login: panic: kernel diagnostic assertion "ifp != NULL" failed: file "/syzkaller/managers/main/kernel/sys/netinet/if_ether.c", line 776 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *405685 77495 0 0x14000 0x40000200 0 softclock db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff82724846) at panic+0x161 sys/kern/subr_prf.c:198 __assert(ffffffff827a2ca7,ffffffff827c31cb,308,ffffffff826f47ef) at __assert+0x25 sys/kern/subr_prf.c:157 arptfree(fffffd807ca0c470) at arptfree+0x12d sys/netinet/if_ether.c:776 arptimer(ffffffff82c104b0) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82c104b0) at timeout_run+0x8b sys/kern/kern_timeout.c:641 softclock_thread(ffff8000ffffeae0) at softclock_thread+0xf4 sys/kern/kern_timeout.c:765 end trace frame: 0x0, count: 8 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 "ifp != NULL" failed: file "/syzkaller/managers/main/kernel/sys/netinet/if_ether.c", line 776 ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff82724846) at panic+0x161 sys/kern/subr_prf.c:198 __assert(ffffffff827a2ca7,ffffffff827c31cb,308,ffffffff826f47ef) at __assert+0x25 sys/kern/subr_prf.c:157 arptfree(fffffd807ca0c470) at arptfree+0x12d sys/netinet/if_ether.c:776 arptimer(ffffffff82c104b0) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82c104b0) at timeout_run+0x8b sys/kern/kern_timeout.c:641 softclock_thread(ffff8000ffffeae0) at softclock_thread+0xf4 sys/kern/kern_timeout.c:765 end trace frame: 0x0, count: -7 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff800021604180 rbx 0 rdx 0 rcx 0 rax 0xffff8000ffffeae0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x96fc0f0376366233 r11 0x6e15ba385b5caf7f r12 0 r13 0xfffffd806eaef6e0 r14 0 r15 0x1 rip 0xffffffff821a5028 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800021604170 ss 0 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (softclock) pid=405685 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff8000ffffed98,0xffff8000ffffe838 process=0xffff8000ffffc3f0 user=0xffff8000215ff000, vmspace=0xffffffff82c32588 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 99994 76602 40937 0 2 0 syz-executor.2 99994 246575 40937 0 3 0x4000000 clonelk syz-executor.2 99994 206049 40937 0 3 0x4000080 fsleep syz-executor.2 54482 445249 1 0 3 0x100083 ttyin getty 16679 314190 86890 0 3 0x82 piperd syz-executor.4 32443 186720 86890 0 3 0x82 piperd syz-executor.7 56066 306737 86890 0 2 0x482 syz-executor.5 40937 256099 86890 0 2 0x482 syz-executor.2 6939 448534 0 0 3 0x14200 bored sosplice 81107 314721 86890 0 3 0x82 piperd syz-executor.6 84540 336961 86890 0 3 0x82 piperd syz-executor.3 79044 139130 86890 0 3 0x82 piperd syz-executor.1 86890 474359 20983 0 3 0x82 kqread syz-fuzzer 86890 353682 20983 0 3 0x4000082 thrsleep syz-fuzzer 86890 282226 20983 0 3 0x4000082 wait syz-fuzzer 86890 461329 20983 0 3 0x4000082 thrsleep syz-fuzzer 86890 363180 20983 0 3 0x4000082 wait syz-fuzzer 86890 363131 20983 0 3 0x4000082 thrsleep syz-fuzzer 86890 262210 20983 0 3 0x4000082 wait syz-fuzzer 86890 461597 20983 0 3 0x4000082 wait syz-fuzzer 86890 232864 20983 0 3 0x4000082 thrsleep syz-fuzzer 86890 264536 20983 0 3 0x4000082 wait syz-fuzzer 86890 463948 20983 0 3 0x4000082 thrsleep syz-fuzzer 86890 235461 20983 0 3 0x4000082 wait syz-fuzzer 86890 187313 20983 0 3 0x4000082 wait syz-fuzzer 86890 312218 20983 0 3 0x4000082 wait syz-fuzzer 86890 152284 20983 0 3 0x4000082 thrsleep syz-fuzzer 20983 124107 74747 0 3 0x10008a sigsusp ksh 74747 340892 87402 0 3 0x9a kqread sshd 87402 17249 1 0 3 0x88 kqread sshd 47426 74707 67233 73 3 0x1100090 kqread