witness: lock order reversal: 1st 0xffffffff8290fe50 netlock (netlock) 2nd 0xfffffd806a7cd760 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(fffffd806a7cd760,1,0) at witness_checkorder+0x10b7 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd806a7cd760,1,0) at witness_checkorder+0x10b7 sys/kern/subr_witness.c:1105 rw_enter_read(fffffd806a7cd750) at rw_enter_read+0x66 sys/kern/kern_rwlock.c:112 uvmfault_lookup(ffff80002609ee60,0) at uvmfault_lookup+0xd9 sys/uvm/uvm_fault.c:1758 uvm_fault_check(ffff80002609ee60,ffff80002609ee98,ffff80002609eec0) at uvm_fault_check+0x3a sys/uvm/uvm_fault.c:674 uvm_fault(fffffd806a7cd748,20000000,0,2) at uvm_fault+0x102 sys/uvm/uvm_fault.c:602 kpageflttrap(ffff80002609eff0,20000300) at kpageflttrap+0x209 kerntrap(ffff80002609eff0) 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,ffff80002609f2a0) at ifioctl_get+0x2dd soo_ioctl(fffffd806a99a8f8,c0106924,ffff80002609f2a0,ffff800021251ce8) at soo_ioctl+0x26c sys_ioctl(ffff800021251ce8,ffff80002609f3b8,ffff80002609f410) at sys_ioctl+0x4a2 syscall(ffff80002609f480) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff80002609f480) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x1b672ab7ba0, count: -15 ddb{0}> show registers rdi 0x3 rsi 0xffffffff8294abb0 __sancov_gen_cov_switch_values.134 rbp 0xffff80002609eb50 rbx 0x3 rdx 0 rcx 0 rax 0xffff800021251ce8 r8 0xffff80002609eac0 r9 0x8080808080808080 r10 0x175ebabbcfc55a73 r11 0x3098cb94691e001e r12 0xffffffff82ab0430 w_lodata+0x52ac0 r13 0 r14 0xffffffff82aa5900 w_lodata+0x47f90 r15 0xfffffd8002f62d80 rip 0xffffffff8138d658 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff80002609eb40 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor.0) pid=432588 stat=onproc flags process=10 proc=4000000 pri=32, usrpri=82, nice=20 forw=0xffffffffffffffff, list=0xffff8000211dfce0,0xffffffff82b3d400 process=0xffff800028749910 user=0xffff80002609a000, vmspace=0xfffffd806a7cd748 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 43351 468102 3093 32767 2 0x10 syz-executor.2 98864 372851 49653 32767 2 0x10 syz-executor.0 *98864 432588 49653 32767 7 0x4000010 syz-executor.0 65172 204427 58149 32767 2 0x10 syz-executor.7 65172 378931 58149 32767 2 0x4000010 syz-executor.7 67295 497536 87598 32767 3 0x90 nanoslp syz-executor.5 67295 143983 87598 32767 3 0x4000090 fsleep syz-executor.5 29651 244237 0 0 3 0x14200 bored sosplice 795 7710 64920 32767 3 0x90 nanoslp syz-executor.3 36920 156602 37414 32767 3 0x90 nanoslp syz-executor.6 58149 197641 83695 32767 3 0x90 nanoslp syz-executor.7 30861 331351 66539 32767 2 0x10 syz-executor.4 37414 481780 47661 0 3 0x82 wait syz-executor.6 83695 148472 47661 0 3 0x82 wait syz-executor.7 87598 134219 30686 32767 3 0x90 nanoslp syz-executor.5 66539 220254 47661 0 3 0x82 wait syz-executor.4 30686 330880 47661 0 3 0x82 wait syz-executor.5 49653 28948 87185 32767 3 0x90 nanoslp syz-executor.0 64920 171327 47661 0 3 0x82 wait syz-executor.3 3093 523199 80187 32767 3 0x90 nanoslp syz-executor.2 80176 159415 68315 32767 2 0x10 syz-executor.1 80187 66995 47661 0 3 0x82 wait syz-executor.2 68315 109645 47661 0 3 0x82 wait syz-executor.1 87185 79827 47661 0 3 0x82 wait syz-executor.0 47661 325539 51871 0 3 0x82 thrsleep syz-fuzzer 47661 477762 51871 0 3 0x4000082 nanoslp syz-fuzzer 47661 381118 51871 0 3 0x4000082 thrsleep syz-fuzzer 47661 51979 51871 0 2 0x4000002 syz-fuzzer 47661 424305 51871 0 3 0x4000082 thrsleep syz-fuzzer 47661 165914 51871 0 3 0x4000082 thrsleep syz-fuzzer 47661 361826 51871 0 3 0x4000082 kqread syz-fuzzer 47661 231372 