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 *341048 7324 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(ffffffff821e3913,ffffffff821ff6e1,2cc,ffffffff8216ac2c) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd802e3cd698) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff82556fa8) 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(ffffffff821e3913,ffffffff821ff6e1,2cc,ffffffff8216ac2c) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd802e3cd698) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff82556fa8) 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 0xffff800014812140 rbx 0xffff8000148121f0 rdx 0x2 rcx 0 rax 0 r8 0xffff800014812100 r9 0x1 r10 0 r11 0xa5c389674329778e r12 0x3000000008 r13 0xffff800014812150 r14 0x100 r15 0x1 rip 0xffffffff818bd9d8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800014812130 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (softclock) pid=341048 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff8000ffffe768,0xffff8000ffffe288 process=0xffff8000ffffc000 user=0xffff80001480d000, vmspace=0xffffffff82559af0 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 80688 184334 54873 0 2 0 syz-executor.0 80688 135296 54873 0 2 0x4000000 syz-executor.0 54873 341029 29446 0 2 0x482 syz-executor.0 59661 307951 29446 0 2 0x482 syz-executor.1 46417 432091 0 0 3 0x14200 acct acct 57776 145055 0 0 3 0x14200 bored sosplice 29446 270324 37192 0 3 0x82 thrsleep syz-fuzzer 29446 76322 37192 0 2 0x4000482 syz-fuzzer 29446 431233 37192 0 3 0x4000082 kqread syz-fuzzer 29446 11696 37192 0 3 0x4000082 thrsleep syz-fuzzer 29446 107080 37192 0 3 0x4000082 thrsleep syz-fuzzer 29446 73006 37192 0 3 0x4000082 thrsleep syz-fuzzer 29446 386383 37192 0 3 0x4000082 thrsleep syz-fuzzer 29446 23719 37192 0 3 0x4000082 thrsleep syz-fuzzer 37192 313848 18634 0 3 0x10008a pause ksh 18634 6982 15504 0 3 0x92 select sshd 80473 249512 1 0 3 0x100083 ttyin getty 15504 220307 1 0 3 0x80 select sshd 7117 49278 67336 73 3 0x100090 kqread syslogd 67336 73860 1 0 3 0x100082 netio syslogd 20893 396967 1 77 3 0x100090 poll dhclient 19171 142566 1 0 3 0x80 poll dhclient 86115 114455 0 0 2 0x14200 zerothread 61354 69940 0 0 3 0x14200 aiodoned aiodoned 98453 76624 0 0 3 0x14200 syncer update 6523 481917 0 0 3 0x14200 cleaner cleaner 30298 156288 0 0 3 0x14200 reaper reaper 80900 87200 0 0 3 0x14200 pgdaemon pagedaemon 19497 29919 0 0 3 0x14200 bored crynlk 72995 353614 0 0 3 0x14200 bored crypto 6814 466560 0 0 3 0x40014200 acpi0 acpi0 76066 322657 0 0 3 0x14200 bored softnet 88204 215792 0 0 3 0x14200 bored systqmp 53141 19318 0 0 3 0x14200 bored systq * 7324 341048 0 0 7 0x40014200 softclock 69628 483835 0 0 3 0x40014200 idle0 62820 208807 0 0 3 0x14200 bored smr 1 1729 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 9573 6996K 7755K 78643K 13472 0 0 pcb 13 8K 9K 78643K 282 0 0 rtable 104 5K 5K 78643K 1172 0 0 ifaddr 74 16K 17K 78643K 314 0 0 counters 19 16K 16K 78643K 19 0 0 ioctlops 0 0K 2K 78643K 116 0 0 iov 0 0K 24K 78643K 5820 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1219 77K 77K 78643K 2520 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 29 0 0 VM map 10 2K 2K 78643K 18 0 0 sem 12 0K 1K 78643K 11529 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1793 195K 288K 78643K 12645 0 0 file desc 5 13K 25K 78643K 4946 0 0 sigio 0 0K 0K 78643K 28 0 0 proc 49 38K 63K 78643K 931 0 0 subproc 32 2K 2K 78643K 238 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 161 0 0 in_multi 24 1K 2K 78643K 222 0 0 ether_multi 1 0K 0K 78643K 14 0 0 mrt 0 0K 0K 78643K 20 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 150 662K 662K 78643K 150 0 0 exec 0 0K 1K 78643K 526 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 103 86K 90K 78643K 11760 0 0 UVM aobj 130 4K 4K 78643K 