witness: lock order reversal: 1st 0xffffffff8290fe50 netlock (netlock) 2nd 0xfffffd80771cf1a0 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(fffffd80771cf1a0,1,0) at witness_checkorder+0x10b7 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd80771cf1a0,1,0) at witness_checkorder+0x10b7 sys/kern/subr_witness.c:1105 rw_enter_read(fffffd80771cf190) at rw_enter_read+0x66 sys/kern/kern_rwlock.c:112 uvmfault_lookup(ffff80002e396960,0) at uvmfault_lookup+0xd9 sys/uvm/uvm_fault.c:1758 uvm_fault_check(ffff80002e396960,ffff80002e396998,ffff80002e3969c0) at uvm_fault_check+0x3a sys/uvm/uvm_fault.c:674 uvm_fault(fffffd80771cf188,20000000,0,2) at uvm_fault+0x102 sys/uvm/uvm_fault.c:602 kpageflttrap(ffff80002e396af0,20000300) at kpageflttrap+0x209 kerntrap(ffff80002e396af0) 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,ffff80002e396da0) at ifioctl_get+0x2dd soo_ioctl(fffffd80697bc148,c0106924,ffff80002e396da0,ffff80002cd66fd0) at soo_ioctl+0x26c sys_ioctl(ffff80002cd66fd0,ffff80002e396eb8,ffff80002e396f10) at sys_ioctl+0x4a2 syscall(ffff80002e396f80) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff80002e396f80) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xe89fb7a5d80, count: -15 ddb{0}> show registers rdi 0x3 rsi 0xffffffff8294abb0 __sancov_gen_cov_switch_values.134 rbp 0xffff80002e396650 rbx 0x3 rdx 0 rcx 0 rax 0xffff80002cd66fd0 r8 0xffff80002e3965c0 r9 0x8080808080808080 r10 0x182e32bd8c8e0c56 r11 0xe58d8870bfcf9c2c r12 0xffffffff82ab04e0 w_lodata+0x52b70 r13 0 r14 0xffffffff82aa98f0 w_lodata+0x4bf80 r15 0xfffffd8002f62d80 rip 0xffffffff8138d658 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff80002e396640 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor.2) pid=237978 stat=onproc flags process=10 proc=4000000 pri=32, usrpri=74, nice=20 forw=0xffffffffffffffff, list=0xffff8000ffff6010,0xffffffff82b3d400 process=0xffff80002992a9b0 user=0xffff80002e392000, vmspace=0xfffffd80771cf188 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 22400 181970 85280 32767 2 0x10 syz-executor.2 *22400 237978 85280 32767 7 0x4000010 syz-executor.2 4362 322477 44264 32767 3 0x90 nanoslp syz-executor.1 4362 81336 44264 32767 3 0x4000090 msgwait syz-executor.1 4362 80095 44264 32767 3 0x4000090 fsleep syz-executor.1 78833 196522 0 0 3 0x14200 bored sosplice 81338 149986 88740 32767 3 0x90 nanoslp syz-executor.6 92734 426058 71687 32767 3 0x90 nanoslp syz-executor.7 44793 181197 16593 32767 3 0x90 piperd syz-executor.5 88740 140695 72289 0 3 0x82 wait syz-executor.6 15470 446962 33993 32767 3 0x90 piperd syz-executor.4 71687 141711 72289 0 3 0x82 wait syz-executor.7 16593 9830 72289 0 3 0x82 wait syz-executor.5 33993 387824 72289 0 3 0x82 wait syz-executor.4 85280 21563 77100 32767 3 0x90 nanoslp syz-executor.2 29326 16610 75813 32767 3 0x90 piperd syz-executor.3 44264 475526 80934 32767 3 0x90 nanoslp syz-executor.1 77100 336162 72289 0 3 0x82 wait syz-executor.2 69071 26911 72673 32767 3 0x90 piperd syz-executor.0 75813 18278 72289 0 3 0x82 wait syz-executor.3 80934 4274 72289 0 3 0x82 wait syz-executor.1 72673 232627 72289 0 3 0x82 wait syz-executor.0 72289 327143 42209 0 3 0x82 thrsleep syz-fuzzer 72289 363074 42209 0 3 0x4000082 thrsleep syz-fuzzer 72289 99452 42209 0 3 0x4000082 thrsleep syz-fuzzer 72289 508656 42209 0 3 0x4000082 thrsleep syz-fuzzer 72289 383560 42209 0 3 0x4000082 kqread syz-fuzzer 72289 75305 42209 0 3 0x4000082 thrsleep syz-fuzzer 72289 145087 42209 0 3 0x4000082 thrsleep syz-fuzzer 72289 402259 42209 0 3 0x4000082 thrsleep syz-fuzzer 72289 196620 42209 