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 * 21674 61533 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(ffffffff821e5c23,ffffffff821ff74c,2cc,ffffffff8216f81c) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd803cd6b938) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff825008e8) at arptimer+0x95 sys/netinet/if_ether.c:120 softclock_thread(ffff8000fffff148) at softclock_thread+0x145 timeout_run sys/kern/kern_timeout.c:475 [inline] softclock_thread(ffff8000fffff148) 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(ffffffff821e5c23,ffffffff821ff74c,2cc,ffffffff8216f81c) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd803cd6b938) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff825008e8) at arptimer+0x95 sys/netinet/if_ether.c:120 softclock_thread(ffff8000fffff148) at softclock_thread+0x145 timeout_run sys/kern/kern_timeout.c:475 [inline] softclock_thread(ffff8000fffff148) at softclock_thread+0x145 sys/kern/kern_timeout.c:552 end trace frame: 0x0, count: -6 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff800014812370 rbx 0xffff800014812420 rdx 0x2 rcx 0 rax 0 r8 0xffff800014812330 r9 0x1 r10 0 r11 0x841d2fcccb7d5992 r12 0x3000000008 r13 0xffff800014812380 r14 0x100 r15 0x1 rip 0xffffffff81a536b8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800014812360 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (softclock) pid=21674 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff8000fffff3c0,0xffff8000ffffec68 process=0xffff8000ffffc000 user=0xffff80001480d000, vmspace=0xffffffff8257e590 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 5881 318983 42027 0 3 0x3000 suspend syz-executor.1 5881 191580 42027 0 2 0x4081000 syz-executor.1 33421 193446 70057 0 3 0x82 piperd syz-executor.0 42027 524199 70057 0 3 0x82 wait syz-executor.1 29843 284435 0 0 3 0x14200 acct acct 88851 370672 1 0 3 0x100083 ttyin getty 41171 225341 0 0 3 0x14200 bored sosplice 70057 297195 13848 0 3 0x82 thrsleep syz-fuzzer 70057 359280 13848 0 3 0x4000082 thrsleep syz-fuzzer 70057 137728 13848 0 3 0x4000082 kqread syz-fuzzer 70057 18806 13848 0 3 0x4000082 thrsleep syz-fuzzer 70057 376057 13848 0 3 0x4000082 thrsleep syz-fuzzer 70057 422751 13848 0 3 0x4000082 thrsleep syz-fuzzer 70057 310651 13848 0 3 0x4000082 thrsleep syz-fuzzer 70057 186420 13848 0 3 0x4000082 thrsleep syz-fuzzer 13848 10882 25535 0 3 0x10008a pause ksh 25535 193204 28995 0 3 0x92 select sshd 28995 213987 1 0 3 0x80 select sshd 83764 30118 89862 73 3 0x100090 kqread syslogd 89862 127582 1 0 3 0x100082 netio syslogd 7501 416268 0 0 2 0x14200 zerothread 88604 279334 0 0 3 0x14200 aiodoned aiodoned 95381 81878 0 0 2 0x14200 update 20990 199183 0 0 3 0x14200 cleaner cleaner 13319 