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 *206971 86868 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(ffffffff821e553b,ffffffff821fe2db,2cc,ffffffff8216cb2b) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd802d624d98) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff8250d6f0) at arptimer+0x95 sys/netinet/if_ether.c:120 softclock_thread(ffff8000ffffec58) at softclock_thread+0x145 timeout_run sys/kern/kern_timeout.c:480 [inline] softclock_thread(ffff8000ffffec58) at softclock_thread+0x145 sys/kern/kern_timeout.c:563 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(ffffffff821e553b,ffffffff821fe2db,2cc,ffffffff8216cb2b) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd802d624d98) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff8250d6f0) at arptimer+0x95 sys/netinet/if_ether.c:120 softclock_thread(ffff8000ffffec58) at softclock_thread+0x145 timeout_run sys/kern/kern_timeout.c:480 [inline] softclock_thread(ffff8000ffffec58) at softclock_thread+0x145 sys/kern/kern_timeout.c:563 end trace frame: 0x0, count: -6 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff800014811dd0 rbx 0xffff800014811e80 rdx 0x2 rcx 0 rax 0 r8 0xffff800014811d90 r9 0x1 r10 0 r11 0xcda8fbb2cb4bff2b r12 0x3000000008 r13 0xffff800014811de0 r14 0x100 r15 0x1 rip 0xffffffff81cff578 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800014811dc0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (softclock) pid=206971 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff8000ffffeed0,0xffff8000ffffe9f0 process=0xffff8000ffffc6c0 user=0xffff80001480d000, vmspace=0xffffffff82593660 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 34779 369465 50581 60929 2 0x10 syz-executor.0 34779 480810 50581 60929 2 0x4000010 syz-executor.0 34779 224197 50581 60929 3 0x4000010 inode syz-executor.0 17585 478427 73505 0 2 0x480 syz-executor.1 17585 29552 73505 0 3 0x4000080 netio syz-executor.1 17585 81153 73505 0 3 0x4000080 fsleep syz-executor.1 73505 262379 20284 0 2 0x482 syz-executor.1 50581 412895 20284 0 2 0x482 syz-executor.0 22278 433128 0 0 3 0x14200 acct acct 33405 507816 0 0 3 0x14200 bored sosplice 20284 132289 10196 0 3 0x82 thrsleep syz-fuzzer 20284 197358 10196 0 3 0x4000082 thrsleep syz-fuzzer 20284 346223 10196 0 3 0x4000082 thrsleep syz-fuzzer 20284 40421 10196 0 3 0x4000082 thrsleep syz-fuzzer 20284 86689 10196 0 3 0x4000082 kqread syz-fuzzer 20284 31348 10196 0 3 0x4000082 thrsleep syz-fuzzer 20284 97449 10196 0 3 0x4000082 thrsleep syz-fuzzer 20284 184258 10196 0 3 0x4000082 thrsleep syz-fuzzer 10196 33541 81895 0 3 0x10008a pause ksh 81895 372715 10553 0 3 0x92 select sshd 65235 346829 1 0 3 0x100083 ttyin getty 10553 219202 1 0 3 0x80 select sshd 76210 40067 19719 73 3 0x100090 kqread syslogd 19719 93784 1 0 3 0x100082 netio