0 3 0x4000082 thrsleep syz-fuzzer 42209 185575 69644 0 3 0x10008a sigsusp ksh 69644 433180 57824 0 3 0x9a kqread sshd 55246 194712 1 0 3 0x100083 ttyin getty 57824 292275 1 0 3 0x88 kqread sshd 84109 85983 36341 73 3 0x1100090 kqread syslogd 36341 173053 1 0 3 0x100082 netio syslogd 72222 318597 1 0 3 0x100080 kqread resolvd 31640 406590 72629 77 3 0x100092 kqread dhcpleased 98388 119547 72629 77 3 0x100092 kqread dhcpleased 72629 286262 1 0 3 0x80 kqread dhcpleased 93788 250291 0 0 3 0x14200 bored smr 93419 520922 0 0 2 0x14200 zerothread 30685 82459 0 0 3 0x14200 aiodoned aiodoned 73922 414178 0 0 3 0x14200 syncer update 96853 118616 0 0 3 0x14200 cleaner cleaner 43970 125193 0 0 7 0x14200 reaper 5855 264994 0 0 3 0x14200 pgdaemon pagedaemon 91761 338328 0 0 3 0x14200 bored viomb 14720 64083 0 0 3 0x40014200 acpi0 acpi0 80366 288748 0 0 3 0x40014200 idle1 98012 306549 0 0 3 0x14200 bored softnet 25967 224816 0 0 3 0x14200 bored systqmp 7795 44532 0 0 3 0x14200 bored systq 79532 226868 0 0 3 0x40014200 bored softclock 90964 327904 0 0 3 0x40014200 idle0 1 296527 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 22400 (syz-executor.2) thread 0xffff80002cd66fd0 (237978) 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 10172 6407K 6419K 78643K 11262 0 pcb 13 8K 8K 78643K 13 0 rtable 242 7K 7K 78643K 360 0 ifaddr 81 16K 16K 78643K 82 0 counters 56 35K 35K 78643K 56 0 ioctlops 0 0K 2K 78643K 35 0 iov 0 0K 12K 78643K 23 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 5 0 vnodes 1270 79K 79K 78643K 1285 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 1K 78643K 2 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 1K 78643K 172 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 20 73K 117K 78643K 426 0 proc 56 74K 111K 78643K 469 0 subproc 104 6K 6K 78643K 104 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 14 0 in_multi 99 6K 6K 78643K 105 0 ether_multi 1 0K 0K 78643K 1 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 49 228K 228K 78643K 49 0 exec 0 0K 2K 78643K 686 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 271 80K 81K 78643K 6818 0 UVM aobj 6 6K 6K 78643K 6 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 1 0K 0K 78643K 2 0 NDP 11 0K 2K 78643K 27 0 temp 114 4700K 4764K 78643K 4809 0 kqueue 12 18K 22K 78643K 55 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 53 0 50 1 0 1 1 0 8 0 rtentry 112 113 0 1 4 0 4 4 0 8 0 unpcb 136 203 0 190 3 0 3 3 0 8 2 syncache 296 18 0 18 2 1 1 1 0 8 1 tcpqe 32 111 0 111 1 0 1 1 0 8 1 tcpcb 736 264 0 185 10 2 8 8 0 8 0 arp 120 18 0 0 1 0 1 1 0 8 0 inpcb 304 821 0 807 7 1 6 7 0 8 4 nd6 48 26 0 0 1 0 1 1 0 8 0 kcovpl 48 8 0 0 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 467 0 0 30 0 30 30 0 8 0 art_table 32 468 0 0 4 0 4 4 0 8 0 art_node 16 112 0 10 1 0 1 1 0 8 0 semupl 112 2 0 2 1 0 1 1 0 8 1 semapl 112 166 0 156 1 0 1 1 0 8 0 shmpl 112 3 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1807 0 378 90 0 90 90 0 8 0 ffsino 272 1807 0 378 96 0 96 96 0 8 0 nchpl 144 2406 0 748 62 0 62 62 0 8 0 uvmvnodes 80 1920 0 0 40 0 40 40 0 8 0 vnodes 224 1920 0 0 113 0 113 113 0 8 0 namei 1024 7838 0 7838 2 1 1 2 0 8 1 percpumem 16 40 0 0 1 0 1 1 0 8 0 scxspl 216 7553 0 7553 9 1 8 8 0 8 8 plimitpl 152 59 0 37 1 0 1 1 0 8 0 sigapl 424 705 0 657 7 0 7 7 0 8 0 futexpl 64 3244 0 3243 1 0 1 1 0 8 0 knotepl 120 120 0 0 4 0 4 4 0 8 0 kqueuepl 216 203 0 195 5 0 5 5 0 8 4 pipepl 336 178 0 150 3 0 3 3 0 8 0 fdescpl 496 690 0 659 7 1 6 6 0 8 0 filepl 152 3490 0 3251 17 2 15 17 0 8 5 lockfpl 104 168 0 166 1 0 1 1 0 8 0 lockfspl 