132 0 0 memdesc 1 4K 4K 78643K 1 0 0 crypto data 1 1K 1K 78643K 1 0 0 ip6_options 0 0K 3K 78643K 902 0 0 NDP 17 0K 0K 78643K 103 0 0 temp 205 3544K 4180K 78643K 75786 0 0 kqueue 0 0K 0K 78643K 11 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 35 0 29 1 0 1 1 0 8 0 rtpcb 80 183 0 181 1 0 1 1 0 8 0 rtentry 112 223 0 184 2 0 2 2 0 8 0 unpcb 120 28288 0 28280 3 2 1 2 0 8 0 syncache 264 11 0 11 4 4 0 1 0 8 0 tcpqe 32 94 0 94 2 2 0 1 0 8 0 tcpcb 544 18152 0 18148 10 8 2 3 0 8 1 ipq 40 19 0 19 8 8 0 1 0 8 0 ipqe 40 434 0 434 8 8 0 1 0 8 0 inpcb 280 19136 0 19129 8 4 4 4 0 8 3 rttmr 72 9 0 9 4 4 0 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 31 0 29 1 0 1 1 0 8 0 pkpcb 40 16 0 16 5 5 0 1 0 8 0 swfcl 56 1 0 0 1 0 1 1 0 8 0 ppxss 1128 26 0 26 8 8 0 1 0 8 0 art_heap8 4096 8 0 7 6 5 1 3 0 8 0 art_heap4 256 999 0 814 19 5 14 15 0 8 0 art_table 32 1007 0 821 2 0 2 2 0 8 0 art_node 16 222 0 187 1 0 1 1 0 8 0 sysvmsgpl 40 80 0 60 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 11527 0 11517 1 0 1 1 0 8 0 shmpl 112 130 0 2 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 7265 0 5873 46 0 46 46 0 8 0 ffsino 240 7265 0 5873 83 0 83 83 0 8 0 nchpl 144 13098 0 11484 60 0 60 60 0 8 0 uvmvnodes 72 6079 0 0 111 0 111 111 0 8 0 vnodes 208 6079 0 0 320 0 320 320 0 8 0 namei 1024 43113 0 43113 2 1 1 1 0 8 1 vcpupl 1984 8 0 0 1 0 1 1 0 8 0 vmpool 520 16 0 8 1 0 1 1 0 8 0 scsiplug 64 2 0 2 2 2 0 1 0 8 0 scxspl 192 44024 0 44024 11 10 1 7 0 8 1 plimitpl 152 142 0 135 1 0 1 1 0 8 0 sigapl 432 5081 0 5068 2 0 2 2 0 8 0 futexpl 56 330902 0 330902 2 1 1 1 0 8 1 knotepl 112 514 0 495 1 0 1 1 0 8 0 kqueuepl 104 405 0 403 1 0 1 1 0 8 0 pipepl 112 1374 0 1355 4 3 1 2 0 8 0 fdescpl 424 5082 0 5068 2 0 2 2 0 8 0 filepl 120 67673 0 67578 17 12 5 7 0 8 2 lockfpl 104 536 0 535 1 0 1 1 0 8 0 lockfspl 48 189 0 188 1 0 1 1 0 8 0 sessionpl 112 29 0 19 1 0 1 1 0 8 0 pgrppl 48 33 0 23 1 0 1 1 0 8 0 ucredpl 96 8411 0 8404 1 0 1 1 0 8 0 zombiepl 144 5068 0 5067 1 0 1 1 0 8 0 processpl 864 5098 0 5067 4 0 4 4 0 8 0 procpl 632 10487 0 10448 4 0 4 4 0 8 0 sosppl 128 10 0 10 3 3 0 1 0 8 0 sockpl 384 47647 0 47630 21 14 7 7 0 8 5 mcl64k 65536 881 0 881 89 56 33 33 0 8 33 mcl16k 16384 19 0 19 8 7 1 1 0 8 1 mcl12k 12288 46 0 46 8 8 0 1 0 8 0 mcl9k 9216 30 0 30 6 6 0 1 0 8 0 mcl8k 8192 3629 0 3629 2 1 1 1 0 8 1 mcl4k 4096 170 0 170 5 5 0 1 0 8 0 mcl2k2 2112 12 0 12 7 7 0 1 0 8 0 mcl2k 2048 79770 0 79728 26 18 8 14 0 8 2 mtagpl 80 66 0 66 3 3 0 1 0 8 0 mbufpl 256 180485 0 180403 62 43 19 23 0 8 8 bufpl 256 16352 0 10217 387 3 384 384 0 8 0 anonpl 16 436852 0 418240 137 45 92 92 0 62 15 amapchunkpl 152 20996 0 20890 45 36 9 18 0 158 3 amappl16 192 24342 0 23288 114 49 65 65 0 8 11 amappl15 184 1 0 1 1 1 0 1 0 8 0 amappl14 176 583 0 580 1 0 1 1 0 8 0 amappl13 168 2805 0 2804 2 1 1 1 0 8 0 amappl12 160 102 0 99 1 0 1 1 0 8 0 amappl11 152 1097 0 1084 1 0 1 1 0 8 0 amappl10 144 130 0 130 3 3 0 1 0 8 0 amappl9 136 963 0 955 1 0 1 1 0 8 0 amappl8 128 480 0 450 1 0 1 1 0 8 0 amappl7 120 204 0 198 1 0 1 1 0 8 0 amappl6 112 1081 0 1072 1 0 1 1 0 8 0 amappl5 104 318 0 308 1 0 1 1 0 8 0 amappl4 96 7946 0 7919 1 0 1 1 0 8 0 amappl3 88 483 0 476 1 0 1 1 0 8 0 amappl2 80 42709 0 42639 3 1 2 3 0 8 0 amappl1 72 103957 0 103561 34 26 8 20 0 8 0 amappl 80 10915 0 10876 1 0 1 1 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 64 131 0 2 3 0 3 3 0 8 0 uaddrrnd 24 5098 0 5068 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 5098 0 5068 1 0 1 1 0 8 0 vmmpekpl 168 26518 0 26488 2 0 2 2 0 8 0 vmmpepl 168 600696 0 598573 241 117 124 132 0 357 29 vmsppl 272 5081 0 5068 3 2 1 2 0 8 0 pdppl 4096 10202 0 10160 7 1 6 6 0 8 0 pvpl 32 1182343 0 1160875 346 122 224 304 0 265 49 pmappl 200 5097 0 5076 2 0 2 2 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 714 0 157 17 0 17 17 0 8 0