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 *412341 22235 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(fffffd803cd2f0e8) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff82556fa8) 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(ffffffff821e3913,ffffffff821ff6e1,2cc,ffffffff8216ac2c) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd803cd2f0e8) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff82556fa8) 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 0xffff800014812050 rbx 0xffff800014812100 rdx 0x2 rcx 0 rax 0 r8 0xffff800014812010 r9 0x1 r10 0 r11 0x7b40926ad37fdb5a r12 0x3000000008 r13 0xffff800014812060 r14 0x100 r15 0x1 rip 0xffffffff818bd9d8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800014812040 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (softclock) pid=412341 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff8000fffff3c0,0xffff8000ffffeee0 process=0xffff8000ffffc6c0 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 96564 253954 36936 0 2 0 syz-executor.1 96564 244256 36936 0 2 0x4000000 syz-executor.1 36936 319797 45571 0 2 0x482 syz-executor.1 58273 356351 45571 0 2 0x482 syz-executor.0 59836 521326 0 0 3 0x14200 acct acct 24574 376684 1 0 3 0x100083 ttyin getty 72541 443808 0 0 3 0x14200 bored sosplice 45571 345701 10796 0 3 0x82 thrsleep syz-fuzzer 45571 240966 10796 0 3 0x4000082 thrsleep syz-fuzzer 45571 132540 10796 0 3 0x4000082 thrsleep syz-fuzzer 45571 480980 10796 0 3 0x4000082 thrsleep syz-fuzzer 45571 415219 10796 0 3 0x4000082 thrsleep syz-fuzzer 45571 59052 10796 0 3 0x4000082 thrsleep syz-fuzzer 45571 261423 10796 0 3 0x4000082 thrsleep syz-fuzzer 45571 123705 10796 0 3 0x4000082 kqread syz-fuzzer 10796 300725 15832 0 3 0x10008a pause ksh 15832 439615 85808 0 3 0x92 select sshd 85808 15133 1 0 3 0x80 select sshd 3445 179070 46881 73 3 0x100090 kqread syslogd 46881 521776 1 0 3 0x100082 netio syslogd 80905 330398 0 0 2 0x14200 zerothread 60662 447176 0 0 3 0x14200 aiodoned aiodoned 65241 169727 0 0 3 0x14200 syncer update 18602 149561 0 0 3 0x14200 cleaner cleaner 15246 189293 0 0 3 0x14200 reaper reaper 61628 427103 0 0 3 0x14200 pgdaemon pagedaemon 76804 195792 0 0 3 0x14200 bored crynlk 90792 274337 0 0 3 0x14200 bored crypto 94394 517174 0 0 3 0x40014200 acpi0 acpi0 92311 143761 0 0 3 0x14200 bored softnet 52219 311305 0 0 2 0x14200 systqmp 43661 59609 0 0 3 0x14200 bored systq *22235 412341 0 0 7 0x40014200 softclock 31779 37637 0 0 3 0x40014200 idle0 55937 225242 0 0 3 0x14200 bored smr 1 500213 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 9588 6325K 7857K 78643K 27167 0 0 pcb 13 12K 14K 78643K 1097 0 0 rtable 149 9K 9K 78643K 2196 0 0 ifaddr 100 23K 23K 78643K 1036 0 0 counters 19 16K 16K 78643K 19 0 0 ioctlops 0 0K 2K 78643K 374 0 0 iov 0 0K 32K 78643K 1314 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1224 77K 77K 78643K 6730 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 80 0 0 VM map 55 13K 13K 78643K 68 0 0 sem 12 0K 1K 78643K 1238 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1793 195K 288K 78643K 12645 0 0 file desc 5 13K 25K 78643K 5636 0 0 sigio 0 0K 0K 78643K 158 0 0 proc 44 30K 55K 78643K 2130 0 0 subproc 32 2K 2K 78643K 566 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 403 0 0 in_multi 39 2K 2K 78643K 678 0 0 ether_multi 1 0K 0K 78643K 68 0 0 mrt 2 0K 0K 78643K 43 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 180 795K 795K 78643K 180 0 0 exec 0 0K 1K 78643K 1126 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 178 381K 385K 78643K 15037 0 0 UVM aobj 130 5K 5K 78643K 136 0 0 memdesc 1 4K 4K 78643K 1 0 0 crypto data 1 1K 1K 78643K 1 0 0 ip6_options 0 0K 0K 78643K 1133 0 0 NDP 21 0K 1K 78643K 