panic: kernel diagnostic assertion "ifp != NULL" failed: file "/syzkaller/managers/main/kernel/sys/netinet/if_ether.c", line 716 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *266618 16543 0 0x14000 0x40000200 0 softclock db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic() at panic+0x15c sys/kern/subr_prf.c:207 __assert(ffffffff821e7905,ffffffff821ff642,2cc,ffffffff82170446) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd802df287e8) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff82500ec0) at arptimer+0x95 sys/netinet/if_ether.c:120 softclock_thread(ffff8000ffffec58) at softclock_thread+0x145 timeout_run sys/kern/kern_timeout.c:475 [inline] softclock_thread(ffff8000ffffec58) at softclock_thread+0x145 sys/kern/kern_timeout.c:552 end trace frame: 0x0, count: 9 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 kernel diagnostic assertion "ifp != NULL" failed: file "/syzkaller/managers/main/kernel/sys/netinet/if_ether.c", line 716 ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic() at panic+0x15c sys/kern/subr_prf.c:207 __assert(ffffffff821e7905,ffffffff821ff642,2cc,ffffffff82170446) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd802df287e8) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff82500ec0) at arptimer+0x95 sys/netinet/if_ether.c:120 softclock_thread(ffff8000ffffec58) at softclock_thread+0x145 timeout_run sys/kern/kern_timeout.c:475 [inline] softclock_thread(ffff8000ffffec58) at softclock_thread+0x145 sys/kern/kern_timeout.c:552 end trace frame: 0x0, count: -6 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff800014812bb0 rbx 0xffff800014812c60 rdx 0x2 rcx 0 rax 0 r8 0xffff800014812b70 r9 0x1 r10 0 r11 0x2c1ea7fc5a2ed934 r12 0x3000000008 r13 0xffff800014812bc0 r14 0x100 r15 0x1 rip 0xffffffff817df538 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800014812ba0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (softclock) pid=266618 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=51, nice=20 forw=0xffffffffffffffff, list=0xffff8000fffff3c0,0xffff8000ffffe778 process=0xffff8000ffffc6c0 user=0xffff80001480d000, vmspace=0xffffffff8256d628 estcpu=1, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 54294 122839 4944 0 3 0x3000 suspend syz-executor.1 54294 450345 4944 0 2 0x4081000 syz-executor.1 4944 114777 3235 0 3 0x82 wait syz-executor.1 77828 13320 0 0 3 0x14200 acct acct 52408 264011 3235 0 3 0x82 piperd syz-executor.0 24877 395025 0 0 3 0x14200 bored sosplice 3235 395829 32487 0 3 0x82 thrsleep syz-fuzzer 3235 93699 32487 0 3 0x4000082 thrsleep syz-fuzzer 3235 347582 32487 0 3 0x4000082 kqread syz-fuzzer 3235 113530 32487 0 3 0x4000082 thrsleep syz-fuzzer 3235 39360 32487 0 3 0x4000082 thrsleep syz-fuzzer 3235 391486 32487 0 3 0x4000082 thrsleep syz-fuzzer 3235 188768 32487 0 3 0x4000082 thrsleep syz-fuzzer 3235 147726 32487 0 3 0x4000082 thrsleep syz-fuzzer 32487 38794 51118 0 3 0x10008a pause ksh 51118 303168 27385 0 3 0x92 select sshd 32672 1167 1 0 3 0x100083 ttyin getty 27385 