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 * 67421 3593 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(ffffffff821e45c9,ffffffff821ff294,2cc,ffffffff8216bb6e) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd802dfa0008) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff82556f88) at arptimer+0x95 sys/netinet/if_ether.c:120 softclock_thread(ffff8000ffffe9e0) at softclock_thread+0x145 timeout_run sys/kern/kern_timeout.c:475 [inline] softclock_thread(ffff8000ffffe9e0) 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(ffffffff821e45c9,ffffffff821ff294,2cc,ffffffff8216bb6e) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd802dfa0008) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff82556f88) at arptimer+0x95 sys/netinet/if_ether.c:120 softclock_thread(ffff8000ffffe9e0) at softclock_thread+0x145 timeout_run sys/kern/kern_timeout.c:475 [inline] softclock_thread(ffff8000ffffe9e0) at softclock_thread+0x145 sys/kern/kern_timeout.c:552 end trace frame: 0x0, count: -6 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff8000148128c0 rbx 0xffff800014812970 rdx 0x2 rcx 0 rax 0 r8 0xffff800014812880 r9 0x1 r10 0 r11 0x64f0980a4c0f9549 r12 0x3000000008 r13 0xffff8000148128d0 r14 0x100 r15 0x1 rip 0xffffffff815a86b8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000148128b0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (softclock) pid=67421 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=51, nice=20 forw=0xffffffffffffffff, list=0xffff8000ffffeed0,0xffff8000ffffe778 process=0xffff8000ffffcd80 user=0xffff80001480d000, vmspace=0xffffffff82591650 estcpu=1, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 1623 111247 43608 0 3 0x82 wait syz-executor.1 80510 173866 43608 0 2 0x2 syz-executor.0 63940 468021 1 0 3 0x100083 ttyin getty 13019 205177 0 0 3 0x14200 bored sosplice 43608 162068 84608 0 3 0x82 thrsleep syz-fuzzer 43608 271759 84608 0 2 0x4000482 syz-fuzzer 43608 99840 84608 0 3 0x4000082 thrsleep syz-fuzzer 43608 180128 84608 0 3 0x4000082 thrsleep syz-fuzzer 43608 467884 84608 0 3 0x4000082 thrsleep syz-fuzzer 43608 29182 84608 0 2 0x4000482 syz-fuzzer 43608 397185 84608 0 3 0x4000082 thrsleep syz-fuzzer 43608 233031 84608 0 3 0x4000082 kqread syz-fuzzer 84608 47390 29035 0 3 0x10008a pause ksh 29035 341664 84467 0 3 0x92 select sshd 84467 129492 1 0 3 0x80 select sshd 39629 158113 76868 73 2 0x100090 syslogd 76868 179398 1 0 3 0x100082 netio syslogd 77074 437025 1 77 3 0x100090 poll dhclient 97231 485360 1 0 3 0x80 poll dhclient 5405 272293 0 0 2 0x14200 zerothread 23141 308365 0 0 3 0x14200 aiodoned aiodoned 1970 64513 0 0 2 0x14200 update 1024 516850 0 0 3 0x14200 cleaner cleaner 79254 