syslogd 14604 203704 1 77 3 0x100090 poll dhclient 35375 455678 1 0 3 0x80 poll dhclient 70612 226756 0 0 2 0x14200 zerothread 19452 190916 0 0 3 0x14200 aiodoned aiodoned 23711 347430 0 0 3 0x14200 syncer update 35351 215026 0 0 3 0x14200 cleaner cleaner 65999 29502 0 0 3 0x14200 reaper reaper 62078 399914 0 0 3 0x14200 pgdaemon pagedaemon 22561 411039 0 0 3 0x14200 bored crynlk 81190 212234 0 0 3 0x14200 bored crypto 71583 88764 0 0 3 0x40014200 acpi0 acpi0 85028 423521 0 0 3 0x14200 bored softnet 81846 409567 0 0 3 0x14200 bored systqmp 26554 170035 0 0 3 0x14200 bored systq *86868 206971 0 0 7 0x40014200 softclock 95566 374524 0 0 3 0x40014200 idle0 4452 289395 0 0 3 0x14200 bored smr 1 89793 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 9610 6390K 8798K 78643K 39579 0 0 pcb 13 11K 12K 78643K 1867 0 0 rtable 113 13K 14K 78643K 3356 0 0 ifaddr 101 22K 24K 78643K 1100 0 0 counters 19 16K 16K 78643K 19 0 0 ioctlops 0 0K 2K 78643K 375 0 0 iov 0 0K 28K 78643K 1367 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1244 78K 80K 78643K 10139 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 77 0 0 VM map 38 9K 9K 78643K 54 0 0 sem 12 0K 1K 78643K 1401 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1793 195K 288K 78643K 12645 0 0 file desc 6 17K 25K 78643K 5652 0 0 sigio 0 0K 1K 78643K 525 0 0 proc 49 38K 63K 78643K 2163 0 0 subproc 32 2K 2K 78643K 595 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 1171 0 0 in_multi 21 1K 2K 78643K 597 0 0 ether_multi 1 0K 0K 78643K 53 0 0 mrt 0 0K 0K 78643K 170 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 96 424K 424K 78643K 96 0 0 exec 0 0K 1K 78643K 1252 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 189 269K 285K 78643K 15207 0 0 UVM aobj 130 4K 4K 78643K 169 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 3425 0 0 NDP 24 0K 1K 78643K 286 0 0 temp 254 3545K 3626K 78643K 151557 0 0 kqueue 0 0K 0K 78643K 78 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 64 100 0 95 1 0 1 1 0 8 0 rtpcb 80 554 0 552 1 0 1 1 0 8 0 rtentry 112 580 0 543 2 0 2 2 0 8 0 unpcb 120 3344 0 3332 4 3 1 2 0 8 0 syncache 264 31 0 31 12 12 0 1 0 8 0 tcpqe 32 156 0 156 8 8 0 1 0 8 0 tcpcb 544 3484 0 3480 33 32 1 13 0 8 0 ipq 40 127 0 127 19 18 1 1 0 8 1 ipqe 40 4010 0 4010 19 18 1 1 0 8 1 inpcb 280 11094 0 11086 35 33 2 9 0 8 1 rttmr 72 63 0 63 7 7 0 1 0 8 0 ip6q 72 1 0 1 1 1 0 1 0 8 0 ip6af 40 2 0 2 1 1 0 1 0 8 0 nd6 48 78 0 78 4 3 1 1 0 8 1 pkpcb 40 8 0 8 4 4 0 1 0 8 0 swfcl 56 1 0 0 1 0 1 1 0 8 0 ppxss 1128 109 0 109 22 21 1 1 0 8 1 art_heap8 4096 4 0 2 4 2 2 4 0 8 0 art_heap4 256 2104 0 1956 32 17 15 16 0 8 2 art_table 32 2108 0 1958 2 0 2 2 0 8 0 art_node 16 572 0 541 1 0 1 1 0 8 0 sysvmsgpl 40 107 0 71 2 1 1 1 0 8 0 semupl 112 3 0 3 1 1 0 1 0 8 0 semapl 112 1399 0 1389 1 0 1 1 0 8 0 shmpl 112 167 