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 * 60145 19633 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(ffffffff821e53c1,ffffffff821fbe00,2cc,ffffffff8216ca95) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd803db60e08) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff824fc660) 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(ffffffff821e53c1,ffffffff821fbe00,2cc,ffffffff8216ca95) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd803db60e08) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff824fc660) 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 0xffff800014812430 rbx 0xffff8000148124e0 rdx 0x2 rcx 0 rax 0 r8 0xffff8000148123f0 r9 0x1 r10 0 r11 0xbe9d62fae744cc2d r12 0x3000000008 r13 0xffff800014812440 r14 0x100 r15 0x1 rip 0xffffffff81864798 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800014812420 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (softclock) pid=60145 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff8000fffff3c0,0xffff8000ffffe9f0 process=0xffff8000ffffca20 user=0xffff80001480d000, vmspace=0xffffffff8258dd40 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 77147 311965 29143 0 3 0x82 piperd syz-executor.1 60293 500765 0 0 3 0x14200 acct acct 66775 39710 0 0 3 0x14200 bored sosplice 49936 372367 1 0 3 0x100083 ttyin getty 29143 362311 32036 0 3 0x82 thrsleep syz-fuzzer 29143 438826 32036 0 3 0x4000082 thrsleep syz-fuzzer 29143 283597 32036 0 3 0x4000082 kqread syz-fuzzer 29143 188600 32036 0 3 0x4000082 thrsleep syz-fuzzer 29143 305653 32036 0 3 0x4000082 thrsleep syz-fuzzer 29143 217432 32036 0 3 0x4000082 thrsleep syz-fuzzer 29143 21258 32036 0 3 0x4000082 thrsleep syz-fuzzer 29143 175947 32036 0 3 0x4000082 thrsleep syz-fuzzer 32036 423544 83454 0 3 0x10008a pause ksh 83454 395286 19488 0 3 0x92 select sshd 19488 287357 1 0 3 0x80 select sshd 69431 452232 47781 73 3 0x100090 kqread syslogd 47781 298949 1 0 3 0x100082 netio syslogd 29845 510702 0 0 3 0x14200 pgzero zerothread 48759 244168 0 0 3 0x14200 aiodoned aiodoned 61675 205135 0 0 3 0x14200 syncer update 73621 40411 0 0 3 0x14200 cleaner cleaner 89975 508026 0 0 3 0x14200 reaper reaper 38567 492085 0 0 3 0x14200 pgdaemon pagedaemon 61025 367056 0 0 3 0x14200 bored crynlk 21049 265354 0 0 3 0x14200 bored crypto 24357 192446 0 0 3 0x40014200 acpi0 acpi0 46484 404410 0 0 3 0x14200 bored softnet 25438 323170 0 0 3 0x14200 bored systqmp 37666 235047 0 0 3 0x14200 bored systq *19633 60145 0 0 7 0x40014200 softclock 62234 260586 0 0 3 0x40014200 idle0 34563 471380 0 0 3 0x14200 bored smr 1 492914 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 9594 6972K 15241K 78643K 21903 0 0 pcb 13 12K 14K 78643K 3443 0 0 rtable 115 8K 9K 78643K 1889 0 0 ifaddr 94 20K 22K 78643K 949 0 0 counters 19 16K 16K 78643K 19 0 0 ioctlops 0 0K 2K 78643K 367 0 0 iov 0 0K 28K 78643K 1294 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1214 76K 77K 78643K 5979 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 62 15K 15K 78643K 85 0 0 sem 12 1K 1K 78643K 1397 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1793 195K 288K 78643K 12645 0 0 file desc 3 5K 25K 78643K 5356 0 0 sigio 0 0K 0K 78643K 114 0 0 proc 44 30K 63K 78643K 2217 0 0 subproc 16 1K 2K 78643K 612 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 500 0 0 in_multi 23 1K 2K 78643K 566 0 0 ether_multi 1 0K 0K 78643K 47 0 0 mrt 3 0K 0K 78643K 54 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 1297 0 0 pfkey data 0 0K 4K 78643K 8 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 201 535K 548K 78643K 14394 0 0 UVM aobj 