panic: kernel diagnostic assertion "dtlookup(unit) == NULL" failed: file "/syzkaller/managers/main/kernel/sys/dev/dt/dt_dev.c", line 168 Stopped at db_enter+0x1c: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *327245 25730 0 0 0x4000000 0 syz-executor.5 db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff8278714d) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff82802b97,ffffffff82828b00,a8,ffffffff827a9a50) at __assert+0x29 sys/kern/subr_prf.c:157 dtopen(21e5f,1,2000,ffff800035e09540) at dtopen+0x1d4 sys/dev/dt/dt_dev.c:168 spec_open_clone(ffff800034a4da08) at spec_open_clone+0x208 spec_open(ffff800034a4da08) at spec_open+0x401 sys/kern/spec_vnops.c:148 VOP_OPEN(fffffd80664cd7b0,1,fffffd807f7d7af8,ffff800035e09540) at VOP_OPEN+0x70 sys/kern/vfs_vops.c:138 vn_open(ffff800034a4dc58,1,0) at vn_open+0x452 sys/kern/vfs_vnops.c:177 doopenat(ffff800035e09540,ffffff9c,20000000,0,0,ffff800034a4de30) at doopenat+0x26e sys/kern/vfs_syscalls.c:1126 syscall(ffff800034a4dea0) at syscall+0x543 sys/arch/amd64/amd64/trap.c:606 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x3c093c77a20, count: 4 https://www.openbsd.org/ddb.html describes the minimum info required in bug reports. Insufficient info makes it difficult to find and fix bugs. ddb> ddb> set $lines = 0 ddb> set $maxwidth = 0 ddb> show panic *cpu0: kernel diagnostic assertion "dtlookup(unit) == NULL" failed: file "/syzkaller/managers/main/kernel/sys/dev/dt/dt_dev.c", line 168 ddb> trace db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff8278714d) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff82802b97,ffffffff82828b00,a8,ffffffff827a9a50) at __assert+0x29 sys/kern/subr_prf.c:157 dtopen(21e5f,1,2000,ffff800035e09540) at dtopen+0x1d4 sys/dev/dt/dt_dev.c:168 spec_open_clone(ffff800034a4da08) at spec_open_clone+0x208 spec_open(ffff800034a4da08) at spec_open+0x401 sys/kern/spec_vnops.c:148 VOP_OPEN(fffffd80664cd7b0,1,fffffd807f7d7af8,ffff800035e09540) at VOP_OPEN+0x70 sys/kern/vfs_vops.c:138 vn_open(ffff800034a4dc58,1,0) at vn_open+0x452 sys/kern/vfs_vnops.c:177 doopenat(ffff800035e09540,ffffff9c,20000000,0,0,ffff800034a4de30) at doopenat+0x26e sys/kern/vfs_syscalls.c:1126 syscall(ffff800034a4dea0) at syscall+0x543 sys/arch/amd64/amd64/trap.c:606 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x3c093c77a20, count: -11 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff800034a4d7e0 rbx 0 rdx 0xffff800000d04a80 rcx 0 rax 0xffff800035e09540 r8 0x101010101010101 r9 0x8080808080808080 r10 0x168e231a60151057 r11 0x69fc7cb2ba2538a3 r12 0 r13 0xffff800000d0fc00 r14 0 r15 0x1 rip 0xffffffff824ed06c db_enter+0x1c cs 0x8 rflags 0x246 rsp 0xffff800034a4d7d0 ss 0x10 db_enter+0x1c: addq $0x8,%rsp ddb> show proc PROC (syz-executor.5) tid=327245 pid=25730 tcnt=2 stat=onproc flags process=0 proc=4000000 