syslogd 67233 369802 1 0 3 0x100082 netio syslogd 68660 197583 1 0 3 0x100080 kqread resolvd 23389 240248 89554 77 3 0x100092 kqread dhcpleased 66693 134986 89554 77 3 0x100092 kqread dhcpleased 89554 317565 1 0 3 0x80 kqread dhcpleased 83227 363865 0 0 2 0x14200 smr 40393 55254 0 0 2 0x14200 zerothread 46915 8112 0 0 3 0x14200 aiodoned aiodoned 79495 489769 0 0 2 0x14600 update 35515 390446 0 0 3 0x14200 cleaner cleaner 26853 373877 0 0 3 0x14200 reaper reaper 70373 15289 0 0 3 0x14200 pgdaemon pagedaemon 94952 458848 0 0 3 0x14200 bored viomb 4563 65162 0 0 3 0x40014200 acpi0 acpi0 72625 251766 0 0 3 0x14200 bored softnet 47796 149688 0 0 3 0x14200 bored softnet 88263 345261 0 0 3 0x14200 bored softnet 3117 168353 0 0 3 0x14200 bored softnet 24302 171160 0 0 3 0x14200 bored systqmp 4268 441080 0 0 3 0x14200 bored systq *77495 405685 0 0 7 0x40014200 softclock 83294 16913 0 0 3 0x40014200 idle0 1 492459 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 10220 6427K 6799K 78643K 17460 0 pcb 13 18K 22K 78643K 852 0 rtable 173 6K 8K 78643K 1273 0 ifaddr 72 21K 24K 78643K 493 0 sysctl 2 0K 0K 78643K 4 0 counters 26 17K 17K 78643K 174 0 ioctlops 0 0K 4K 78643K 693 0 iov 0 0K 20K 78643K 390 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1553 97K 98K 78643K 4599 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 9K 78643K 45 0 VM map 2 1K 1K 78643K 2 0 sem 13 1K 2K 78643K 17 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 12 41K 69K 78643K 4254 0 sigio 0 0K 0K 78643K 162 0 proc 61 59K 83K 78643K 1041 0 subproc 104 6K 6K 78643K 299 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 632 0 in_multi 70 4K 7K 78643K 416 0 ether_multi 1 0K 0K 78643K 33 0 mrt 2 0K 0K 78643K 12 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 247 1102K 1102K 78643K 247 0 exec 0 0K 1K 78643K 1107 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 8 62K 64K 78643K 10 0 UVM amap 284 87K 102K 78643K 29003 0 UVM aobj 131 4K 4K 78643K 132 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 125 0 NDP 11 0K 1K 78643K 155 0 temp 123 5770K 39562K 78643K 37029 0 kqueue 12 18K 28K 78643K 411 0 SYN cache 2 16K 16K 78643K 2 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle rtpcb 120 528 0 525 8 7 1 3 0 8 0 rtentry 112 371 0 298 4 1 3 4 0 8 0 unpcb 144 8205 0 8190 70 61 9 13 0 8 8 syncache 296 24 0 24 6 6 0 1 0 8 0 tcpqe 32 165 0 165 5 5 0 1 0 8 0 tcpcb 776 1570 0 1566 62 55 7 14 0 8 6 arp 88 54 0 41 1 0 1 1 0 8 0 ipq 40 1 0 1 1 0 1 1 0 8 1 ipqe 40 4 0 4 1 0 1 1 0 8 1 inpcb 336 7457 0 7450 84 77 7 15 0 8 6 nd6 48 74 0 59 1 0 1 1 0 8 0 pkpcb 40 89 0 89 4 4 0 1 0 8 0 kcovpl 48 23 0 15 1 0 1 1 0 8 0 mppekey 1024 10 0 10 1 1 0 1 0 8 0 ppxss 1160 84 0 83 10 9 1 1 0 8 0 pppxif 1360 44 0 44 6 6 0 1 0 8 0 pfstscr 40 31 0 24 2 1 1 1 0 8 0 pfanchor 1280 545 68 33 43 0 43 43 0 8 0 pftag 88 1 0 0 1 0 1 1 0 8 0 pfqueue 264 3 0 0 1 0 1 1 0 8 0 pfstitem 24 8 0 0 1 0 1 1 0 8 0 pfstkey 128 50 0 46 2 1 1 1 0 8 0 pfstate 352 25 0 21 2 1 1 1 0 8 0 rttmr 136 3 0 3 1 1 0 1 0 8 0 art_heap8 4096 2 0 1 2 1 1 2 0 8 0 art_heap4 256 1644 0 1301 38 13 25 30 0 8 0 art_table 32 1646 0 1302 4 0 4 4 0 8 0 art_node 16 366 0 303 1 0 1 1 0 8 0 sysvmsgpl 40 9 0 7 1 0 1 1 0 8 0 semupl 112 7 0 7 1 1 0 1 0 8 0 semapl 112 11 0 0 1 0 1 1 0 8 0 shmpl 112 129 0 1 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 7145 0 5717 90 0 90 90 0 8 0 ffsino 240 7145 0 5717 85 0 85 85 0 8 0 nchpl 144 12901 0 11273 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 50422 0 50422 4 3 1 3 0 8 1 vmpool 664 15 0 15 4 4 0 1 0 8 0 kstatmem 264 210 0 188 2 0 2 2 0 8 0 scsiplug 