413069 1 0 3 0x80 select sshd 78327 456831 33742 73 3 0x100090 kqread syslogd 33742 103464 1 0 3 0x100082 netio syslogd 65150 379190 1 77 3 0x100090 poll dhclient 1501 13993 1 0 3 0x80 poll dhclient 65296 429274 0 0 2 0x14200 zerothread 90462 164226 0 0 3 0x14200 aiodoned aiodoned 75001 187042 0 0 3 0x14200 syncer update 80418 303687 0 0 3 0x14200 cleaner cleaner 32518 277385 0 0 3 0x14200 reaper reaper 75844 444209 0 0 3 0x14200 pgdaemon pagedaemon 83701 499065 0 0 3 0x14200 bored crynlk 31900 205264 0 0 3 0x14200 bored crypto 95332 81750 0 0 3 0x40014200 acpi0 acpi0 59502 79547 0 0 3 0x14200 bored softnet 62942 193074 0 0 3 0x14200 bored systqmp 60387 436546 0 0 3 0x14200 bored systq *16543 266618 0 0 7 0x40014200 softclock 50307 121117 0 0 3 0x40014200 idle0 99370 29887 0 0 3 0x14200 bored smr 1 271080 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 Kern Lim devbuf 9585 6372K 8171K 78643K 21357 0 0 pcb 13 11K 12K 78643K 1097 0 0 rtable 128 8K 9K 78643K 3061 0 0 ifaddr 89 20K 21K 78643K 848 0 0 counters 19 16K 16K 78643K 19 0 0 ioctlops 0 0K 2K 78643K 369 0 0 iov 0 0K 24K 78643K 2711 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1220 77K 77K 78643K 5341 0 0 UFS quota 1 32K 32K 78643K 1 0 0 UFS mount 5 36K 36K 78643K 5 0 0 shm 2 1K 9K 78643K 70 0 0 VM map 50 12K 12K 78643K 72 0 0 sem 12 0K 1K 78643K 2531 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1793 195K 288K 78643K 12645 0 0 file desc 5 13K 25K 78643K 4568 0 0 sigio 0 0K 0K 78643K 79 0 0 proc 50 38K 63K 78643K 1871 0 0 subproc 32 2K 2K 78643K 527 0 0 NFS srvsock 1 0K 0K 78643K 1 0 0 NFS daemon 1 16K 16K 78643K 1 0 0 ip_moptions 0 0K 0K 78643K 481 0 0 in_multi 31 2K 2K 78643K 525 0 0 ether_multi 1 0K 0K 78643K 36 0 0 mrt 0 0K 0K 78643K 27 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 180 795K 795K 78643K 180 0 0 exec 0 0K 1K 78643K 1076 0 0 pfkey data 0 0K 4K 78643K 2 0 0 pagedep 1 8K 8K 78643K 1 0 0 inodedep 1 32K 32K 78643K 1 0 0 newblk 1 0K 0K 78643K 1 0 0 VM swap 7 26K 26K 78643K 7 0 0 UVM amap 201 414K 414K 78643K 12575 0 0 UVM aobj 130 6K 6K 78643K 146 0 0 memdesc 1 4K 4K 78643K 1 0 0 crypto data 1 1K 1K 78643K 1 0 0 ip6_options 0 0K 1K 78643K 1014 0 0 NDP 20 0K 0K 78643K 271 0 0 temp 226 3540K 4180K 78643K 225700 0 0 kqueue 0 0K 0K 78643K 71 0 0 SYN cache 2 16K 16K 78643K 2 0 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 121 0 113 1 0 1 1 0 8 0 rtpcb 80 612 0 610 1 0 1 1 0 8 0 rtentry 112 580 0 532 2 0 2 2 0 8 0 unpcb 120 2455 0 2442 3 2 1 2 0 8 0 syncache 264 36 0 36 17 17 0 1 0 8 0 sackhl 24 1 0 1 1 1 0 1 0 8 0 tcpqe 32 100 0 100 10 10 0 1 0 8 0 tcpcb 544 1687 0 1683 6 5 1 2 0 8 0 ipq 40 28 0 28 14 14 0 1 0 8 0 ipqe 40 414 0 414 14 14 0 1 0 8 0 inpcb 280 7179 0 7169 43 42 1 13 0 8 0 rttmr 72 8 0 8 5 5 0 1 0 8 0 ip6q 72 4 0 3 3 2 1 1 0 8 0 ip6af 40 10 0 9 3 2 1 1 0 8 0 nd6 48 70 0 66 2 1 1 1 0 8 0 pkpcb 40 11 0 11 6 6 0 1 0 8 0 swfcl 56 6 0 0 1 0 1 1 0 8 0 ppxss 1128 109 0 109 22 22 0 1 0 8 0 art_heap8 4096 42 0 41 12 11 1 4 0 8 0 art_heap4 256 2557 0 2326 