301779 0 0 3 0x14200 reaper reaper 39626 41800 0 0 3 0x14200 pgdaemon pagedaemon 76963 479030 0 0 3 0x14200 bored crynlk 99387 19247 0 0 3 0x14200 bored crypto 86110 319250 0 0 3 0x40014200 acpi0 acpi0 63467 384879 0 0 3 0x14200 bored softnet 36786 117101 0 0 2 0x14200 systqmp 90765 370144 0 0 3 0x14200 bored systq *61533 21674 0 0 7 0x40014200 softclock 31761 193105 0 0 3 0x40014200 idle0 74424 141458 0 0 3 0x14200 bored smr 1 459116 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 9600 6327K 9794K 78643K 88116 0 0 pcb 13 14K 15K 78643K 3333 0 0 rtable 172 15K 16K 78643K 4638 0 0 ifaddr 133 34K 34K 78643K 2135 0 0 counters 19 16K 16K 78643K 19 0 0 ioctlops 0 0K 2K 78643K 824 0 0 iov 0 0K 32K 78643K 3523 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1236 78K 78K 78643K 24308 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 284 0 0 VM map 142 35K 35K 78643K 182 0 0 sem 12 0K 0K 78643K 5388 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1793 195K 288K 78643K 12645 0 0 file desc 5 13K 25K 78643K 13724 0 0 sigio 0 0K 0K 78643K 644 0 0 proc 45 30K 55K 78643K 5032 0 0 subproc 32 2K 2K 78643K 1491 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 1227 0 0 in_multi 54 3K 3K 78643K 1464 0 0 ether_multi 1 0K 0K 78643K 134 0 0 mrt 2 0K 0K 78643K 98 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 120 530K 530K 78643K 120 0 0 exec 0 0K 1K 78643K 2787 0 0 pfkey data 0 0K 4K 78643K 4 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 342 1037K 1038K 78643K 36294 0 0 UVM aobj 130 4K 4K 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 3216 0 0 NDP 23 0K 1K 78643K 686 0 0 temp 247 3545K 4185K 78643K 355026 0 0 kqueue 0 0K 0K 78643K 216 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 64 278 0 272 1 0 1 1 0 8 0 rtpcb 80 1254 0 1254 32 31 1 1 0 8 1 rtentry 112 1408 0 1340 2 0 2 2 0 8 0 unpcb 120 8408 0 8389 26 25 1 2 0 8 0 syncache 264 93 0 93 43 43 0 1 0 8 0 sackhl 24 3 0 3 3 3 0 1 0 8 0 tcpqe 32 161 0 161 23 23 0 1 0 8 0 tcpcb 544 7070 0 7066 68 67 1 15 0 8 0 ipq 40 130 0 130 57 57 0 1 0 8 0 ipqe 40 3825 0 3825 57 57 0 1 0 8 0 inpcb 280 23669 0 23663 129 128 1 13 0 8 0 rttmr 72 35 0 34 5 4 1 1 0 8 0 ip6q 72 6 0 6 6 6 0 1 0 8 0 ip6af 40 16 0 16 6 6 0 1 0 8 0 nd6 48 191 0 188 12 11 1 1 0 8 0 pkpcb 40 77 0 77 24 24 0 1 0 8 0 swfcl 56 14 0 0 1 0 1 1 0 8 0 ppxss 1128 287 0 287 64 64 0 1 0 8 0 art_heap8 4096 26 0 18 17 9 8 8 0 8 0 art_heap4 256 5962 0 5647 91 71 20 22 0 8 0 art_table 32 5988 0 5665 4 1 3 3 0 8 0 art_node 16 1402 0 1347 1 0 1 1 0 8 0 sysvmsgpl 40 60 0 42 1 0 1 1 0 8 0 semapl 112 5386 0 5376 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 23093 0 21632 49 1 48 48 0 8 0 ffsino 240 23093 0 21632 89 2 87 87 0 8 0 nchpl 144 44005 0 43502 60 