runpri=83, usrpri=83, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 forw=0xffffffffffffffff, list=0xffff800035e08ff0,0xffff800035e08010 process=0xffff8000378dcfc0 user=0xffff800034a48000, vmspace=0xfffffd8067d7a8b0 estcpu=33, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 57108 111721 21131 0 2 0 syz-executor.3 57108 298973 21131 0 3 0x4000080 fsleep syz-executor.3 3219 112226 6847 0 2 0 syz-executor.4 3219 474752 6847 0 3 0x4000080 fsleep syz-executor.4 15618 81538 95862 0 2 0 syz-executor.2 15618 376370 95862 0 3 0x4000080 fsleep syz-executor.2 25730 519526 5629 0 2 0 syz-executor.5 *25730 327245 5629 0 7 0x4000000 syz-executor.5 83604 293665 31858 0 2 0 syz-executor.0 83604 5088 31858 0 3 0x4000080 fsleep syz-executor.0 83604 187203 31858 0 3 0x4000080 fsleep syz-executor.0 99413 129862 61269 0 2 0 syz-executor.7 99413 467949 61269 0 3 0x4000080 fsleep syz-executor.7 99413 9930 61269 0 3 0x4000080 fsleep syz-executor.7 96467 446893 55746 0 2 0 syz-executor.6 96467 493923 55746 0 3 0x4000080 fsleep syz-executor.6 96467 498846 55746 0 3 0x4000080 fsleep syz-executor.6 96467 243699 55746 0 3 0x4000080 fsleep syz-executor.6 44834 505358 50456 0 2 0 syz-executor.1 44834 239191 50456 0 3 0x4000080 fifor syz-executor.1 44834 407474 50456 0 3 0x4000080 fsleep syz-executor.1 44834 45503 50456 0 3 0x4000080 fsleep syz-executor.1 44834 44911 50456 0 3 0x4000080 fsleep syz-executor.1 31858 307272 45027 0 3 0x82 nanoslp syz-executor.0 6847 25306 45027 0 3 0x82 nanoslp syz-executor.4 50456 260994 45027 0 3 0x82 nanoslp syz-executor.1 61269 490073 45027 0 3 0x82 nanoslp syz-executor.7 21131 465699 45027 0 3 0x82 nanoslp syz-executor.3 55746 466500 45027 0 3 0x82 nanoslp syz-executor.6 35460 119594 0 0 3 0x14200 bored sosplice 32654 442204 0 0 3 0x14280 nfsidl nfsio 22283 300489 0 0 3 0x14280 nfsidl nfsio 40890 439514 0 0 3 0x14280 nfsidl nfsio 13225 327712 0 0 3 0x14280 nfsidl nfsio 91518 217341 0 0 3 0x14280 nfsidl nfsio 19295 97586 0 0 3 0x14280 nfsidl nfsio 42529 283294 0 0 3 0x14280 nfsidl nfsio 82442 348830 0 0 3 0x14280 nfsidl nfsio 30915 272148 0 0 3 0x14280 nfsidl nfsio 19931 386741 0 0 3 0x14280 nfsidl nfsio 54014 366617 0 0 3 0x14280 nfsidl nfsio 45200 442260 0 0 3 0x14280 nfsidl nfsio 5239 476283 0 0 3 0x14280 nfsidl nfsio 10264 240852 0 0 3 0x14280 nfsidl nfsio 42955 73669 0 0 3 0x14280 nfsidl nfsio 25130 519266 0 0 3 0x14280 nfsidl nfsio 55938 348906 0 0 3 0x14280 nfsidl nfsio 86262 35450 0 0 3 0x14280 nfsidl nfsio 85793 508880 0 0 3 0x14280 nfsidl nfsio 66325 456059 0 0 3 0x14280 nfsidl nfsio 5629 248860 45027 0 3 0x82 nanoslp syz-executor.5 95862 164689 45027 0 3 0x82 nanoslp syz-executor.2 45027 244821 88235 0 3 0x2000082 wait syz-fuzzer 45027 90911 88235 0 3 0x6000082 thrsleep syz-fuzzer 45027 67491 88235 0 3 0x6000082 wait syz-fuzzer 45027 285874 88235 0 3 0x6000082 