====================================================== WARNING: possible circular locking dependency detected 4.14.0+ #191 Not tainted ------------------------------------------------------ syz-executor0/11416 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] fast_dput fs/dcache.c:687 [inline] dput.part.23+0x492/0x830 fs/dcache.c:794 -> #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-executor0/11416: #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: 0 PID: 11416 Comm: syz-executor0 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:00007fea749acbe8 EFLAGS: 00000212 ORIG_RAX: 0000000000000113 RAX: ffffffffffffffda RBX: 0000000000758020 RCX: 0000000000452879 RDX: 0000000000000015 RSI: 0000000000000000 RDI: 0000000000000016 RBP: 0000000000000086 R08: 0000000000000006 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f2c80 R13: 00000000ffffffff R14: 00007fea749ad6d4 R15: 0000000000000000 SELinux: unrecognized netlink message: protocol=4 nlmsg_type=0 sclass=netlink_tcpdiag_socket pig=11440 comm=syz-executor2 SELinux: unrecognized netlink message: protocol=4 nlmsg_type=0 sclass=netlink_tcpdiag_socket pig=11440 comm=syz-executor2 could not allocate digest TFM handle @ނMZBڛxQ\: 29¾:r could not allocate digest TFM handle @ނMZBڛxQ\: 29¾:r : renamed from sit0 device  entered promiscuous mode device gre0 entered promiscuous mode ALSA: seq fatal error: cannot create timer (-19) netlink: 15 bytes leftover after parsing attributes in process `syz-executor1'. ALSA: seq fatal error: cannot create timer (-19) netlink: 8 bytes leftover after parsing attributes in process `syz-executor1'. netlink: 15 bytes leftover after parsing attributes in process `syz-executor1'. tmpfs: No value for mount option 'p:.t! ' sock: process `syz-executor4' is using obsolete setsockopt SO_BSDCOMPAT kvm: emulating exchange as write device gre0 entered promiscuous mode audit: type=1326 audit(1511500646.937:945): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=11861 comm="syz-executor5" exe="/root/syz-executor5" sig=31 arch=c000003e syscall=202 compat=0 ip=0x452879 code=0xffff0000 audit: type=1326 audit(1511500646.960:946): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=11858 comm="syz-executor0" exe="/root/syz-executor0" sig=31 arch=c000003e syscall=202 compat=0 ip=0x452879 code=0xffff0000 rpcbind: RPC call returned error 22 rpcbind: RPC call returned error 22 audit: type=1326 audit(1511500647.067:947): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=11861 comm="syz-executor5" exe="/root/syz-executor5" sig=31 arch=c000003e syscall=202 compat=0 ip=0x452879 code=0xffff0000 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=11888 comm=syz-executor7 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 device gre0 entered promiscuous mode nla_parse: 10 callbacks suppressed netlink: 8 bytes leftover after parsing attributes in process `syz-executor2'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor2'. netlink: 3 bytes leftover after parsing attributes in process `syz-executor2'. netlink: 3 bytes leftover after parsing attributes in process `syz-executor2'. device gre0 entered promiscuous mode QAT: Invalid ioctl device gre0 entered promiscuous mode netlink: 5 bytes leftover after parsing attributes in process `syz-executor5'. netlink: 5 bytes leftover after parsing attributes in process `syz-executor5'. QAT: Invalid ioctl device gre0 entered promiscuous mode netlink: 8 bytes leftover after parsing attributes in process `syz-executor3'. netlink: 21 bytes leftover after parsing attributes in process `syz-executor0'. netlink: 21 bytes leftover after parsing attributes in process `syz-executor0'. netlink: 8 bytes leftover after parsing attributes in process `syz-executor3'. audit: type=1326 audit(1511500648.931:948): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=12218 comm="syz-executor2" exe="/root/syz-executor2" sig=31 arch=c000003e syscall=202 compat=0 ip=0x452879 code=0xffff0000 device lo entered promiscuous mode audit: type=1326 audit(1511500649.029:949): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=12218 comm="syz-executor2" exe="/root/syz-executor2" sig=31 arch=c000003e syscall=202 compat=0 ip=0x452879 code=0xffff0000 sg_write: data in/out 1857891000/198 bytes for SCSI command 0x59-- guessing data in; program syz-executor7 not setting count and/or reply_len