40 20 60 0 8 0 uvmvnodes 72 9828 0 0 179 0 179 179 0 8 0 vnodes 208 9828 0 0 518 0 518 518 0 8 0 namei 1024 175186 0 175186 13 12 1 1 0 8 1 vcpupl 1984 140 0 0 18 0 18 18 0 8 0 vmpool 520 180 0 40 11 1 10 10 0 8 0 scsiplug 64 24 0 24 13 13 0 1 0 8 0 scxspl 192 164869 0 164869 91 90 1 7 0 8 1 plimitpl 152 1266 0 1258 1 0 1 1 0 8 0 sigapl 432 13640 0 13629 2 0 2 2 0 8 0 futexpl 56 416310 0 416310 15 14 1 1 0 8 1 knotepl 112 3426 0 3407 6 5 1 2 0 8 0 kqueuepl 104 5038 0 5036 13 12 1 4 0 8 0 pipepl 112 10924 0 10905 26 24 2 2 0 8 1 fdescpl 424 13641 0 13629 2 0 2 2 0 8 0 filepl 120 139804 0 139715 91 87 4 11 0 8 0 lockfpl 104 5184 0 5184 15 15 0 1 0 8 0 lockfspl 48 1712 0 1712 15 15 0 1 0 8 0 sessionpl 112 103 0 95 1 0 1 1 0 8 0 pgrppl 48 366 0 358 1 0 1 1 0 8 0 ucredpl 96 25280 0 25274 1 0 1 1 0 8 0 zombiepl 144 13634 0 13633 1 0 1 1 0 8 0 processpl 864 13661 0 13633 4 0 4 4 0 8 0 procpl 632 30866 0 30830 5 1 4 5 0 8 0 sosppl 128 228 0 228 58 58 0 1 0 8 0 sockpl 384 33785 0 33760 185 181 4 21 0 8 0 mcl64k 65536 4624 0 4624 403 403 0 64 0 8 0 mcl16k 16384 203 0 203 62 62 0 1 0 8 0 mcl12k 12288 470 0 470 41 41 0 1 0 8 0 mcl9k 9216 264 0 264 59 59 0 1 0 8 0 mcl8k 8192 687 0 687 32 32 0 1 0 8 0 mcl4k 4096 1712 0 1712 17 17 0 1 0 8 0 mcl2k2 2112 110 0 110 48 48 0 1 0 8 0 mcl2k 2048 99352 0 99305 24 17 7 14 0 8 0 mtagpl 80 642 0 622 15 14 1 1 0 8 0 mbufpl 256 280007 0 279848 701 687 14 37 0 8 3 bufpl 256 60347 0 50523 618 3 615 615 0 8 0 anonpl 16 1796568 0 1770764 390 286 104 113 0 62 0 amapchunkpl 152 77098 0 76946 253 244 9 22 0 158 0 amappl16 192 87533 0 85876 582 499 83 84 0 8 0 amappl15 184 3698 0 3698 15 15 0 1 0 8 0 amappl14 176 2194 0 2187 1 0 1 1 0 8 0 amappl13 168 989 0 989 8 8 0 1 0 8 0 amappl12 160 2401 0 2399 2 1 1 1 0 8 0 amappl11 152 1250 0 1246 1 0 1 1 0 8 0 amappl10 144 2086 0 2082 1 0 1 1 0 8 0 amappl9 136 3271 0 3266 1 0 1 1 0 8 0 amappl8 128 2883 0 2792 6 2 4 4 0 8 0 amappl7 120 2436 0 2428 1 0 1 1 0 8 0 amappl6 112 1095 0 1074 1 0 1 1 0 8 0 amappl5 104 3278 0 3271 1 0 1 1 0 8 0 amappl4 96 13468 0 13441 1 0 1 1 0 8 0 amappl3 88 2939 0 2916 1 0 1 1 0 8 0 amappl2 80 105812 0 105741 3 1 2 3 0 8 0 amappl1 72 263128 0 262740 27 18 9 20 0 8 0 amappl 80 32690 0 32582 3 0 3 3 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 13821 0 13629 2 0 2 2 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 13821 0 13629 2 0 2 2 0 8 0 vmmpekpl 168 86899 0 86852 3 0 3 3 0 8 0 vmmpepl 168 1691716 0 1688577 1034 861 173 180 0 357 36 vmsppl 272 13640 0 13629 4 3 1 2 0 8 0 pdppl 4096 27648 0 27478 32 10 22 22 0 8 0 pvpl 32 4829065 0 4803053 1195 970 225 339 0 265 15 pmappl 200 13820 0 13669 10 1 9 9 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 2176 0 1397 24 1 23 23 0 8 0