thrsleep syz-fuzzer 45027 372653 88235 0 3 0x6000082 wait syz-fuzzer 45027 507914 88235 0 3 0x6000082 thrsleep syz-fuzzer 45027 148060 88235 0 3 0x6000082 wait syz-fuzzer 45027 73974 88235 0 3 0x6000082 wait syz-fuzzer 45027 254230 88235 0 3 0x6000082 kqread syz-fuzzer 45027 80953 88235 0 3 0x6000082 wait syz-fuzzer 45027 18869 88235 0 3 0x6000082 thrsleep syz-fuzzer 45027 144681 88235 0 3 0x6000082 wait syz-fuzzer 45027 473456 88235 0 3 0x6000082 wait syz-fuzzer 45027 484871 88235 0 3 0x6000082 thrsleep syz-fuzzer 88235 296619 86045 0 3 0x10008a sigsusp ksh 86045 4492 5386 0 3 0x9a kqread sshd 55549 177334 1 0 3 0x100083 ttyin getty 5386 298192 1 0 3 0x88 kqread sshd 9835 168499 17818 73 3 0x1100090 kqread syslogd 17818 432828 1 0 3 0x100082 netio syslogd 73405 9367 1 0 3 0x100080 kqread resolvd 84733 48106 64474 77 3 0x100092 kqread dhcpleased 62667 72197 64474 77 3 0x100092 kqread dhcpleased 64474 280811 1 0 3 0x80 kqread dhcpleased 46277 297931 0 0 3 0x14200 bored smr 16925 66958 0 0 2 0x14200 zerothread 65908 282882 0 0 3 0x14200 aiodoned aiodoned 82205 208881 0 0 3 0x14200 syncer update 29269 152176 0 0 3 0x14200 cleaner cleaner 60569 82680 0 0 3 0x14200 reaper reaper 19021 118906 0 0 3 0x14200 pgdaemon pagedaemon 76581 126590 0 0 3 0x14200 bored viomb 56326 411763 0 0 3 0x40014200 acpi0 acpi0 28123 361313 0 0 3 0x14200 bored softnet3 95271 291578 0 0 3 0x14200 bored softnet2 74942 442823 0 0 3 0x14200 bored softnet1 64755 324229 0 0 3 0x14200 bored softnet0 9335 389107 0 0 3 0x14200 bored systqmp 25385 182776 0 0 3 0x14200 bored systq 306 214887 0 0 3 0x40014200 tmoslp softclock 32559 288061 0 0 3 0x40014200 idle0 1 302173 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb> show all locks No such command ddb> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10214 6520K 6923K 166960K 15944 0 pcb 13 14K 16K 166960K 388 0 rtable 196 8K 9K 166960K 704 0 pf 29 8K 9K 166960K 125 0 ifaddr 41 11K 12K 166960K 119 0 ifgroup 50 2K 2K 166960K 174 0 sysctl 3 0K 0K 166960K 3 0 counters 30 17K 17K 166960K 75 0 ioctlops 0 0K 2K 166960K 205 0 iov 0 0K 32K 166960K 614 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1454 91K 91K 166960K 3224 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 31 0 VM map 2 1K 1K 166960K 2 0 sem 10 1K 1K 166960K 18 0 dirhash 12 2K 2K 166960K 21 0 ACPI 1697 195K 286K 166960K 12548 0 file desc 18 65K 73K 166960K 3092 0 sigio 0 0K 0K 166960K 158 0 proc 57 59K 75K 166960K 797 0 subproc 104 6K 6K 166960K 197 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 50 0 in_multi 77 5K 7K 166960K 188 0 ether_multi 1 0K 0K 166960K 1 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 217 970K 970K 166960K 217 0 exec 0 0K 1K 166960K 913 0 pfkey data 0 0K 0K 166960K 2 0 tdb 3 0K 0K 166960K 3 0 pagedep 1 8K 8K 166960K 1 0 inodedep 1 32K 32K 166960K 