properly device gre0 entered promiscuous mode QAT: Invalid ioctl device gre0 entered promiscuous mode QAT: Invalid ioctl device gre0 entered promiscuous mode QAT: Invalid ioctl QAT: Invalid ioctl do_dccp_getsockopt: sockopt(PACKET_SIZE) is deprecated: fix your app do_dccp_getsockopt: sockopt(PACKET_SIZE) is deprecated: fix your app FAULT_FLAG_ALLOW_RETRY missing 30 CPU: 1 PID: 13001 Comm: syz-executor1 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 handle_userfault+0x12fa/0x24c0 fs/userfaultfd.c:427 do_anonymous_page mm/memory.c:3121 [inline] handle_pte_fault mm/memory.c:3934 [inline] __handle_mm_fault+0x2e8c/0x3ad0 mm/memory.c:4060 handle_mm_fault+0x334/0x8d0 mm/memory.c:4097 __do_page_fault+0x5c9/0xc90 arch/x86/mm/fault.c:1429 do_page_fault+0xee/0x720 arch/x86/mm/fault.c:1504 page_fault+0x22/0x30 arch/x86/entry/entry_64.S:1088 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:ffff8801d47af928 EFLAGS: 00010246 RAX: 0000000000010000 RBX: 0000000020011fd2 RCX: ffffffff82505471 RDX: 00000000000000c0 RSI: ffffc90001fce000 RDI: ffff8801d47afd28 RBP: ffff8801d47afa08 R08: 1ffff10038aef92a R09: 1ffff1003a8f5f1a R10: ffff8801ca3144c0 R11: 0000000000000000 R12: 1ffff1003a8f5f28 R13: ffff8801d47af9e0 R14: 0000000000000000 R15: ffff8801d47afd20 generic_perform_write+0x200/0x600 mm/filemap.c:3129 __generic_file_write_iter+0x366/0x5b0 mm/filemap.c:3264 generic_file_write_iter+0x399/0x7a0 mm/filemap.c:3292 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:00007f007e964be8 EFLAGS: 00000212 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000758020 RCX: 0000000000452879 RDX: 000000000000001c RSI: 0000000020011fd2 RDI: 0000000000000014 RBP: 000000000000038f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f2608 R13: 00000000ffffffff R14: 00007f007e9656d4 R15: 0000000000000000 nla_parse: 12 callbacks suppressed netlink: 64 bytes leftover after parsing attributes in process `syz-executor1'. tmpfs: No value for mount option 'o' netlink: 64 bytes leftover after parsing attributes in process `syz-executor1'. tmpfs: No value for mount option 'o' *** Guest State *** CR0: actual=0x0000000080000031, shadow=0x0000000060000011, gh_mask=fffffffffffffff7 CR4: actual=0x0000000000002050, shadow=0x0000000000000000, gh_mask=ffffffffffffe871 CR3 = 0x00000000fffbc000 RSP = 0x0000000000000004 RIP = 0x0000000000002000 RFLAGS=0x00080000 DR7 = 0x0000000000000400 Sysenter RSP=0000000000000f80 CS:RIP=0030:0000000000002810 CS: sel=0x0030, attr=0x0409b, limit=0x000fffff, base=0x0000000000000000 DS: sel=0x0038, attr=0x04093, limit=0x000fffff, base=0x0000000000000000 SS: sel=0x0038, attr=0x04093, limit=0x000fffff, base=0x0000000000000000 ES: sel=0x0038, attr=0x04093, limit=0x000fffff, base=0x0000000000000000 FS: sel=0x0038, attr=0x04093, limit=0x000fffff, base=0x0000000000000000 GS: sel=0x0038, attr=0x04093, limit=0x000fffff, base=0x0000000000000000 GDTR: limit=0x000007ff, base=0x0000000000001000 LDTR: sel=0x0008, attr=0x04082, limit=0x000007ff, base=0x0000000000001800 IDTR: limit=0x000001ff, base=0x0000000000003800 TR: sel=0x0000, attr=0x0008b, limit=0x0000ffff, base=0x0000000000000000 EFER = 0x0000000000000001 PAT = 0x0007040600070406 DebugCtl = 0x0000000000000000 DebugExceptions = 0x0000000000000000 Interruptibility = 00000000 ActivityState = 00000000 *** Host State *** RIP = 0xffffffff811bca33 RSP = 0xffff8801c69474c8 CS=0010 SS=0018 DS=0000 ES=0000 FS=0000 GS=0000 TR=0040 FSBase=00007f7637fdd700 GSBase=ffff8801db400000 TRBase=ffff8801db523140 GDTBase=ffffffffff576000 IDTBase=ffffffffff57b000 CR0=0000000080050033 CR3=00000001c0646000 CR4=00000000001426f0 Sysenter RSP=0000000000000000 CS:RIP=0010:ffffffff8513c0b0 EFER = 0x0000000000000d01 PAT = 0x0000000000000000 *** Control State *** PinBased=0000003f CPUBased=b6a1edfa SecondaryExec=0000004b EntryControls=0000d1ff ExitControls=0023efff ExceptionBitmap=00060042 PFECmask=00000000 PFECmatch=00000000 VMEntry: intr_info=00000000 errcode=00000000 ilen=00000000 VMExit: intr_info=00000000 errcode=00000000 ilen=00000000 reason=80000021 qualification=0000000000000000 IDTVectoring: info=00000000 errcode=00000000 TSC Offset = 0xffffffca53b37369 TPR Threshold = 0x00 EPT pointer = 0x00000001d8efc01e netlink: 1 bytes leftover after parsing attributes in process `syz-executor2'. netlink: 1 bytes leftover after parsing attributes in process `syz-executor2'.