72 9 0 9 3 3 0 1 0 8 0 scxspl 216 35921 0 35921 12 10 2 8 0 8 2 plimitpl 152 926 0 911 1 0 1 1 0 8 0 sigapl 424 4581 0 4541 8 0 8 8 0 8 0 futexpl 64 47492 0 47491 1 0 1 1 0 8 0 knotepl 120 69143 0 69065 31 27 4 9 0 8 0 kqueuepl 184 975 0 967 12 11 1 4 0 8 0 pipepl 288 1390 0 1363 28 25 3 7 0 8 0 fdescpl 432 4504 0 4481 4 0 4 4 0 8 0 filepl 120 43238 0 43001 66 49 17 22 0 8 8 lockfpl 104 947 0 945 3 2 1 2 0 8 0 lockfspl 48 258 0 256 1 0 1 1 0 8 0 sessionpl 144 40 0 24 1 0 1 1 0 8 0 pgrppl 48 119 0 103 1 0 1 1 0 8 0 ucredpl 104 4041 0 4027 1 0 1 1 0 8 0 zombiepl 144 4543 0 4541 2 1 1 1 0 8 0 processpl 1008 4581 0 4541 10 3 7 9 0 8 0 procpl 696 11116 0 11060 11 3 8 10 0 8 0 sosppl 168 47 0 47 5 5 0 1 0 8 0 sockpl 456 16284 0 16259 398 368 30 45 0 8 26 mcl64k 65536 117 0 117 12 11 1 1 0 8 1 mcl16k 16384 152 0 152 9 8 1 1 0 8 1 mcl12k 12288 150 0 150 10 9 1 1 0 8 1 mcl9k 9216 68 0 68 9 9 0 1 0 8 0 mcl8k 8192 290 0 290 6 5 1 1 0 8 1 mcl4k 4096 544 0 544 4 3 1 1 0 8 1 mcl2k2 2112 43 0 43 8 7 1 1 0 8 1 mcl2k 2048 84410 0 84336 47 36 11 36 0 8 0 mtagpl 96 599 0 341 11 3 8 9 0 8 0 mbufpl 256 189606 0 189167 511 474 37 156 0 8 1 bufpl 288 9692 0 3298 458 1 457 458 0 8 0 anonpl 24 909107 0 891318 187 69 118 135 0 188 2 amapchunkpl 152 88114 0 87442 70 38 32 41 0 158 2 amappl16 200 10156 0 9565 78 45 33 44 0 8 1 amappl15 192 38 0 37 1 0 1 1 0 8 0 amappl14 184 220 0 208 2 1 1 2 0 8 0 amappl13 176 7 0 7 2 2 0 1 0 8 0 amappl12 168 583 0 581 1 0 1 1 0 8 0 amappl11 160 44 0 33 1 0 1 1 0 8 0 amappl10 152 48 0 40 1 0 1 1 0 8 0 amappl9 144 972 0 971 1 0 1 1 0 8 0 amappl8 136 229 0 166 5 2 3 3 0 8 0 amappl7 128 179 0 156 2 0 2 2 0 8 0 amappl6 120 234 0 221 2 1 1 2 0 8 0 amappl5 112 231 0 223 1 0 1 1 0 8 0 amappl4 104 807 0 782 2 1 1 2 0 8 0 amappl3 96 12463 0 12419 2 0 2 2 0 8 0 amappl2 88 5070 0 5003 3 1 2 3 0 8 0 amappl1 80 103117 0 102467 32 15 17 26 0 8 0 amappl 88 28257 0 28101 5 0 5 5 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 72 131 0 1 3 0 3 3 0 8 0 uaddrrnd 24 4519 0 4496 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 4519 0 4496 1 0 1 1 0 8 0 vmmpekpl 168 40432 0 40385 3 0 3 3 0 8 0 vmmpepl 168 420323 0 417905 207 78 129 146 0 357 3 vmsppl 344 4518 0 4496 3 0 3 3 0 8 0 rwobjpl 24 115475 0 107780 49 1 48 49 0 8 0 pdppl 4096 9044 0 8992 296 232 64 66 0 8 12 pvpl 32 1796190 0 1773502 369 165 204 322 0 265 6 pmappl 216 4518 0 4496 2 0 2 2 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 1687 0 898 28 3 25 26 0 8 1 ddb> machine ddbcpu 0 No such command ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff82724846) at panic+0x161 sys/kern/subr_prf.c:198 __assert(ffffffff827a2ca7,ffffffff827c31cb,308,ffffffff826f47ef) at __assert+0x25 sys/kern/subr_prf.c:157 arptfree(fffffd807ca0c470) at arptfree+0x12d sys/netinet/if_ether.c:776 arptimer(ffffffff82c104b0) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82c104b0) at timeout_run+0x8b sys/kern/kern_timeout.c:641 softclock_thread(ffff8000ffffeae0) at softclock_thread+0xf4 sys/kern/kern_timeout.c:765 end trace frame: 0x0, count: -7 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff82724846) at panic+0x161 sys/kern/subr_prf.c:198 __assert(ffffffff827a2ca7,ffffffff827c31cb,308,ffffffff826f47ef) at __assert+0x25 sys/kern/subr_prf.c:157 arptfree(fffffd807ca0c470) at arptfree+0x12d sys/netinet/if_ether.c:776 arptimer(ffffffff82c104b0) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82c104b0) at timeout_run+0x8b sys/kern/kern_timeout.c:641 softclock_thread(ffff8000ffffeae0) at softclock_thread+0xf4 sys/kern/kern_timeout.c:765 end trace frame: 0x0, count: -7