51871 0 3 0x4000082 thrsleep syz-fuzzer 47661 206687 51871 0 3 0x4000082 thrsleep syz-fuzzer 51871 70778 91753 0 3 0x10008a sigsusp ksh 91753 217377 97217 0 3 0x9a kqread sshd 88396 171829 1 0 3 0x100083 ttyin getty 97217 508090 1 0 3 0x88 kqread sshd 56111 196781 82317 73 3 0x1100090 kqread syslogd 82317 60134 1 0 3 0x100082 netio syslogd 29494 115545 1 0 3 0x100080 kqread resolvd 52282 83119 56043 77 3 0x100092 kqread dhcpleased 51455 49578 56043 77 3 0x100092 kqread dhcpleased 56043 462860 1 0 3 0x80 kqread dhcpleased 90366 227817 0 0 3 0x14200 bored smr 25523 306985 0 0 2 0x14200 zerothread 2779 408303 0 0 3 0x14200 aiodoned aiodoned 82387 72791 0 0 3 0x14200 syncer update 61389 245429 0 0 3 0x14200 cleaner cleaner 46549 469461 0 0 7 0x14200 reaper 70211 37867 0 0 3 0x14200 pgdaemon pagedaemon 41022 68635 0 0 3 0x14200 bored viomb 2035 477929 0 0 3 0x40014200 acpi0 acpi0 77469 316458 0 0 3 0x40014200 idle1 90837 501366 0 0 2 0x14200 softnet 57204 522271 0 0 3 0x14200 bored systqmp 54130 434653 0 0 3 0x14200 bored systq 84502 326218 0 0 3 0x40014200 bored softclock 75081 134423 0 0 3 0x40014200 idle0 1 428322 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 98864 (syz-executor.0) thread 0xffff800021251ce8 (432588) 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 10173 6407K 6419K 78643K 11263 0 pcb 13 8K 8K 78643K 13 0 rtable 242 7K 7K 78643K 366 0 ifaddr 81 16K 16K 78643K 82 0 counters 56 35K 35K 78643K 56 0 ioctlops 0 0K 2K 78643K 45 0 iov 0 0K 16K 78643K 40 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 5 0 vnodes 1270 79K 79K 78643K 1341 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 9K 78643K 165 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 0K 78643K 148 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 22 81K 113K 78643K 1780 0 sigio 0 0K 0K 78643K 1 0 proc 56 74K 99K 78643K 537 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 4 0K 0K 78643K 594 0 in_multi 100 6K 6K 78643K 199 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 55 254K 254K 78643K 55 0 exec 0 0K 2K 78643K 666 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 305 81K 84K 78643K 23054 0 UVM aobj 131 6K 6K 78643K 131 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 18 0 NDP 11 0K 2K 78643K 27 0 temp 120 4705K 4769K 78643K 7500 0 kqueue 12 18K 22K 78643K 97 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 69 0 66 1 0 1 1 0 8 0 rtentry 112 114 0 2 4 0 4 4 0 8 0 unpcb 136 725 0 712 7 6 1 5 0 8 0 syncache 296 21 0 21 2 2 0 1 0 8 0 tcpqe 32 292 0 292 2 2 0 1 0 8 0 tcpcb 736 314 0 307 8 7 1 8 0 8 0 arp 120 19 0 0 1 0 1 1 0 8 0 ipq 40 2 0 2 1 1 0 1 0 8 0 ipqe 40 5 0 5 1 1 0 1 0 8 0 inpcb 304 805 0 790 17 11 6 7 0 8 4 ip6q 72 4 0 3 1 0 1 1 0 8 0 ip6af 40 7 0 6 1 0 1 1 0 8 0 nd6 48 26 0 1 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 256 458 0 3 29 0 29 29 0 8 0 art_table 32 459 0 3 4 0 4 4 0 8 0 art_node 16 113 0 11 1 0 1 1 0 8 0 sysvmsgpl 40 87 0 48 1 0 1 1 0 8 0 semupl 112 8 0 8 1 1 0 1 0 8 0 semapl 112 145 0 135 1 0 1 1 0 8 0 shmpl 112 128 0 0 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 3368 0 1938 90 0 90 90 0 8 0 ffsino 272 3368 0 1938 96 0 96 96 0 8 0 nchpl 144 5733 0 4068 62 0 62 62 0 8 0 uvmvnodes 80 3481 0 0 72 0 72 72 0 8 0 vnodes 224 3481 0 0 205 0 205 205 0 8 0 namei 1024 15933 0 15933 3 2 1 2 0 8 1 percpumem 16 40 0 0 1 0 1 1 0 8 0 scxspl 216 20799 0 20799 10 8 2 8 0 8 2 plimitpl 152 289 0 267 1 0 1 1 0 8 0 sigapl 424 2055 0 2005 7 1 6 7 0 8 0 futexpl 64 8770 0 8769 1 0 1 1 0 8 0 knotepl 120 187 0 0 6 0 6 6 0 8 0 kqueuepl 216 194 0 185 1 0 1 1 0 