35 18 17 18 0 8 0 art_table 32 2599 0 2367 3 0 3 3 0 8 0 art_node 16 577 0 532 1 0 1 1 0 8 0 sysvmsgpl 40 18 0 14 1 0 1 1 0 8 0 semapl 112 2529 0 2519 1 0 1 1 0 8 0 shmpl 112 144 0 16 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 9236 0 7819 46 0 46 46 0 8 0 ffsino 240 9236 0 7819 86 2 84 84 0 8 0 nchpl 144 16574 0 16093 61 40 21 61 0 8 0 uvmvnodes 72 8476 0 0 155 0 155 155 0 8 0 vnodes 208 8476 0 0 447 0 447 447 0 8 0 namei 1024 58949 0 58949 4 4 0 1 0 8 0 vcpupl 1984 48 0 0 6 0 6 6 0 8 0 vmpool 520 70 0 22 5 1 4 4 0 8 0 scxspl 192 60490 0 60490 33 32 1 7 0 8 1 plimitpl 152 412 0 405 1 0 1 1 0 8 0 sigapl 432 4652 0 4639 2 0 2 2 0 8 0 futexpl 56 154128 0 154128 5 5 0 1 0 8 0 knotepl 112 1293 0 1274 2 1 1 2 0 8 0 kqueuepl 104 3012 0 3010 1 0 1 1 0 8 0 pipepl 112 4886 0 4867 12 11 1 2 0 8 0 fdescpl 424 4653 0 4639 2 0 2 2 0 8 0 filepl 120 45537 0 45432 37 33 4 11 0 8 0 lockfpl 104 2119 0 2118 1 0 1 1 0 8 0 lockfspl 48 597 0 596 1 0 1 1 0 8 0 sessionpl 112 46 0 36 1 0 1 1 0 8 0 pgrppl 48 92 0 82 1 0 1 1 0 8 0 ucredpl 96 6330 0 6322 1 0 1 1 0 8 0 zombiepl 144 4642 0 4641 1 0 1 1 0 8 0 processpl 864 4671 0 4641 4 0 4 4 0 8 0 procpl 632 10294 0 10256 5 1 4 5 0 8 0 sosppl 128 90 0 90 17 17 0 1 0 8 0 sockpl 384 10325 0 10303 73 70 3 22 0 8 0 mcl64k 65536 1739 0 1739 134 134 0 33 0 8 0 mcl16k 16384 101 0 101 18 18 0 1 0 8 0 mcl12k 12288 208 0 208 11 11 0 1 0 8 0 mcl9k 9216 89 0 89 17 17 0 1 0 8 0 mcl8k 8192 469 0 469 7 7 0 1 0 8 0 mcl4k 4096 470 0 470 8 8 0 1 0 8 0 mcl2k2 2112 37 0 37 13 13 0 1 0 8 0 mcl2k 2048 74759 0 74721 16 10 6 13 0 8 0 mtagpl 80 251 0 247 4 3 1 1 0 8 0 mbufpl 256 170896 0 170792 167 153 14 32 0 8 0 bufpl 256 27192 0 18712 532 1 531 531 0 8 0 anonpl 16 646451 0 625554 239 150 89 100 0 62 0 amapchunkpl 152 27092 0 26951 94 88 6 20 0 158 0 amappl16 192 31559 0 30126 275 203 72 72 0 8 0 amappl15 184 706 0 706 9 9 0 1 0 8 0 amappl14 176 564 0 558 1 0 1 1 0 8 0 amappl13 168 508 0 507 1 0 1 1 0 8 0 amappl12 160 1269 0 1264 1 0 1 1 0 8 0 amappl11 152 325 0 314 1 0 1 1 0 8 0 amappl10 144 332 0 330 1 0 1 1 0 8 0 amappl9 136 1410 0 1404 1 0 1 1 0 8 0 amappl8 128 897 0 860 2 0 2 2 0 8 0 amappl7 120 487 0 480 1 0 1 1 0 8 0 amappl6 112 301 0 288 1 0 1 1 0 8 0 amappl5 104 1732 0 1718 1 0 1 1 0 8 0 amappl4 96 4003 0 3972 1 0 1 1 0 8 0 amappl3 88 1747 0 1734 1 0 1 1 0 8 0 amappl2 80 35851 0 35769 3 1 2 3 0 8 0 amappl1 72 96038 0 95617 26 17 9 20 0 8 0 amappl 80 11065 0 10998 2 0 2 2 0 84 0 dma4096 4096 1 0 1 1 1 0 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 17 0 17 1 1 0 1 0 8 0 aobjpl 64 145 0 16 4 1 3 3 0 8 0 uaddrrnd 24 4723 0 4639 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 4723 0 4639 1 0 1 1 0 8 0 vmmpekpl 168 36335 0 36291 3 0 3 3 0 8 0 vmmpepl 168 580040 0 577316 432 297 135 151 0 357 16 vmsppl 272 4652 0 4639 4 3 1 2 0 8 0 pdppl 4096 9452 0 9370 13 2 11 11 0 8 0 pvpl 32 1703265 0 1679743 544 327 217 321 0 265 27 pmappl 200 4722 0 4661 4 0 4 4 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 1047 0 378 22 1 21 21 0 8 0