witness: lock order reversal: 1st 0xffffffff8290fe50 netlock (netlock) 2nd 0xfffffd8073690760 vmmaplk (&map->lock) lock order "&map->lock"(rwlock) -> "netlock"(rwlock) first seen at: #0 rw_enter_write+0x5b sys/kern/kern_rwlock.c:128 #1 udp_sysctl+0x8a sys/netinet/udp_usrreq.c:1269 #2 sys_sysctl+0x209 sys/kern/kern_sysctl.c:249 #3 syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline] #3 syscall+0x489 sys/arch/amd64/amd64/trap.c:585 #4 Xsyscall+0x128 lock order "netlock"(rwlock) -> "&map->lock"(rwlock) first seen at: #0 rw_enter_read+0x66 sys/kern/kern_rwlock.c:112 #1 uvmfault_lookup+0xd9 sys/uvm/uvm_fault.c:1758 #2 uvm_fault_check+0x3a sys/uvm/uvm_fault.c:674 #3 uvm_fault+0x102 sys/uvm/uvm_fault.c:602 #4 kpageflttrap+0x209 #5 kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 #6 alltraps_kern_meltdown+0x7b #7 copyout+0x53 #8 ifioctl_get+0x2dd #9 soo_ioctl+0x26c #10 sys_ioctl+0x4a2 #11 syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline] #11 syscall+0x489 sys/arch/amd64/amd64/trap.c:585 #12 Xsyscall+0x128 Stopped at db_enter+0x18: addq $0x8,%rsp ddb{0}> ddb{0}> set $lines = 0 ddb{0}> set $maxwidth = 0 ddb{0}> show panic the kernel did not panic ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 witness_checkorder(fffffd8073690760,1,0) at witness_checkorder+0x10b7 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd8073690760,1,0) at witness_checkorder+0x10b7 sys/kern/subr_witness.c:1105 rw_enter_read(fffffd8073690750) at rw_enter_read+0x66 sys/kern/kern_rwlock.c:112 uvmfault_lookup(ffff80002e37ed30,0) at uvmfault_lookup+0xd9 sys/uvm/uvm_fault.c:1758 uvm_fault_check(ffff80002e37ed30,ffff80002e37ed68,ffff80002e37ed90) at uvm_fault_check+0x3a sys/uvm/uvm_fault.c:674 uvm_fault(fffffd8073690748,20000000,0,2) at uvm_fault+0x102 sys/uvm/uvm_fault.c:602 kpageflttrap(ffff80002e37eec0,20000300) at kpageflttrap+0x209 kerntrap(ffff80002e37eec0) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b copyout() at copyout+0x53 ifioctl_get(c0106924,ffff80002e37f170) at ifioctl_get+0x2dd soo_ioctl(fffffd807360aad0,c0106924,ffff80002e37f170,ffff800021262a90) at soo_ioctl+0x26c sys_ioctl(ffff800021262a90,ffff80002e37f288,ffff80002e37f2e0) at sys_ioctl+0x4a2 syscall(ffff80002e37f350) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff80002e37f350) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x8b905d5e780, count: -15 ddb{0}> show registers rdi 0x3 rsi 0xffffffff8294abb0 __sancov_gen_cov_switch_values.134 rbp 0xffff80002e37ea20 rbx 0x3 rdx 0 rcx 0 rax 0xffff800021262a90 r8 0xffff80002e37e990 r9 0x8080808080808080 r10 0x99e1f2930c037094 r11 0xd9a3b2990d240b02 r12 0xffffffff82ab06f0 w_lodata+0x52d80 r13 0 r14 0xffffffff82aa59b0 w_lodata+0x48040 r15 0xfffffd8002f62d80 rip 0xffffffff8138d658 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff80002e37ea10 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor.2) pid=439217 stat=onproc flags process=10 proc=4000000 pri=32, usrpri=80, nice=20 forw=0xffffffffffffffff, list=0xffff8000ffff67f0,0xffff800021262560 process=0xffff80002a1314e8 user=0xffff80002e37a000, vmspace=0xfffffd8073690748 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 63968 172878 18949 32767 2 0x10 syz-executor.1 21384 286906 7356 32767 2 0x10 syz-executor.6 21384 169975 7356 32767 3 0x4000090 fsleep syz-executor.6 13565 155119 