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 *377912 89844 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(ffffffff821e6d2f,ffffffff82202a57,2cc,ffffffff8216f65a) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd803002be08) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff82558270) at arptimer+0x95 sys/netinet/if_ether.c:120 softclock_thread(ffff8000ffffe000) at softclock_thread+0x145 timeout_run sys/kern/kern_timeout.c:475 [inline] softclock_thread(ffff8000ffffe000) 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(ffffffff821e6d2f,ffffffff82202a57,2cc,ffffffff8216f65a) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd803002be08) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff82558270) at arptimer+0x95 sys/netinet/if_ether.c:120 softclock_thread(ffff8000ffffe000) at softclock_thread+0x145 timeout_run sys/kern/kern_timeout.c:475 [inline] softclock_thread(ffff8000ffffe000) at softclock_thread+0x145 sys/kern/kern_timeout.c:552 end trace frame: 0x0, count: -6 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff800014812400 rbx 0xffff8000148124b0 rdx 0x2 rcx 0 rax 0 r8 0xffff8000148123c0 r9 0x1 r10 0 r11 0x13b3f95722a845b9 r12 0x3000000008 r13 0xffff800014812410 r14 0x100 r15 0x1 rip 0xffffffff820a1928 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000148123f0 ss 0 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (softclock) pid=377912 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=51, nice=20 forw=0xffffffffffffffff, list=0xffff8000ffffe278,0xffff8000ffffe500 process=0xffff8000ffffc000 user=0xffff80001480d000, vmspace=0xffffffff8259ece0 estcpu=1, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 73069 416497 26815 0 2 0 syz-executor.0 26815 164212 61596 0 2 0x482 syz-executor.0 89143 480387 61596 0 2 0x482 syz-executor.1 14859 374589 0 0 3 0x14200 acct acct 20370 3046 0 0 3 0x14200 bored sosplice 61596 466145 366 0 3 0x82 thrsleep syz-fuzzer 61596 327946 366 0 2 0x4000482 syz-fuzzer 61596 317527 366 0 3 0x4000082 thrsleep syz-fuzzer 61596 296146 366 0 3 0x4000082 thrsleep syz-fuzzer 61596 490633 366 0 3 0x4000082 thrsleep syz-fuzzer 61596 128996 366 0 3 0x4000082 kqread syz-fuzzer 61596 137314 366 0 3 0x4000082 thrsleep syz-fuzzer 366 428692 56984 0 3 0x10008a pause ksh 56984 186252 86108 0 3 0x92 select sshd 39042 69794 1 0 3 0x100083 ttyopn getty 86108 20477 1 0 3 0x80 select sshd 73005 444149 81762 73 3 0x100090 kqread syslogd 81762 237082 1 0 3 0x100082 netio syslogd 24907 240146 1 77 3 0x100090 poll dhclient 29296 133205 1 0 3 0x80 poll dhclient 30504 453035 0 0 2 0x14200 zerothread 77447 12775 0 0 3 0x14200 aiodoned aiodoned 53668 172104 0 0 3 0x14200 syncer update 14001 92109 0 0 3 0x14200 cleaner cleaner 15229 282089 0 0 3 0x14200 reaper reaper 73025 52594 0 0 3 0x14200 pgdaemon pagedaemon 15519 431600 0 0 3 0x14200 bored crynlk 43742 91028 0 0 3 0x14200 bored crypto 52423 297311 0 0 3 0x40014200 acpi0 acpi0 58189 130677 0 0 3 0x14200 bored softnet 9782 391058 0 0 3 0x14200 bored systqmp 15129 138576 0 0 3 0x14200 bored systq *89844 377912 0 0 7 0x40014200 softclock 61648 123214 0 0 3 0x40014200 idle0 77011 470708 0 0 3 0x14200 bored smr 1 22689 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 9618 7031K 8379K 78643K 20721 0 0 pcb 13 13K 14K 78643K 1237 0 0 rtable 128 8K 9K 78643K 4828 0 0 ifaddr 102 25K 30K 78643K 1069 0 0 counters 19 16K 16K 78643K 19 0 0 ioctlops 0 0K 2K 78643K 407 0 0 iov 0 0K 48K 78643K 3137 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1236 78K 79K 78643K 6179 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 99 0 0 VM map 57 14K 14K 78643K 90 0 0 sem 12 0K 0K 78643K 1348 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1793 195K 288K 78643K 12645 0 0 file desc 5 13K 25K 78643K 6659 0 0 sigio 0 0K 0K 78643K 77 0 0 proc 50 38K 55K 78643K 2511 0 0 subproc 32 2K 2K 78643K 733 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 641 0 0 in_multi 31 2K 2K 78643K 807 0 0 ether_multi 1 0K 0K 78643K 44 0 0 mrt 1 