1 0 newblk 1 0K 0K 166960K 1 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 392 189K 198K 166960K 30986 0 UVM aobj 131 4K 4K 166960K 131 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 171 0 NDP 11 0K 2K 166960K 86 0 temp 75 5920K 5996K 166960K 40848 0 kqueue 12 18K 26K 166960K 226 0 SYN cache 2 16K 16K 166960K 2 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle rtpcb 120 253 0 250 3 2 1 3 0 8 0 rtentry 112 194 0 106 4 0 4 4 0 8 0 unpcb 144 1565 0 1550 20 19 1 6 0 8 0 syncache 312 32 0 32 6 6 0 1 0 8 0 tcpqe 32 151 0 151 5 5 0 1 0 8 0 tcpcb 808 761 0 757 24 21 3 12 0 8 2 arp 88 34 0 20 1 0 1 1 0 8 0 ipq 40 2 0 2 2 2 0 1 0 8 0 ipqe 40 9 0 9 2 2 0 1 0 8 0 inpcb 336 1962 0 1955 41 37 4 16 0 8 3 nd6 104 46 0 28 1 0 1 1 0 8 0 pkpcb 40 136 0 136 2 2 0 1 0 8 0 kcovpl 48 15 0 7 1 0 1 1 0 8 0 ppxss 1160 31 0 31 5 5 0 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 773 0 403 33 9 24 29 0 8 0 art_table 32 774 0 403 4 0 4 4 0 8 0 art_node 16 190 0 110 1 0 1 1 0 8 0 sysvmsgpl 40 15 0 7 1 0 1 1 0 8 0 semupl 112 8 0 8 1 1 0 1 0 8 0 semapl 112 8 0 0 1 0 1 1 0 8 0 shmpl 112 128 0 0 4 0 4 4 0 8 0 dirhash 1024 23 0 6 3 0 3 3 0 8 0 dino2pl 256 5668 0 4214 92 0 92 92 0 8 0 ffsino 240 5668 0 4214 86 0 86 86 0 8 0 nchpl 144 11030 0 9377 63 0 63 63 0 8 0 uvmvnodes 80 5926 0 0 121 0 121 121 0 8 0 vnodes 216 5926 0 0 330 0 330 330 0 8 0 namei 1024 38699 0 38699 4 3 1 2 0 8 1 vcpupl 2048 73 0 0 10 0 10 10 0 8 0 vmpool 664 79 0 6 7 0 7 7 0 8 0 kstatmem 264 112 0 90 2 0 2 2 0 8 0 scxspl 216 29081 0 29081 13 12 1 8 1 8 1 plimitpl 152 453 0 437 1 0 1 1 0 8 0 sigapl 424 3400 0 3334 8 0 8 8 0 8 0 futexpl 64 29791 0 29778 1 0 1 1 0 8 0 knotepl 120 41826 0 41746 20 8 12 15 0 8 8 kqueuepl 184 581 0 573 10 9 1 4 0 8 0 pipepl 288 897 0 868 11 8 3 7 0 8 0 fdescpl 432 3362 0 3333 4 0 4 4 0 8 0 filepl 120 23424 0 23178 41 32 9 19 0 8 1 lockfpl 104 898 0 896 3 2 1 2 0 8 0 lockfspl 48 322 0 320 1 0 1 1 0 8 0 sessionpl 144 30 0 14 1 0 1 1 0 8 0 pgrppl 48 104 0 88 1 0 1 1 0 8 0 ucredpl 104 3416 0 3406 1 0 1 1 0 8 0 zombiepl 144 3669 0 3669 2 1 1 1 0 8 1 processpl 1008 3400 0 3334 10 1 9 9 0 8 0 procpl 680 8075 0 7981 11 2 9 9 0 8 0 sosppl 168 29 0 29 4 3 1 1 0 8 1 sockpl 456 3916 0 3891 90 81 9 26 0 8 5 mcl64k 65536 164 0 164 3 2 1 1 0 8 1 mcl16k 16384 65 0 65 9 8 1 1 0 8 1 mcl12k 12288 125 0 125 8 7 1 1 0 8 1 mcl9k 9216 42 0 42 7 7 0 1 0 8 0 mcl8k 8192 168 0 168 4 3 1 1 0 8 1 mcl4k 4096 310 0 310 4 3 1 1 0 8 1 mcl2k2 2112 20 0 20 9 8 1 1 0 8 1 mcl2k 2048 73195 0 73155 39 32 7 31 0 8 1 mtagpl 96 422 0 348 6 1 5 5 0 8 0 mbufpl 256 146037 0 145871 211 184 27 108 0 8 6 bufpl 288 9321 0 2927 457 0 457 457 0 8 0 anonpl 24 456640 0 443605 97 7 90 94 0 188 0 amapchunkpl 152 99252 0 98291 49 12 37 41 0 158 0 amappl16 200 9909 0 9499 29 6 23 25 0 8 1 amappl15 192 17 0 17 1 1 0 1 0 8 0 amappl14 184 174 0 