 ip=0x452ee9 code=0x7ffc0000 audit: type=1326 audit(1516425776.069:357): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=8526 comm="syz-executor1" exe="/root/syz-executor1" sig=31 arch=c000003e syscall=202 compat=0 ip=0x452ee9 code=0x0 audit: type=1326 audit(1516425776.238:358): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=8526 comm="syz-executor1" exe="/root/syz-executor1" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452ee9 code=0x7ffc0000 audit: type=1326 audit(1516425776.238:359): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=8526 comm="syz-executor1" exe="/root/syz-executor1" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452ee9 code=0x7ffc0000 audit: type=1326 audit(1516425776.264:360): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=8526 comm="syz-executor1" exe="/root/syz-executor1" sig=0 arch=c000003e syscall=317 compat=0 ip=0x452ee9 code=0x7ffc0000 netlink: 3 bytes leftover after parsing attributes in process `syz-executor6'. netlink: 3 bytes leftover after parsing attributes in process `syz-executor6'. binder: 8586:8592 Acquire 1 refcount change on invalid ref 0 ret -22 binder: 8586:8592 Release 1 refcount change on invalid ref 0 ret -22 binder: 8586:8608 Acquire 1 refcount change on invalid ref 0 ret -22 binder: 8586:8608 Release 1 refcount change on invalid ref 0 ret -22 IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready kvm [8973]: vcpu0, guest rIP: 0xfff0 Hyper-V uhandled wrmsr: 0x40000020 data 0x0 binder: BINDER_SET_CONTEXT_MGR already set binder: 9026:9033 ioctl 40046207 0 returned -16 rfkill: input handler disabled rfkill: input handler enabled binder: 9203:9205 transaction failed 29189/-22, size 0-0 line 2788 binder: 9203:9221 unknown command 0 binder: 9203:9221 ioctl c0306201 20007000 returned -22 kauditd_printk_skb: 20 callbacks suppressed audit: type=1326 audit(1516425780.401:381): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=9513 comm="syz-executor3" exe="/root/syz-executor3" sig=9 arch=c000003e syscall=202 compat=0 ip=0x452ee9 code=0x0 audit: type=1326 audit(1516425780.492:382): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=9513 comm="syz-executor3" exe="/root/syz-executor3" sig=9 arch=c000003e syscall=202 compat=0 ip=0x452ee9 code=0x0 sit: non-ECT from 172.20.6.0 with TOS=0x3 sit: non-ECT from 172.20.6.0 with TOS=0x3 l2tp_ppp: tunl 59: set debug=f55d40e audit: type=1400 audit(1516425780.957:383): avc: denied { create } for pid=9646 comm="syz-executor5" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_scsitransport_socket permissive=1 audit: type=1400 audit(1516425781.466:384): avc: denied { setfcap } for pid=9803 comm="syz-executor4" capability=31 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 1 CPU: 0 PID: 9893 Comm: syz-executor2 Not tainted 4.15.0-rc8+ #269 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:3289 [inline] kmem_cache_alloc_node_trace+0x5a/0x750 mm/slab.c:3651 __do_kmalloc_node mm/slab.c:3671 [inline] __kmalloc_node+0x33/0x70 mm/slab.c:3679 kmalloc_node include/linux/slab.h:541 [inline] kvmalloc_node+0x99/0xd0 mm/util.c:397 kvmalloc include/linux/mm.h:541 [inline] kvzalloc include/linux/mm.h:549 [inline] alloc_netdev_mqs+0x16d/0xed0 net/core/dev.c:8123 ppp_create_interface drivers/net/ppp/ppp_generic.c:3018 [inline] ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:866 [inline] ppp_ioctl+0x1715/0x2a50 drivers/net/ppp/ppp_generic.c:602 vfs_ioctl fs/ioctl.c:46 [inline] do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 entry_SYSCALL_64_fastpath+0x29/0xa0 RIP: 0033:0x452ee9 RSP: 002b:00007f83f8262c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f83f8262aa0 RCX: 0000000000452ee9 RDX: 0000000020ee5000 RSI: 00000000c004743e RDI: 0000000000000014 RBP: 00007f83f8262a90 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000004b7c76 R13: 00007f83f8262bc8 R14: 00000000004b7c76 R15: 0000000000000000