0K 0K 78643K 40 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 1414 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 184 462K 478K 78643K 17455 0 0 UVM aobj 130 4K 4K 78643K 135 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 1337 0 0 NDP 25 0K 1K 78643K 359 0 0 temp 261 3545K 4185K 78643K 231384 0 0 kqueue 0 0K 0K 78643K 82 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 64 171 0 162 1 0 1 1 0 8 0 rtpcb 80 1185 0 1183 1 0 1 1 0 8 0 rtentry 112 775 0 727 2 0 2 2 0 8 0 unpcb 120 7224 0 7208 19 18 1 2 0 8 0 syncache 264 44 0 44 16 15 1 1 0 8 1 tcpqe 32 147 0 147 11 10 1 1 0 8 1 tcpcb 544 2562 0 2558 21 20 1 15 0 8 0 ipq 40 54 0 54 19 19 0 1 0 8 0 ipqe 40 657 0 657 19 19 0 1 0 8 0 inpcb 280 9573 0 9566 49 45 4 13 0 8 3 rttmr 72 16 0 16 7 7 0 1 0 8 0 ip6q 72 4 0 4 3 3 0 1 0 8 0 ip6af 40 12 0 12 3 3 0 1 0 8 0 nd6 48 101 0 98 4 3 1 1 0 8 0 pkpcb 40 16 0 16 7 6 1 1 0 8 1 ppxss 1128 109 0 109 27 26 1 1 0 8 1 art_heap8 4096 8 0 7 8 7 1 3 0 8 0 art_heap4 256 3312 0 3100 57 42 15 18 0 8 0 art_table 32 3320 0 3107 3 1 2 3 0 8 0 art_node 16 771 0 727 1 0 1 1 0 8 0 sysvmsgpl 40 60 0 51 1 0 1 1 0 8 0 semapl 112 1346 0 1336 1 0 1 1 0 8 0 shmpl 112 133 0 5 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 12080 0 10667 46 0 46 46 0 8 0 ffsino 240 12080 0 10667 84 0 84 84 0 8 0 nchpl 144 22580 0 22080 61 42 19 61 0 8 0 uvmvnodes 72 7871 0 0 144 0 144 144 0 8 0 vnodes 208 7871 0 0 415 0 415 415 0 8 0 namei 1024 81533 0 81533 5 4 1 1 0 8 1 vcpupl 1984 56 0 1 7 0 7 7 0 8 0 vmpool 520 88 0 33 5 1 4 4 0 8 0 scsiplug 64 9 0 9 5 5 0 1 0 8 0 scxspl 192 81635 0 81635 50 48 2 7 0 8 2 plimitpl 152 494 0 487 1 0 1 1 0 8 0 sigapl 432 6707 0 6694 2 0 2 2 0 8 0 futexpl 56 197650 0 197650 6 5 1 1 0 8 1 knotepl 112 1826 0 1807 3 0 3 3 0 8 2 kqueuepl 104 1768 0 1766 4 3 1 4 0 8 0 pipepl 112 7290 0 7271 29 27 2 3 0 8 1 fdescpl 424 6708 0 6694 2 0 2 2 0 8 0 filepl 120 66829 0 66734 62 56 6 11 0 8 3 lockfpl 104 2202 0 2201 1 0 1 1 0 8 0 lockfspl 48 736 0 735 1 0 1 1 0 8 0 sessionpl 112 58 0 48 1 0 1 1 0 8 0 pgrppl 48 1712 0 1702 1 0 1 1 0 8 0 ucredpl 96 7193 0 7186 1 0 1 1 0 8 0 zombiepl 144 6696 0 6695 1 0 1 1 0 8 0 processpl 864 6726 0 6695 4 0 4 4 0 8 0 procpl 632 14594 0 14557 5 1 4 5 0 8 0 sosppl 128 96 0 96 19 18 1 1 0 8 1 sockpl 384 18155 0 18130 77 70 7 21 0 8 3 mcl64k 65536 1864 0 1864 142 141 1 65 0 8 1 mcl16k 16384 88 0 88 29 28 1 1 0 8 1 mcl12k 12288 177 0 177 17 17 0 1 0 8 0 mcl9k 9216 116 0 116 24 23 1 1 0 8 1 mcl8k 8192 450 0 450 7 6 1 1 0 8 1 mcl4k 4096 1158 0 1158 8 7 1 1 0 8 1 mcl2k2 2112 63 0 63 22 22 0 1 0 8 0 mcl2k 2048 79751 0 79703 22 15 7 14 0 8 0 mtagpl 80 64 0 64 5 4 1 1 0 8 1 mbufpl 256 190064 0 189968 153 143 10 37 0 8 0 bufpl 256 31950 0 24044 495 0 495 495 0 8 0 anonpl 16 858368 0 841353 236 140 96 96 0 62 10 amapchunkpl 152 36780 0 36650 124 117 7 19 0 158 1 amappl16 192 42363 0 41245 294 228 66 69 0 8 8 amappl15 184 31 0 30 1 0 1 1 0 8 0 amappl14 176 2124 0 2121 1 0 1 1 0 8 0 amappl13 168 680 0 678 1 0 1 1 0 8 0 amappl12 160 488 0 482 1 0 1 1 0 8 0 amappl11 152 1164 0 1153 1 0 1 1 0 8 0 amappl10 144 663 0 661 1 0 1 1 0 8 0 amappl9 136 1593 0 1583 1 0 1 1 0 8 0 amappl8 128 1094 0 1052 3 1 2 2 0 8 0 amappl7 120 835 0 829 1 0 1 1 0 8 0 amappl6 112 1093 0 1082 1 0 1 1 0 8 0 amappl5 104 981 0 970 1 0 1 1 0 8 0 amappl4 96 7039 0 7010 1 0 1 1 0 8 0 amappl3 88 1266 0 1250 1 0 1 1 0 8 0 amappl2 80 50563 0 50491 3 1 2 3 0 8 0 amappl1 72 133603 0 133205 24 14 10 20 0 8 0 amappl 80 15565 0 15499 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 64 134 0 5 3 0 3 3 0 8 0 uaddrrnd 24 6796 0 6694 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 6796 0 6694 1 0 1 1 0 8 0 vmmpekpl 168 48811 0 48770 3 0 3 3 0 8 0 vmmpepl 168 826081 0 823756 469 325 144 165 0 357 34 vmsppl 272 6707 0 6694 3 2 1 2 0 8 0 pdppl 4096 13598 0 13509 13 1 12 12 0 8 0 pvpl 32 2304413 0 2285567 614 393 221 317 0 265 37 pmappl 200 6795 0 6727 4 0 4 4 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 1052 0 418 22 2 20 21 0 8 0