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 *429151 2010 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(ffffffff821e60c6,ffffffff821fd48f,2cc,ffffffff8216e00a) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd803c0148c8) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff825225e0) at arptimer+0x95 sys/netinet/if_ether.c:120 softclock_thread(ffff8000ffffeed0) at softclock_thread+0x145 timeout_run sys/kern/kern_timeout.c:475 [inline] softclock_thread(ffff8000ffffeed0) 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(ffffffff821e60c6,ffffffff821fd48f,2cc,ffffffff8216e00a) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd803c0148c8) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff825225e0) at arptimer+0x95 sys/netinet/if_ether.c:120 softclock_thread(ffff8000ffffeed0) at softclock_thread+0x145 timeout_run sys/kern/kern_timeout.c:475 [inline] softclock_thread(ffff8000ffffeed0) at softclock_thread+0x145 sys/kern/kern_timeout.c:552 end trace frame: 0x0, count: -6 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff800014812960 rbx 0xffff800014812a10 rdx 0x2 rcx 0 rax 0 r8 0xffff800014812920 r9 0x1 r10 0 r11 0xb714bd011ac4299a r12 0x3000000008 r13 0xffff800014812970 r14 0x100 r15 0x1 rip 0xffffffff811e4308 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800014812950 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (softclock) pid=429151 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff8000fffff148,0xffff8000ffffec68 process=0xffff8000ffffc360 user=0xffff80001480d000, vmspace=0xffffffff825a72b8 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 32906 303791 15301 0 2 0x480 syz-executor.1 32906 341933 15301 0 3 0x4000080 rest syz-executor.1 32906 465988 15301 0 3 0x4000080 fsleep syz-executor.1 78382 139061 49947 0 3 0x82 piperd syz-executor.0 15301 440736 49947 0 2 0x482 syz-executor.1 61642 179300 0 0 3 0x14200 acct acct 23301 187997 0 0 3 0x14200 bored sosplice 49947 475010 44323 0 3 0x82 thrsleep syz-fuzzer 49947 345073 44323 0 3 0x4000082 thrsleep syz-fuzzer 49947 486016 44323 0 3 0x4000082 kqread syz-fuzzer 49947 73433 44323 0 3 0x4000082 thrsleep syz-fuzzer 49947 327231 44323 0 3 0x4000082 thrsleep syz-fuzzer 49947 372503 44323 0 3 0x4000082 thrsleep syz-fuzzer 49947 62468 44323 0 3 0x4000082 thrsleep syz-fuzzer 44323 330491 44696 0 3 0x10008a pause ksh 44696 416923 77214 0 3 0x92 select sshd 54091 420218 1 0 3 0x100083 ttyin getty 77214 412463 1 0 3 0x80 select sshd 69006 54751 74394 73 3 0x100090 kqread syslogd 74394 369723 1 0 3 0x100082 netio syslogd 24226 283609 1 77 3 0x100090 poll dhclient 91735 343801 1 0 3 0x80 poll dhclient 41293 96808 0 0 3 0x14200 pgzero zerothread 70997 108766 0 0 3 0x14200 aiodoned aiodoned 97488 133029 0 0 3 0x14200 syncer update 