33995 32767 2 0x10 syz-executor.2 *13565 439217 33995 32767 7 0x4000010 syz-executor.2 26322 358317 85260 32767 2 0x10 syz-executor.3 26322 74928 85260 32767 3 0x4000090 netio syz-executor.3 76572 309410 76782 32767 3 0x90 nanoslp syz-executor.7 76782 174817 17831 0 3 0x82 wait syz-executor.7 68100 109927 0 0 3 0x14200 bored sosplice 7356 510982 25339 32767 3 0x90 nanoslp syz-executor.6 51574 187195 89364 32767 2 0x10 syz-executor.0 25339 275549 17831 0 3 0x82 wait syz-executor.6 58400 24104 77412 32767 7 0x10 syz-executor.5 85260 452824 98201 32767 3 0x90 nanoslp syz-executor.3 10091 227607 15376 32767 2 0x10 syz-executor.4 77412 35891 17831 0 3 0x82 wait syz-executor.5 98201 456806 17831 0 3 0x82 wait syz-executor.3 15376 468277 17831 0 3 0x82 wait syz-executor.4 18949 243870 37611 32767 3 0x90 nanoslp syz-executor.1 33995 381468 63816 32767 3 0x90 nanoslp syz-executor.2 89364 63590 17831 0 3 0x82 wait syz-executor.0 63816 44733 17831 0 3 0x82 wait syz-executor.2 37611 105951 17831 0 3 0x82 wait syz-executor.1 17831 476120 75503 0 3 0x82 thrsleep syz-fuzzer 17831 172980 75503 0 3 0x4000082 nanoslp syz-fuzzer 17831 53872 75503 0 3 0x4000082 kqread syz-fuzzer 17831 40856 75503 0 3 0x4000082 thrsleep syz-fuzzer 17831 305591 75503 0 3 0x4000082 thrsleep syz-fuzzer 17831 173326 75503 0 3 0x4000082 thrsleep syz-fuzzer 17831 374750 75503 0 3 0x4000082 thrsleep syz-fuzzer 17831 517614 75503 0 3 0x4000082 thrsleep syz-fuzzer 17831 383282 75503 0 3 0x4000082 thrsleep syz-fuzzer 75503 421352 60735 0 3 0x10008a sigsusp ksh 60735 252735 420 0 3 0x9a kqread sshd 97598 368851 1 0 3 0x100083 ttyin getty 420 508412 1 0 3 0x88 kqread sshd 13253 107590 73959 73 3 0x1100090 kqread syslogd 73959 244479 1 0 3 0x100082 netio syslogd 82492 249395 1 0 3 0x100080 kqread resolvd 27650 233627 90340 77 3 0x100092 kqread dhcpleased 70485 243783 90340 77 3 0x100092 kqread dhcpleased 90340 515234 1 0 3 0x80 kqread dhcpleased 19046 501668 0 0 3 0x14200 bored smr 44220 171597 0 0 2 0x14200 zerothread 51502 44351 0 0 3 0x14200 aiodoned aiodoned 34687 381574 0 0 3 0x14200 syncer update 75095 285519 0 0 3 0x14200 cleaner cleaner 24305 518970 0 0 3 0x14200 reaper reaper 47477 384954 0 0 3 0x14200 pgdaemon pagedaemon 28864 443454 0 0 3 0x14200 bored viomb 79603 3227 0 0 3 0x40014200 acpi0 acpi0 98045 246852 0 0 3 0x40014200 idle1 24869 510658 0 0 3 0x14200 bored softnet 22338 64520 0 0 3 0x14200 bored systqmp 34264 154721 0 0 3 0x14200 bored systq 86687 491878 0 0 3 0x40014200 bored softclock 69932 66790 0 0 3 0x40014200 idle0 1 452652 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 13565 (syz-executor.2) thread 0xffff800021262a90 (439217) shared rwlock netlock r = 0 (0xffffffff8290fe50) #0 witness_lock+0x44d #1 ifioctl_get+0x2d5 sys/net/if.c:2319 #2 soo_ioctl+0x26c #3 sys_ioctl+0x4a2 #4 syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline] #4 syscall+0x489 sys/arch/amd64/amd64/trap.c:585 #5 Xsyscall+0x128 exclusive kernel_lock &kernel_lock r = 0 (0xffffffff829de988) #0 witness_lock+0x44d #1 soo_ioctl+0x25a sys/kern/sys_socket.c:136 #2 sys_ioctl+0x4a2 #3 syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline] #3 syscall+0x489 sys/arch/amd64/amd64/trap.c:585 #4 Xsyscall+0x128 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10175 6407K 6419K 78643K 11271 0 pcb 13 12K 14K 