48 35 0 33 1 0 1 1 0 8 0 sessionpl 144 23 0 7 1 0 1 1 0 8 0 pgrppl 48 23 0 7 1 0 1 1 0 8 0 ucredpl 96 235 0 217 1 0 1 1 0 8 0 zombiepl 144 659 0 657 1 0 1 1 0 8 0 processpl 1064 705 0 657 5 1 4 4 0 8 0 procpl 672 1291 0 1230 7 0 7 7 0 8 1 sosppl 168 4 0 4 1 0 1 1 0 8 1 sockpl 480 1077 0 1047 25 13 12 20 0 8 8 mcl64k 65536 7 0 0 1 0 1 1 0 8 0 mcl16k 16384 5 0 0 1 0 1 1 0 8 0 mcl12k 12288 2 0 0 1 0 1 1 0 8 0 mcl9k 9216 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 9 0 0 2 0 2 2 0 8 0 mcl4k 4096 7 0 0 1 0 1 1 0 8 0 mcl2k2 2112 1 0 0 1 0 1 1 0 8 0 mcl2k 2048 149 0 0 18 0 18 18 0 8 0 mtagpl 96 2 0 0 1 0 1 1 0 8 0 mbufpl 256 420 0 0 26 0 26 26 0 8 0 bufpl 288 3889 0 136 269 0 269 269 0 8 0 anonpl 24 155128 0 142737 103 2 101 101 0 186 15 amapchunkpl 152 15628 0 14962 36 2 34 34 0 158 2 amappl16 200 1945 0 1613 31 2 29 30 0 8 8 amappl15 192 175 0 167 1 0 1 1 0 8 0 amappl14 184 13 0 10 1 0 1 1 0 8 0 amappl13 176 120 0 115 1 0 1 1 0 8 0 amappl12 168 62 0 57 1 0 1 1 0 8 0 amappl11 160 91 0 78 1 0 1 1 0 8 0 amappl10 152 71 0 66 1 0 1 1 0 8 0 amappl9 144 477 0 472 1 0 1 1 0 8 0 amappl8 136 652 0 600 2 0 2 2 0 8 0 amappl7 128 200 0 187 1 0 1 1 0 8 0 amappl6 120 197 0 176 2 1 1 2 0 8 0 amappl5 112 473 0 455 1 0 1 1 0 8 0 amappl4 104 864 0 836 2 1 1 2 0 8 0 amappl3 96 255 0 240 1 0 1 1 0 8 0 amappl2 88 560 0 515 3 1 2 3 0 8 0 amappl1 80 15395 0 14813 18 3 15 18 0 8 0 amappl 88 6390 0 6180 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 5 0 0 1 0 1 1 0 8 0 uaddrrnd 24 690 0 659 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 690 0 659 1 0 1 1 0 8 0 vmmpekpl 168 9736 0 9687 3 0 3 3 0 8 0 vmmpepl 168 66416 0 64158 123 2 121 122 0 357 3 vmsppl 368 689 0 658 4 0 4 4 0 8 0 rwobjpl 56 19302 0 16157 48 2 46 46 0 8 0 pdppl 4096 1387 0 1316 107 26 81 91 0 8 10 pvpl 32 387157 0 370089 251 9 242 251 0 265 87 pmappl 248 689 0 658 4 1 3 3 0 8 0 extentpl 40 58 0 38 1 0 1 1 0 8 0 phpool 112 667 0 31 19 0 19 19 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(fffffd80771cf1a0,1,0) at witness_checkorder+0x10b7 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd80771cf1a0,1,0) at witness_checkorder+0x10b7 sys/kern/subr_witness.c:1105 rw_enter_read(fffffd80771cf190) at rw_enter_read+0x66 sys/kern/kern_rwlock.c:112 uvmfault_lookup(ffff80002e396960,0) at uvmfault_lookup+0xd9 sys/uvm/uvm_fault.c:1758 uvm_fault_check(ffff80002e396960,ffff80002e396998,ffff80002e3969c0) at uvm_fault_check+0x3a sys/uvm/uvm_fault.c:674 uvm_fault(fffffd80771cf188,20000000,0,2) at uvm_fault+0x102 sys/uvm/uvm_fault.c:602 kpageflttrap(ffff80002e396af0,20000300) at kpageflttrap+0x209 kerntrap(ffff80002e396af0) 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,ffff80002e396da0) at ifioctl_get+0x2dd soo_ioctl(fffffd80697bc148,c0106924,ffff80002e396da0,ffff80002cd66fd0) at soo_ioctl+0x26c sys_ioctl(ffff80002cd66fd0,ffff80002e396eb8,ffff80002e396f10) at sys_ioctl+0x4a2 syscall(ffff80002e396f80) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff80002e396f80) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xe89fb7a5d80, 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+0x129 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff829de780) at __mp_lock+0x129 sys/kern/kern_lock.c:147 uvm_unmap_detach(ffff800021135c30,1) at uvm_unmap_detach+0x113 sys/uvm/uvm_map.c:1615 uvm_map_teardown(fffffd80771cfa28) at uvm_map_teardown+0x262 sys/uvm/uvm_map.c:2789 uvmspace_free(fffffd80771cfa28) at uvmspace_free+0xa6 sys/uvm/uvm_map.c:3685 reaper(ffff8000210f97a0) at reaper+0x18b sys/kern/kern_exit.c:457 end trace frame: 0x0, count: -8