242300 0 0 2 0x14200 reaper 46282 34203 0 0 3 0x14200 pgdaemon pagedaemon 67153 375172 0 0 3 0x14200 bored crynlk 57322 244369 0 0 3 0x14200 bored crypto 26067 477959 0 0 3 0x40014200 acpi0 acpi0 22192 226396 0 0 2 0x14200 softnet 46632 378461 0 0 2 0x14200 systqmp 16812 153223 0 0 2 0x14200 systq * 3593 67421 0 0 7 0x40014200 softclock 99156 457504 0 0 3 0x40014200 idle0 23555 10928 0 0 3 0x14200 bored smr 1 152866 0 0 3 0x82 wait init 0 0 -1 0 2 0x10200 swapper ddb> show all locks No such command ddb> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9582 7021K 7908K 78643K 26957 0 0 pcb 13 10K 12K 78643K 848 0 0 rtable 102 12K 13K 78643K 2286 0 0 ifaddr 90 20K 23K 78643K 608 0 0 counters 19 16K 16K 78643K 19 0 0 ioctlops 0 0K 2K 78643K 210 0 0 iov 0 0K 24K 78643K 2404 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1210 76K 77K 78643K 6103 0 0 UFS quota 1 32K 32K 78643K 1 0 0 UFS mount 5 36K 36K 78643K 5 0 0 shm 2 1K 5K 78643K 60 0 0 VM map 20 5K 5K 78643K 36 0 0 sem 12 0K 0K 78643K 879 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1793 195K 288K 78643K 12645 0 0 file desc 4 9K 25K 78643K 4426 0 0 sigio 0 0K 0K 78643K 409 0 0 proc 49 38K 62K 78643K 1388 0 0 subproc 32 2K 2K 78643K 323 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 453 0 0 in_multi 14 0K 2K 78643K 451 0 0 ether_multi 1 0K 0K 78643K 36 0 0 mrt 0 0K 0K 78643K 17 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 84 371K 371K 78643K 84 0 0 exec 0 0K 1K 78643K 756 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 135 185K 201K 78643K 11541 0 0 UVM aobj 130 4K 4K 78643K 141 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 854 0 0 NDP 21 0K 1K 78643K 203 0 0 temp 234 3545K 4185K 78643K 338846 0 0 kqueue 0 0K 0K 78643K 35 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 83 0 79 1 0 1 1 0 8 0 rtpcb 80 2623 0 2621 1 0 1 1 0 8 0 rtentry 112 412 0 380 2 0 2 2 0 8 0 unpcb 120 3837 0 3825 2 1 1 2 0 8 0 syncache 264 21 0 21 8 8 0 1 0 8 0 tcpqe 32 21 0 21 7 7 0 1 0 8 0 tcpcb 544 1760 0 1756 24 23 1 13 0 8 0 ipq 40 28 0 28 10 10 0 1 0 8 0 ipqe 40 665 0 665 10 10 0 1 0 8 0 inpcb 280 6363 0 6356 24 23 1 9 0 8 0 rttmr 72 8 0 7 1 0 1 1 0 8 0 ip6q 72 2 0 2 1 1 0 1 0 8 0 ip6af 40 6 0 6 1 1 0 1 0 8 0 nd6 48 55 0 55 1 1 0 1 0 8 0 pkpcb 40 8 0 8 3 3 0 1 0 8 0 swfcl 56 4 0 0 1 0 1 1 0 8 0 ppxss 1128 63 0 63 13 13 0 1 0 8 0 art_heap8 4096 13 0 12 10 9 1 3 0 8 0 art_heap4 256 1966 0 1798 31 16 15 18 0 8 0 art_table 32 1979 0 1810 3 0 3 3 0 8 0 art_node 16 411 0 382 1 0 1 1 0 8 0 sysvmsgpl 40 80 0 56 1 0 1 1 0 8 0 semapl 112 877 0 867 1 0 1 1 0 8 0 shmpl 112 139 0 11 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 8896 0 7341 51 0 51 51 0 8 0 ffsino 