333 0 0 temp 233 3545K 4185K 78643K 339455 0 0 kqueue 0 0K 0K 78643K 42 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 64 155 0 141 1 0 1 1 0 8 0 rtpcb 80 539 0 539 11 10 1 1 0 8 1 rtentry 112 742 0 682 2 0 2 2 0 8 0 unpcb 120 2712 0 2701 3 2 1 2 0 8 0 syncache 264 42 0 42 14 14 0 1 0 8 0 tcpqe 32 154 0 154 12 12 0 1 0 8 0 tcpcb 544 2154 0 2149 20 19 1 14 0 8 0 ipq 40 37 0 37 13 13 0 1 0 8 0 ipqe 40 895 0 895 13 13 0 1 0 8 0 inpcb 280 12197 0 12184 44 41 3 13 0 8 1 rttmr 72 15 0 14 2 1 1 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 86 0 82 5 4 1 1 0 8 0 pkpcb 40 36 0 36 13 12 1 1 0 8 1 swfcl 56 2 0 0 1 0 1 1 0 8 0 ppxss 1128 118 0 118 24 23 1 1 0 8 1 art_heap8 4096 28 0 25 13 10 3 4 0 8 0 art_heap4 256 3128 0 2844 51 32 19 20 0 8 0 art_table 32 3156 0 2869 6 3 3 3 0 8 0 art_node 16 735 0 680 1 0 1 1 0 8 0 sysvmsgpl 40 78 0 52 1 0 1 1 0 8 0 semapl 112 1234 0 1224 1 0 1 1 0 8 0 shmpl 112 134 0 6 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 10347 0 8939 46 0 46 46 0 8 0 ffsino 240 10347 0 8939 84 0 84 84 0 8 0 nchpl 144 19197 0 18690 61 41 20 60 0 8 1 uvmvnodes 72 6859 0 0 125 0 125 125 0 8 0 vnodes 208 6859 0 0 361 0 361 361 0 8 0 namei 1024 68812 0 68812 5 4 1 1 0 8 1 vcpupl 1984 54 0 1 7 0 7 7 0 8 0 vmpool 520 66 0 13 4 0 4 4 0 8 0 scsiplug 64 2 0 2 2 2 0 1 0 8 0 scxspl 192 65026 0 65026 40 38 2 7 0 8 2 plimitpl 152 741 0 734 1 0 1 1 0 8 0 sigapl 432 5715 0 5704 2 0 2 2 0 8 0 futexpl 56 168318 0 168318 5 4 1 1 0 8 1 knotepl 112 1436 0 1417 3 2 1 3 0 8 0 kqueuepl 104 1518 0 1516 4 3 1 4 0 8 0 pipepl 112 5666 0 5647 19 17 2 2 0 8 1 fdescpl 424 5716 0 5704 2 0 2 2 0 8 0 filepl 120 55236 0 55149 37 32 5 10 0 8 1 lockfpl 104 4457 0 4457 5 4 1 1 0 8 1 lockfspl 48 1683 0 1683 5 4 1 1 0 8 1 sessionpl 112 49 0 41 1 0 1 1 0 8 0 pgrppl 48 110 0 102 1 0 1 1 0 8 0 ucredpl 96 8343 0 8335 1 0 1 1 0 8 0 zombiepl 144 5706 0 5705 1 0 1 1 0 8 0 processpl 864 5734 0 5705 4 0 4 4 0 8 0 procpl 632 12672 0 12635 5 0 5 5 0 8 1 sosppl 128 92 0 92 17 17 0 1 0 8 0 sockpl 384 15534 0 15518 78 73 5 21 0 8 3 mcl64k 65536 766 0 766 40 39 1 32 0 8 1 mcl16k 16384 89 0 89 21 20 1 1 0 8 1 mcl12k 12288 172 0 172 17 16 1 1 0 8 1 mcl9k 9216 94 0 94 24 24 0 1 0 8 0 mcl8k 8192 275 0 275 11 10 1 1 0 8 1 mcl4k 4096 615 0 615 9 8 1 1 0 8 1 mcl2k2 2112 51 0 51 22 22 0 1 0 8 0 mcl2k 2048 78397 0 78352 18 11 7 14 0 8 0 mtagpl 80 781 0 768 6 5 1 2 0 8 0 mbufpl 256 177965 0 177825 185 168 17 48 0 8 0 bufpl 256 26194 0 19335 429 0 429 429 0 8 0 anonpl 16 756152 0 736117 271 184 87 101 0 62 1 amapchunkpl 152 30023 0 29895 93 74 19 20 0 158 13 amappl16 192 37020 0 35815 249 178 71 76 0 8 8 amappl15 184 299 0 299 8 8 0 1 0 8 0 amappl14 176 2076 0 2070 1 0 1 1 0 8 0 amappl13 168 345 0 345 6 6 0 1 0 8 0 amappl12 160 1056 0 1052 1 0 1 1 0 8 0 amappl11 152 946 0 942 1 0 1 1 0 8 0 amappl10 144 455 0 452 1 0 1 1 0 8 0 amappl9 136 1271 0 1265 1 0 1 1 0 8 0 amappl8 128 791 0 743 2 0 2 2 0 8 0 amappl7 120 605 0 599 1 0 1 1 0 8 0 amappl6 112 888 0 874 1 0 1 1 0 8 0 amappl5 104 1469 0 1459 1 0 1 1 0 8 0 amappl4 96 4229 0 4203 1 0 1 1 0 8 0 amappl3 88 3897 0 3888 1 0 1 1 0 8 0 amappl2 80 43598 0 43534 3 1 2 3 0 8 0 amappl1 72 113334 0 112954 26 16 10 20 0 8 0 amappl 80 13458 0 13395 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 64 135 0 6 3 0 3 3 0 8 0 uaddrrnd 24 5782 0 5704 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 5782 0 5704 1 0 1 1 0 8 0 vmmpekpl 168 41421 0 41383 4 1 3 3 0 8 0 vmmpepl 168 703223 0 700785 419 278 141 152 0 357 29 vmsppl 272 5715 0 5704 2 1 1 2 0 8 0 pdppl 4096 11570 0 11487 12 1 11 11 0 8 0 pvpl 32 1874268 0 1853515 502 307 195 305 0 265 17 pmappl 200 5781 0 5717 4 0 4 4 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 905 0 325 18 0 18 18 0 8 0