81768 424744 0 0 3 0x14200 cleaner cleaner 19578 248863 0 0 3 0x14200 reaper reaper 35201 493351 0 0 3 0x14200 pgdaemon pagedaemon 88377 91932 0 0 3 0x14200 bored crynlk 63460 239323 0 0 3 0x14200 bored crypto 47322 67517 0 0 3 0x40014200 acpi0 acpi0 36513 450552 0 0 3 0x14200 bored softnet 42275 136687 0 0 3 0x14200 bored systqmp 35559 301849 0 0 3 0x14200 bored systq * 2010 429151 0 0 7 0x40014200 softclock 45044 160887 0 0 3 0x40014200 idle0 54639 289247 0 0 3 0x14200 bored smr 1 519018 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 9642 7055K 8070K 78643K 33853 0 0 pcb 13 11K 12K 78643K 1371 0 0 rtable 116 8K 9K 78643K 3905 0 0 ifaddr 112 23K 24K 78643K 940 0 0 counters 19 16K 16K 78643K 19 0 0 ioctlops 0 0K 2K 78643K 430 0 0 iov 0 0K 32K 78643K 1880 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1251 79K 79K 78643K 9126 0 0 UFS quota 1 32K 32K 78643K 1 0 0 UFS mount 5 36K 36K 78643K 5 0 0 shm 3 5K 9K 78643K 104 0 0 VM map 57 14K 14K 78643K 68 0 0 sem 12 0K 1K 78643K 1410 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1793 195K 288K 78643K 12645 0 0 file desc 5 13K 25K 78643K 6227 0 0 sigio 0 0K 0K 78643K 101 0 0 proc 50 38K 55K 78643K 2153 0 0 subproc 32 2K 2K 78643K 558 0 0 NFS srvsock 1 0K 0K 78643K 1 0 0 NFS daemon 1 16K 16K 78643K 1 0 0 ip_moptions 0 0K 1K 78643K 2671 0 0 in_multi 34 2K 2K 78643K 689 0 0 ether_multi 1 0K 0K 78643K 53 0 0 mrt 0 0K 0K 78643K 39 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 174 768K 768K 78643K 174 0 0 exec 0 0K 1K 78643K 1458 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 190 478K 482K 78643K 17986 0 0 UVM aobj 130 6K 6K 78643K 139 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 1339 0 0 NDP 27 0K 1K 78643K 314 0 0 temp 275 3546K 4184K 78643K 219445 0 0 kqueue 0 0K 0K 78643K 49 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 64 162 0 155 1 0 1 1 0 8 0 rtpcb 80 812 0 810 1 0 1 1 0 8 0 rtentry 112 761 0 719 2 0 2 2 0 8 0 unpcb 120 6970 0 6958 21 20 1 2 0 8 0 syncache 264 37 0 37 15 15 0 1 0 8 0 sackhl 24 3 0 3 3 3 0 1 0 8 0 tcpqe 32 203 0 203 7 7 0 1 0 8 0 tcpcb 544 2767 0 2763 35 34 1 15 0 8 0 ipq 40 59 0 59 20 20 0 1 0 8 0 ipqe 40 1385 0 1385 20 20 0 1 0 8 0 inpcb 280 8565 0 8557 43 41 2 9 0 8 1 rttmr 72 10 0 10 8 8 0 1 0 8 0 ip6q 72 1 0 1 1 1 0 1 0 8 0 ip6af 40 3 0 3 1 1 0 1 0 8 0 nd6 48 87 0 84 6 5 1 1 0 8 0 pkpcb 40 64 0 64 17 16 1 1 0 8 1 swfcl 56 6 0 0 1 0 1 1 0 8 0 ppxss 1128 89 0 89 26 25 1 1 0 8 1 art_heap8 4096 33 0 32 18 17 1 3 0 8 0 art_heap4 256 3103 0 2890 46 31 15 16 0 8 0 art_table 32 3136 0 2922 2 0 2 2 0 8 0 art_node 16 760 0 721 1 0 1 1 0 8 0 sysvmsgpl 40 322 0 289 1 0 1 1 0 8 0 semupl 112 2 0 2 1 1 0 1 0 8 0 semapl 112 1404 0 1394 1 0 1 1 0 8 0 shmpl 112 137 0 9 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 