240 8896 0 7341 92 0 92 92 0 8 0 nchpl 144 17595 0 17110 60 41 19 60 0 8 0 uvmvnodes 72 6344 0 0 116 0 116 116 0 8 0 vnodes 208 6344 0 0 334 0 334 334 0 8 0 namei 1024 65250 0 65249 4 3 1 1 0 8 0 vcpupl 1984 18 0 0 3 0 3 3 0 8 0 vmpool 520 34 0 16 3 1 2 2 0 8 0 scsiplug 64 2 0 2 2 2 0 1 0 8 0 scxspl 192 56081 0 56081 27 26 1 7 0 8 1 plimitpl 152 325 0 318 1 0 1 1 0 8 0 sigapl 432 4547 0 4535 2 0 2 2 0 8 0 futexpl 56 137047 0 137047 6 6 0 1 0 8 0 knotepl 112 998 0 979 3 2 1 3 0 8 0 kqueuepl 104 3989 0 3987 4 3 1 4 0 8 0 pipepl 112 2268 0 2249 9 8 1 2 0 8 0 fdescpl 424 4548 0 4535 2 0 2 2 0 8 0 filepl 120 49091 0 48996 25 21 4 11 0 8 1 lockfpl 104 1363 0 1362 1 0 1 1 0 8 0 lockfspl 48 442 0 441 1 0 1 1 0 8 0 sessionpl 112 35 0 25 1 0 1 1 0 8 0 pgrppl 48 85 0 75 1 0 1 1 0 8 0 ucredpl 96 4786 0 4777 1 0 1 1 0 8 0 zombiepl 144 4540 0 4539 4 3 1 1 0 8 0 processpl 864 4568 0 4539 4 0 4 4 0 8 0 procpl 632 9726 0 9690 5 1 4 5 0 8 0 sosppl 128 50 0 50 12 12 0 1 0 8 0 sockpl 384 12868 0 12847 42 39 3 14 0 8 0 mcl64k 65536 848 0 848 68 68 0 32 0 8 0 mcl16k 16384 56 0 56 14 14 0 1 0 8 0 mcl12k 12288 99 0 99 12 12 0 1 0 8 0 mcl9k 9216 83 0 83 15 15 0 1 0 8 0 mcl8k 8192 945 0 945 7 7 0 1 0 8 0 mcl4k 4096 431 0 431 5 5 0 1 0 8 0 mcl2k2 2112 36 0 36 14 14 0 1 0 8 0 mcl2k 2048 75587 0 75532 19 12 7 14 0 8 0 mtagpl 80 156 0 156 2 2 0 1 0 8 0 mbufpl 256 159848 0 159761 131 120 11 58 0 8 0 bufpl 256 27911 0 21566 397 0 397 397 0 8 0 anonpl 16 499839 0 481334 204 114 90 101 0 62 12 amapchunkpl 152 22539 0 22431 67 61 6 15 0 158 0 amappl16 192 25383 0 24281 185 121 64 68 0 8 8 amappl15 184 487 0 487 3 3 0 1 0 8 0 amappl14 176 1357 0 1355 1 0 1 1 0 8 0 amappl13 168 344 0 342 1 0 1 1 0 8 0 amappl12 160 1373 0 1372 2 1 1 1 0 8 0 amappl11 152 590 0 576 1 0 1 1 0 8 0 amappl10 144 161 0 160 1 0 1 1 0 8 0 amappl9 136 1124 0 1116 1 0 1 1 0 8 0 amappl8 128 693 0 650 2 0 2 2 0 8 0 amappl7 120 247 0 242 1 0 1 1 0 8 0 amappl6 112 568 0 553 1 0 1 1 0 8 0 amappl5 104 1653 0 1643 1 0 1 1 0 8 0 amappl4 96 4916 0 4890 1 0 1 1 0 8 0 amappl3 88 1686 0 1681 1 0 1 1 0 8 0 amappl2 80 35546 0 35475 3 1 2 3 0 8 0 amappl1 72 86880 0 86471 27 18 9 20 0 8 0 amappl 80 10263 0 10215 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 64 140 0 11 3 0 3 3 0 8 0 uaddrrnd 24 4582 0 4535 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 4582 0 4535 1 0 1 1 0 8 0 vmmpekpl 168 31739 0 31711 2 0 2 2 0 8 0 vmmpepl 168 542993 0 540817 318 201 117 156 0 357 14 vmsppl 272 4547 0 4534 4 3 1 2 0 8 0 pdppl 4096 9170 0 9118 12 5 7 8 0 8 0 pvpl 32 1265673 0 1244462 393 180 213 237 0 265 33 pmappl 200 4581 0 4550 2 0 2 2 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 823 0 287 17 1 16 17 0 8 0