0 39 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 9877 0 8458 46 0 46 46 0 8 0 ffsino 240 9877 0 8458 84 0 84 84 0 8 0 nchpl 144 19304 0 18852 60 40 20 60 0 8 0 uvmvnodes 72 7979 0 0 146 0 146 146 0 8 0 vnodes 208 7979 0 0 420 0 420 420 0 8 0 namei 1024 69349 0 69348 2 1 1 1 0 8 0 vcpupl 1984 36 0 0 5 0 5 5 0 8 0 vmpool 520 52 0 16 3 0 3 3 0 8 0 scsiplug 64 2 0 2 2 2 0 1 0 8 0 scxspl 192 62405 0 62405 29 27 2 7 0 8 2 plimitpl 152 522 0 515 1 0 1 1 0 8 0 sigapl 432 5723 0 5709 2 0 2 2 0 8 0 futexpl 56 170710 0 170709 2 1 1 1 0 8 0 knotepl 112 1426 0 1407 7 6 1 2 0 8 0 kqueuepl 104 1881 0 1879 4 3 1 4 0 8 0 pipepl 112 3784 0 3761 17 16 1 2 0 8 0 fdescpl 424 5724 0 5709 2 0 2 2 0 8 0 filepl 120 55228 0 55124 39 35 4 10 0 8 0 lockfpl 104 2206 0 2205 1 0 1 1 0 8 0 lockfspl 48 703 0 702 1 0 1 1 0 8 0 sessionpl 112 50 0 40 1 0 1 1 0 8 0 pgrppl 48 189 0 179 1 0 1 1 0 8 0 ucredpl 96 7320 0 7311 1 0 1 1 0 8 0 zombiepl 144 5712 0 5712 1 0 1 1 0 8 1 processpl 864 5743 0 5712 4 0 4 4 0 8 0 procpl 632 12749 0 12707 9 5 4 5 0 8 0 sosppl 128 100 0 100 22 22 0 1 0 8 0 sockpl 384 15162 0 15140 74 70 4 14 0 8 1 mcl64k 65536 852 0 852 43 42 1 33 0 8 1 mcl16k 16384 82 0 82 25 25 0 1 0 8 0 mcl12k 12288 155 0 155 17 16 1 1 0 8 1 mcl9k 9216 94 0 94 25 24 1 1 0 8 1 mcl8k 8192 349 0 349 8 7 1 1 0 8 1 mcl4k 4096 709 0 709 7 6 1 1 0 8 1 mcl2k2 2112 58 0 58 23 22 1 1 0 8 1 mcl2k 2048 80791 0 80746 20 13 7 15 0 8 0 mtagpl 80 243 0 243 7 6 1 1 0 8 1 mbufpl 256 225332 0 225237 309 291 18 66 0 8 4 bufpl 256 31377 0 23397 499 0 499 499 0 8 0 anonpl 16 734061 0 713395 279 179 100 101 0 62 13 amapchunkpl 152 31842 0 31680 95 79 16 16 0 158 8 amappl16 192 34415 0 33207 263 200 63 74 0 8 2 amappl15 184 1785 0 1785 3 3 0 1 0 8 0 amappl14 176 1230 0 1224 1 0 1 1 0 8 0 amappl13 168 101 0 101 5 5 0 1 0 8 0 amappl12 160 297 0 295 2 1 1 1 0 8 0 amappl11 152 676 0 664 1 0 1 1 0 8 0 amappl10 144 595 0 592 1 0 1 1 0 8 0 amappl9 136 1771 0 1766 1 0 1 1 0 8 0 amappl8 128 1372 0 1312 4 1 3 3 0 8 0 amappl7 120 772 0 764 1 0 1 1 0 8 0 amappl6 112 614 0 598 1 0 1 1 0 8 0 amappl5 104 742 0 733 1 0 1 1 0 8 0 amappl4 96 5012 0 4979 1 0 1 1 0 8 0 amappl3 88 2282 0 2268 1 0 1 1 0 8 0 amappl2 80 44222 0 44142 3 1 2 3 0 8 0 amappl1 72 115632 0 115194 26 17 9 20 0 8 0 amappl 80 13571 0 13507 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 64 168 0 39 3 0 3 3 0 8 0 uaddrrnd 24 5776 0 5709 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 5776 0 5709 1 0 1 1 0 8 0 vmmpekpl 168 38311 0 38268 3 0 3 3 0 8 0 vmmpepl 168 703326 0 700773 418 271 147 160 0 357 36 vmsppl 272 5723 0 5709 6 5 1 2 0 8 0 pdppl 4096 11558 0 11486 12 2 10 10 0 8 0 pvpl 32 1949820 0 1926634 652 335 317 317 0 265 124 pmappl 200 5775 0 5725 3 0 3 3 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 1089 0 445 21 1 20 20 0 8 0