13153 0 11743 46 0 46 46 0 8 0 ffsino 240 13153 0 11743 84 0 84 84 0 8 0 nchpl 144 23799 0 23271 61 41 20 60 0 8 0 uvmvnodes 72 8322 0 0 152 0 152 152 0 8 0 vnodes 208 8322 0 0 438 0 438 438 0 8 0 namei 1024 85535 0 85535 4 3 1 1 0 8 1 vcpupl 1984 55 0 0 7 0 7 7 0 8 0 vmpool 520 66 0 11 4 0 4 4 0 8 0 scsiplug 64 6 0 6 5 5 0 1 0 8 0 scxspl 192 94232 0 94232 29 28 1 7 0 8 1 plimitpl 152 496 0 489 1 0 1 1 0 8 0 sigapl 432 6308 0 6295 2 0 2 2 0 8 0 futexpl 56 219479 0 219478 4 3 1 1 0 8 0 knotepl 112 1598 0 1579 4 3 1 2 0 8 0 kqueuepl 104 1988 0 1985 7 6 1 4 0 8 0 pipepl 112 7688 0 7667 25 23 2 3 0 8 1 fdescpl 424 6309 0 6295 2 0 2 2 0 8 0 filepl 120 68423 0 68317 67 62 5 11 0 8 1 lockfpl 104 12492 0 12489 1 0 1 1 0 8 0 lockfspl 48 3128 0 3125 1 0 1 1 0 8 0 sessionpl 112 47 0 37 1 0 1 1 0 8 0 pgrppl 48 2046 0 2036 1 0 1 1 0 8 0 ucredpl 96 6860 0 6853 1 0 1 1 0 8 0 zombiepl 144 6297 0 6297 1 0 1 1 0 8 1 processpl 864 6327 0 6297 4 0 4 4 0 8 0 procpl 632 15528 0 15490 5 1 4 5 0 8 0 sosppl 128 69 0 69 16 16 0 1 0 8 0 sockpl 384 16498 0 16476 84 79 5 14 0 8 2 mcl64k 65536 1235 0 1235 102 101 1 33 0 8 1 mcl16k 16384 118 0 118 21 20 1 1 0 8 1 mcl12k 12288 212 0 212 10 9 1 1 0 8 1 mcl9k 9216 81 0 81 21 21 0 1 0 8 0 mcl8k 8192 566 0 566 5 4 1 1 0 8 1 mcl4k 4096 1180 0 1180 6 5 1 1 0 8 1 mcl2k2 2112 99 0 99 20 20 0 1 0 8 0 mcl2k 2048 82336 0 82290 18 11 7 16 0 8 1 mtagpl 80 336 0 320 7 6 1 2 0 8 0 mbufpl 256 196486 0 196317 172 152 20 49 0 8 3 bufpl 256 34226 0 25866 530 7 523 523 0 8 0 anonpl 16 855749 0 836781 276 183 93 95 0 62 12 amapchunkpl 152 37700 0 37583 145 136 9 19 0 158 3 amappl16 192 38939 0 37831 306 242 64 70 0 8 8 amappl15 184 2274 0 2274 7 7 0 1 0 8 0 amappl14 176 493 0 487 1 0 1 1 0 8 0 amappl13 168 1299 0 1299 4 4 0 1 0 8 0 amappl12 160 511 0 507 1 0 1 1 0 8 0 amappl11 152 838 0 826 1 0 1 1 0 8 0 amappl10 144 910 0 909 1 0 1 1 0 8 0 amappl9 136 1746 0 1739 1 0 1 1 0 8 0 amappl8 128 1282 0 1236 3 1 2 2 0 8 0 amappl7 120 1042 0 1035 1 0 1 1 0 8 0 amappl6 112 811 0 801 1 0 1 1 0 8 0 amappl5 104 963 0 951 1 0 1 1 0 8 0 amappl4 96 7051 0 7022 1 0 1 1 0 8 0 amappl3 88 1295 0 1287 1 0 1 1 0 8 0 amappl2 80 49636 0 49568 3 1 2 3 0 8 0 amappl1 72 130825 0 130407 27 18 9 20 0 8 0 amappl 80 16333 0 16262 3 1 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 64 138 0 9 3 0 3 3 0 8 0 uaddrrnd 24 6375 0 6295 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 6375 0 6295 1 0 1 1 0 8 0 vmmpekpl 168 50709 0 50665 4 1 3 3 0 8 0 vmmpepl 168 779285 0 776958 420 281 139 143 0 357 30 vmsppl 272 6308 0 6295 3 2 1 2 0 8 0 pdppl 4096 12756 0 12667 17 5 12 12 0 8 0 pvpl 32 2218260 0 2196663 639 357 282 307 0 265 102 pmappl 200 6374 0 6306 4 0 4 4 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 1066 0 394 22 2 20 21 0 8 0