163 2 1 1 2 0 8 0 amappl13 176 19 0 19 2 2 0 1 0 8 0 amappl12 168 4095 0 4063 2 0 2 2 0 8 0 amappl11 160 57 0 46 1 0 1 1 0 8 0 amappl10 152 34 0 22 1 0 1 1 0 8 0 amappl9 144 137 0 136 2 1 1 1 0 8 0 amappl8 136 251 0 181 3 0 3 3 0 8 0 amappl7 128 200 0 178 2 0 2 2 0 8 0 amappl6 120 372 0 363 1 0 1 1 0 8 0 amappl5 112 209 0 201 1 0 1 1 0 8 0 amappl4 104 493 0 467 2 1 1 2 0 8 0 amappl3 96 19786 0 19679 3 0 3 3 0 8 0 amappl2 88 3915 0 3839 3 0 3 3 0 8 0 amappl1 80 20578 0 20074 22 9 13 22 0 8 0 amappl 88 30350 0 30088 6 0 6 6 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 3441 0 3339 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 3441 0 3339 1 0 1 1 0 8 0 vmmpekpl 168 28808 0 28733 4 0 4 4 0 8 0 vmmpepl 168 217005 0 214539 183 63 120 125 0 357 12 vmsppl 368 3440 0 3339 10 0 10 10 0 8 0 rwobjpl 24 63110 0 55581 46 0 46 46 0 8 0 pdppl 4096 6888 0 6751 335 198 137 137 0 8 0 pvpl 32 1119364 0 1100600 352 189 163 333 0 265 1 pmappl 216 3440 0 3339 6 0 6 6 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 1397 0 518 28 0 28 28 0 8 0 ddb> machine ddbcpu 0 No such command ddb> trace db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff8278714d) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff82802b97,ffffffff82828b00,a8,ffffffff827a9a50) at __assert+0x29 sys/kern/subr_prf.c:157 dtopen(21e5f,1,2000,ffff800035e09540) at dtopen+0x1d4 sys/dev/dt/dt_dev.c:168 spec_open_clone(ffff800034a4da08) at spec_open_clone+0x208 spec_open(ffff800034a4da08) at spec_open+0x401 sys/kern/spec_vnops.c:148 VOP_OPEN(fffffd80664cd7b0,1,fffffd807f7d7af8,ffff800035e09540) at VOP_OPEN+0x70 sys/kern/vfs_vops.c:138 vn_open(ffff800034a4dc58,1,0) at vn_open+0x452 sys/kern/vfs_vnops.c:177 doopenat(ffff800035e09540,ffffff9c,20000000,0,0,ffff800034a4de30) at doopenat+0x26e sys/kern/vfs_syscalls.c:1126 syscall(ffff800034a4dea0) at syscall+0x543 sys/arch/amd64/amd64/trap.c:606 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x3c093c77a20, count: -11 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff8278714d) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff82802b97,ffffffff82828b00,a8,ffffffff827a9a50) at __assert+0x29 sys/kern/subr_prf.c:157 dtopen(21e5f,1,2000,ffff800035e09540) at dtopen+0x1d4 sys/dev/dt/dt_dev.c:168 spec_open_clone(ffff800034a4da08) at spec_open_clone+0x208 spec_open(ffff800034a4da08) at spec_open+0x401 sys/kern/spec_vnops.c:148 VOP_OPEN(fffffd80664cd7b0,1,fffffd807f7d7af8,ffff800035e09540) at VOP_OPEN+0x70 sys/kern/vfs_vops.c:138 vn_open(ffff800034a4dc58,1,0) at vn_open+0x452 sys/kern/vfs_vnops.c:177 doopenat(ffff800035e09540,ffffff9c,20000000,0,0,ffff800034a4de30) at doopenat+0x26e sys/kern/vfs_syscalls.c:1126 syscall(ffff800034a4dea0) at syscall+0x543 sys/arch/amd64/amd64/trap.c:606 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x3c093c77a20, count: -11