78643K 17 0 rtable 252 7K 7K 78643K 502 0 ifaddr 81 16K 16K 78643K 96 0 sysctl 2 0K 0K 78643K 2 0 counters 56 35K 35K 78643K 60 0 ioctlops 0 0K 2K 78643K 41 0 iov 0 0K 32K 78643K 1508 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1270 79K 79K 78643K 1732 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 19 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 0K 78643K 540 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 22 81K 121K 78643K 1724 0 sigio 0 0K 0K 78643K 2 0 proc 56 74K 123K 78643K 659 0 subproc 104 6K 6K 78643K 130 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 78 0 in_multi 99 6K 6K 78643K 136 0 ether_multi 1 0K 0K 78643K 5 0 mrt 1 0K 0K 78643K 1 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 67 307K 307K 78643K 67 0 exec 0 0K 2K 78643K 752 0 tdb 3 0K 0K 78643K 3 0 pagedep 1 8K 8K 78643K 1 0 inodedep 1 32K 32K 78643K 1 0 newblk 1 0K 0K 78643K 1 0 VM swap 7 26K 26K 78643K 7 0 UVM amap 316 84K 92K 78643K 23305 0 UVM aobj 52 3K 3K 78643K 55 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 36 0 NDP 11 0K 2K 78643K 33 0 temp 125 4707K 4771K 78643K 7649 0 kqueue 12 18K 26K 78643K 158 0 SYN cache 2 16K 16K 78643K 2 0 ddb{0}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle plcache 128 22 0 0 1 0 1 1 0 8 0 rtpcb 120 193 0 190 4 1 3 3 0 8 2 rtentry 112 143 0 26 4 0 4 4 0 8 0 unpcb 136 2650 0 2635 19 13 6 6 0 8 5 syncache 296 20 0 20 4 4 0 1 0 8 0 tcpqe 32 74 0 74 2 2 0 1 0 8 0 tcpcb 736 593 0 571 20 18 2 14 0 8 0 arp 120 22 0 4 1 0 1 1 0 8 0 ipq 40 3 0 2 2 1 1 1 0 8 0 ipqe 40 10 0 9 2 1 1 1 0 8 0 inpcb 304 1244 0 1233 31 25 6 12 0 8 5 rttmr 72 3 0 2 1 0 1 1 0 8 0 nd6 48 39 0 9 1 0 1 1 0 8 0 kcovpl 48 10 0 2 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 627 0 105 33 0 33 33 0 8 0 art_table 32 628 0 105 5 0 5 5 0 8 0 art_node 16 142 0 35 1 0 1 1 0 8 0 sysvmsgpl 40 2 0 0 1 0 1 1 0 8 0 semapl 112 538 0 528 1 0 1 1 0 8 0 shmpl 112 52 0 3 2 0 2 2 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 3706 0 2278 90 0 90 90 0 8 0 ffsino 272 3706 0 2278 96 0 96 96 0 8 0 nchpl 144 6195 0 4569 62 0 62 62 0 8 0 uvmvnodes 80 3845 0 0 79 0 79 79 0 8 0 vnodes 224 3845 0 0 227 0 227 227 0 8 0 namei 1024 19914 0 19914 3 2 1 2 0 8 1 percpumem 16 42 0 2 1 0 1 1 0 8 0 scxspl 216 21476 0 21476 14 11 3 8 0 8 3 plimitpl 152 234 0 212 1 0 1 1 0 8 0 sigapl 424 2003 0 1954 7 1 6 7 0 8 0 futexpl 64 12658 0 12657 3 2 1 1 0 8 0 knotepl 120 403 0 0 11 0 11 11 0 8 0 kqueuepl 216 572 0 564 9 6 3 3 0 8 2 pipepl 336 331 0 303 12 6 6 8 0 8 3 fdescpl 496 1988 0 1955 7 2 5 6 0 8 0 filepl 152 12078 0 11836 27 12 15 16 0 8 5 lockfpl 104 231 0 229 1 0 1 1 0 8 0 lockfspl 48 47 0 45 1 0 1 1 0 8 0 sessionpl 144 25 0 9 1 0 1 1 0 8 0 pgrppl 48 28 0 12 1 0 1 1 0 8 0 ucredpl 96 2095 0 2077 1 0 1 1 0 8 0 zombiepl 144 1955 0 1954 1 0 1 1 0 8 0 processpl 1064 2003 0 1954 5 1 4 4 0 8 0 procpl 672 5026 0 4966 9 2 7 8 0 8 1 sosppl 168 14 0 14 3 2 1 1 0 8 1 sockpl 480 4171 0 4142 111 100 11 21 0 8 7 mcl64k 65536 17 0 0 3 0 3 3 0 8 0 mcl16k 16384 17 0 0 3 0 3 3 0 8 0 mcl12k 12288 13 0 0 2 0 2 2 0 8 0 mcl9k 9216 6 0 0 1 0 1 1 0 8 0 mcl8k 8192 17 0 0 3 0 3 3 0 8 0 mcl4k 4096 17 0 0 3 0 3 3 0 8 0 mcl2k2 2112 6 0 0 1 0 1 1 0 8 0 mcl2k 2048 209 0 0 21 0 21 21 0 8 0 mtagpl 96 3 0 0 1 0 1 1 0 8 0 mbufpl 256 349 0 0 19 0 19 19 0 8 0 bufpl 288 6635 0 300 453 0 453 453 0 