8 0 pipepl 336 275 0 247 7 4 3 7 0 8 0 fdescpl 496 2040 0 2007 7 2 5 6 0 8 0 filepl 152 7034 0 6792 20 8 12 16 0 8 2 lockfpl 104 95 0 93 1 0 1 1 0 8 0 lockfspl 48 34 0 32 1 0 1 1 0 8 0 sessionpl 144 23 0 7 1 0 1 1 0 8 0 pgrppl 48 27 0 11 1 0 1 1 0 8 0 ucredpl 96 1006 0 988 1 0 1 1 0 8 0 zombiepl 144 2007 0 2005 1 0 1 1 0 8 0 processpl 1064 2055 0 2005 5 1 4 4 0 8 0 procpl 672 4384 0 4322 9 2 7 7 0 8 1 sosppl 168 9 0 9 2 2 0 1 0 8 0 sockpl 480 1695 0 1665 42 31 11 20 0 8 7 mcl64k 65536 6 0 0 1 0 1 1 0 8 0 mcl16k 16384 5 0 0 1 0 1 1 0 8 0 mcl12k 12288 5 0 0 1 0 1 1 0 8 0 mcl9k 9216 3 0 0 1 0 1 1 0 8 0 mcl8k 8192 7 0 0 1 0 1 1 0 8 0 mcl4k 4096 10 0 0 2 0 2 2 0 8 0 mcl2k2 2112 4 0 0 1 0 1 1 0 8 0 mcl2k 2048 146 0 0 17 0 17 17 0 8 0 mtagpl 96 2 0 0 1 0 1 1 0 8 0 mbufpl 256 456 0 0 28 0 28 28 0 8 0 bufpl 288 6163 0 144 430 0 430 430 0 8 0 anonpl 24 508806 0 495211 135 34 101 131 0 186 12 amapchunkpl 152 54638 0 53888 49 15 34 44 0 158 3 amappl16 200 4640 0 4255 48 27 21 42 0 8 0 amappl15 192 89 0 82 1 0 1 1 0 8 0 amappl14 184 200 0 197 1 0 1 1 0 8 0 amappl13 176 319 0 315 1 0 1 1 0 8 0 amappl12 168 230 0 227 1 0 1 1 0 8 0 amappl11 160 48 0 38 1 0 1 1 0 8 0 amappl10 152 32 0 30 1 0 1 1 0 8 0 amappl9 144 1258 0 1247 1 0 1 1 0 8 0 amappl8 136 741 0 689 2 0 2 2 0 8 0 amappl7 128 303 0 289 1 0 1 1 0 8 0 amappl6 120 1055 0 1023 2 1 1 2 0 8 0 amappl5 112 1777 0 1758 1 0 1 1 0 8 0 amappl4 104 800 0 774 2 1 1 2 0 8 0 amappl3 96 406 0 391 1 0 1 1 0 8 0 amappl2 88 979 0 933 3 1 2 3 0 8 0 amappl1 80 37126 0 36512 19 5 14 18 0 8 0 amappl 88 22607 0 22365 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 72 130 0 0 3 0 3 3 0 8 0 uaddrrnd 24 2040 0 2006 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 2040 0 2006 1 0 1 1 0 8 0 vmmpekpl 168 16763 0 16706 3 0 3 3 0 8 0 vmmpepl 168 183220 0 180671 144 21 123 138 0 357 5 vmsppl 368 2039 0 2005 4 0 4 4 0 8 0 rwobjpl 56 45890 0 40978 71 1 70 70 0 8 0 pdppl 4096 4087 0 4010 106 25 81 89 0 8 4 pvpl 32 975662 0 956902 262 57 205 252 0 265 46 pmappl 248 2039 0 2005 4 1 3 3 0 8 0 extentpl 40 58 0 38 1 0 1 1 0 8 0 phpool 112 830 0 40 23 0 23 23 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(fffffd806a7cd760,1,0) at witness_checkorder+0x10b7 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd806a7cd760,1,0) at witness_checkorder+0x10b7 sys/kern/subr_witness.c:1105 rw_enter_read(fffffd806a7cd750) at rw_enter_read+0x66 sys/kern/kern_rwlock.c:112 uvmfault_lookup(ffff80002609ee60,0) at uvmfault_lookup+0xd9 sys/uvm/uvm_fault.c:1758 uvm_fault_check(ffff80002609ee60,ffff80002609ee98,ffff80002609eec0) at uvm_fault_check+0x3a sys/uvm/uvm_fault.c:674 uvm_fault(fffffd806a7cd748,20000000,0,2) at uvm_fault+0x102 sys/uvm/uvm_fault.c:602 kpageflttrap(ffff80002609eff0,20000300) at kpageflttrap+0x209 kerntrap(ffff80002609eff0) 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,ffff80002609f2a0) at ifioctl_get+0x2dd soo_ioctl(fffffd806a99a8f8,c0106924,ffff80002609f2a0,ffff800021251ce8) at soo_ioctl+0x26c sys_ioctl(ffff800021251ce8,ffff80002609f3b8,ffff80002609f410) at sys_ioctl+0x4a2 syscall(ffff80002609f480) at syscall+0x489 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff80002609f480) at syscall+0x489 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x1b672ab7ba0, 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 uvm_unmap_detach(ffff8000211355e0,1) at uvm_unmap_detach+0x113 sys/uvm/uvm_map.c:1615 uvm_map_teardown(fffffd806a7cd8b8) at uvm_map_teardown+0x262 sys/uvm/uvm_map.c:2789 uvmspace_free(fffffd806a7cd8b8) 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