8 0 anonpl 24 518313 0 504877 140 29 111 113 0 186 17 amapchunkpl 152 56608 0 55891 50 14 36 43 0 158 4 amappl16 200 4130 0 3752 30 1 29 29 0 8 8 amappl15 192 439 0 433 1 0 1 1 0 8 0 amappl14 184 408 0 400 1 0 1 1 0 8 0 amappl13 176 532 0 528 1 0 1 1 0 8 0 amappl12 168 69 0 67 1 0 1 1 0 8 0 amappl11 160 57 0 46 1 0 1 1 0 8 0 amappl10 152 49 0 45 1 0 1 1 0 8 0 amappl9 144 655 0 652 1 0 1 1 0 8 0 amappl8 136 1052 0 976 3 0 3 3 0 8 0 amappl7 128 511 0 493 1 0 1 1 0 8 0 amappl6 120 401 0 378 2 1 1 2 0 8 0 amappl5 112 1645 0 1626 1 0 1 1 0 8 0 amappl4 104 1062 0 1035 2 1 1 2 0 8 0 amappl3 96 319 0 308 1 0 1 1 0 8 0 amappl2 88 1077 0 1035 3 1 2 3 0 8 0 amappl1 80 38635 0 38031 19 4 15 18 0 8 0 amappl 88 22792 0 22558 7 0 7 7 0 92 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma1024 1024 1 0 0 1 0 1 1 0 8 0 dma256 256 6 0 6 1 1 0 1 0 8 0 dma128 128 253 0 253 1 1 0 1 0 8 0 dma64 64 6 0 6 1 1 0 1 0 8 0 dma32 32 7 0 7 1 1 0 1 0 8 0 dma16 16 18 0 17 1 0 1 1 0 8 0 aobjpl 72 54 0 3 1 0 1 1 0 8 0 uaddrrnd 24 1988 0 1955 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1988 0 1955 1 0 1 1 0 8 0 vmmpekpl 168 19185 0 19134 3 0 3 3 0 8 0 vmmpepl 168 182491 0 180033 147 20 127 132 0 357 8 vmsppl 368 1987 0 1955 4 0 4 4 0 8 0 rwobjpl 56 48057 0 42866 76 2 74 74 0 8 0 pdppl 4096 3983 0 3910 152 71 81 93 0 8 8 pvpl 32 993246 0 974857 273 82 191 259 0 265 25 pmappl 248 1987 0 1955 4 1 3 3 0 8 0 extentpl 40 58 0 38 1 0 1 1 0 8 0 phpool 112 922 0 99 24 0 24 24 0 8 0 ddb{0}> machine ddbcpu 0 Invalid cpu 0 ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 witness_checkorder(fffffd8073690760,1,0) at witness_checkorder+0x10b7 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd8073690760,1,0) at witness_checkorder+0x10b7 sys/kern/subr_witness.c:1105 rw_enter_read(fffffd8073690750) at rw_enter_read+0x66 sys/kern/kern_rwlock.c:112 uvmfault_lookup(ffff80002e37ed30,0) at uvmfault_lookup+0xd9 sys/uvm/uvm_fault.c:1758 uvm_fault_check(ffff80002e37ed30,ffff80002e37ed68,ffff80002e37ed90) at uvm_fault_check+0x3a sys/uvm/uvm_fault.c:674 uvm_fault(fffffd8073690748,20000000,0,2) at uvm_fault+0x102 sys/uvm/uvm_fault.c:602 kpageflttrap(ffff80002e37eec0,20000300) at kpageflttrap+0x209 kerntrap(ffff80002e37eec0) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b copyout() at copyout+0x53 ifioctl_get(c0106924,ffff80002e37f170) at ifioctl_get+0x2dd soo_ioctl(fffffd807360aad0,c0106924,ffff80002e37f170,ffff800021262a90) at soo_ioctl+0x26c sys_ioctl(ffff800021262a90,ffff80002e37f288,ffff80002e37f2e0) at sys_ioctl+0x4a2 syscall(ffff80002e37f350) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff80002e37f350) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x8b905d5e780, count: -15 ddb{0}> machine ddbcpu 1 Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp ddb{1}> trace x86_ipi_db(ffff800020ce8ff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:393 x86_ipi_handler() at x86_ipi_handler+0xb7 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23 __mp_lock(ffffffff829de780) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff829de780) at __mp_lock+0x122 sys/kern/kern_lock.c:147 syscall(ffff80002a121530) at syscall+0x3ef mi_syscall sys/sys/syscall_mi.h:93 [inline] syscall(ffff80002a121530) at syscall+0x3ef sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffc0480, count: -6