130 6K 6K 78643K 148 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 1154 0 0 NDP 24 0K 1K 78643K 323 0 0 temp 239 3540K 4192K 78643K 199242 0 0 kqueue 0 0K 0K 78643K 49 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 64 126 0 120 1 0 1 1 0 8 0 rtpcb 80 591 0 591 12 11 1 1 0 8 1 rtentry 112 595 0 555 2 0 2 2 0 8 0 unpcb 120 8850 0 8838 10 9 1 2 0 8 0 syncache 264 33 0 33 16 15 1 1 0 8 1 tcpqe 32 83 0 83 9 8 1 1 0 8 1 tcpcb 544 2327 0 2323 22 21 1 12 0 8 0 ipq 40 55 0 55 21 21 0 1 0 8 0 ipqe 40 1671 0 1671 21 21 0 1 0 8 0 inpcb 280 8682 0 8678 46 38 8 13 0 8 7 rttmr 72 21 0 20 7 6 1 1 0 8 0 ip6q 72 5 0 5 4 4 0 1 0 8 0 ip6af 40 12 0 12 3 3 0 1 0 8 0 nd6 48 77 0 75 10 9 1 1 0 8 0 pkpcb 40 20 0 20 9 9 0 1 0 8 0 swfcl 56 11 0 0 1 0 1 1 0 8 0 ppxss 1128 118 0 117 10 9 1 1 0 8 0 art_heap8 4096 7 0 6 6 4 2 3 0 8 1 art_heap4 256 2433 0 2220 50 36 14 18 0 8 0 art_table 32 2440 0 2226 7 5 2 3 0 8 0 art_node 16 593 0 557 1 0 1 1 0 8 0 sysvmsgpl 40 53 0 31 1 0 1 1 0 8 0 semupl 112 3 0 3 1 1 0 1 0 8 0 semapl 112 1393 0 1383 1 0 1 1 0 8 0 shmpl 112 146 0 18 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 9647 0 8248 46 0 46 46 0 8 0 ffsino 240 9647 0 8248 83 0 83 83 0 8 0 nchpl 144 18807 0 17171 63 1 62 62 0 8 0 uvmvnodes 72 6600 0 0 120 0 120 120 0 8 0 vnodes 208 6600 0 0 348 0 348 348 0 8 0 namei 1024 63803 0 63803 4 3 1 1 0 8 1 vcpupl 1984 60 0 0 8 0 8 8 0 8 0 vmpool 520 83 0 23 5 1 4 5 0 8 0 scsiplug 64 2 0 2 2 2 0 1 0 8 0 scxspl 192 57613 0 57613 31 29 2 7 0 8 2 plimitpl 152 489 0 484 1 0 1 1 0 8 0 sigapl 432 5426 0 5417 2 0 2 2 0 8 0 futexpl 56 157082 0 157082 5 4 1 1 0 8 1 knotepl 112 1757 0 1744 6 5 1 3 0 8 0 kqueuepl 104 3100 0 3098 4 3 1 4 0 8 0 pipepl 112 3576 0 3563 13 12 1 2 0 8 0 fdescpl 424 5427 0 5417 2 0 2 2 0 8 0 filepl 120 55023 0 54962 35 26 9 10 0 8 6 lockfpl 104 2240 0 2240 6 5 1 1 0 8 1 lockfspl 48 633 0 633 6 5 1 1 0 8 1 sessionpl 112 52 0 45 1 0 1 1 0 8 0 pgrppl 48 600 0 593 1 0 1 1 0 8 0 ucredpl 96 5628 0 5621 1 0 1 1 0 8 0 zombiepl 144 5419 0 5419 1 0 1 1 0 8 1 processpl 864 5445 0 5419 4 0 4 4 0 8 0 procpl 632 11880 0 11847 4 0 4 4 0 8 0 sosppl 128 95 0 95 18 18 0 1 0 8 0 sockpl 384 18264 0 18248 77 67 10 22 0 8 7 mcl64k 65536 1337 0 1337 100 99 1 33 0 8 1 mcl16k 16384 63 0 63 23 23 0 1 0 8 0 mcl12k 12288 180 0 180 17 16 1 1 0 8 1 mcl9k 9216 103 0 103 22 21 1 1 0 8 1 mcl8k 8192 259 0 259 12 11 1 1 0 8 1 mcl4k 4096 653 0 653 9 8 1 1 0 8 1 mcl2k2 2112 59 0 59 20 19 1 1 0 8 1 mcl2k 2048 74771 0 74731 18 12 6 13 0 8 0 mtagpl 80 200 0 192 8 7 1 1 0 8 0 mbufpl 256 167762 0 167671 230 222 8 35 0 8 0 bufpl 256 27731 0 21131 413 0 413 413 0 8 0 anonpl 16 685260 0 671669 222 135 87 89 0 62 10 amapchunkpl 152 28059 0 27956 88 78 10 19 0 158 5 amappl16 192 33134 0 32054 273 209 64 67 0 8 8 amappl15 184 657 0 656 1 0 1 1 0 8 0 amappl14 176 1154 0 1151 2 1 1 1 0 8 0 amappl13 168 381 0 380 3 2 1 1 0 8 0 amappl12 160 954 0 952 1 0 1 1 0 8 0 amappl11 152 1202 0 1198 1 0 1 1 0 8 0 amappl10 144 27 0 25 1 0 1 1 0 8 0 amappl9 136 1779 0 1773 1 0 1 1 0 8 0 amappl8 128 1315 0 1265 3 1 2 2 0 8 0 amappl7 120 215 0 207 1 0 1 1 0 8 0 amappl6 112 1139 0 1127 1 0 1 1 0 8 0 amappl5 104 1418 0 1409 1 0 1 1 0 8 0 amappl4 96 5092 0 5069 1 0 1 1 0 8 0 amappl3 88 1966 0 1954 1 0 1 1 0 8 0 amappl2 80 41155 0 41096 3 1 2 3 0 8 0 amappl1 72 109478 0 109128 27 18 9 20 0 8 0 amappl 80 12709 0 12648 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 64 147 0 18 3 0 3 3 0 8 0 uaddrrnd 24 5510 0 5417 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 5510 0 5417 1 0 1 1 0 8 0 vmmpekpl 168 35155 0 35111 3 0 3 3 0 8 0 vmmpepl 168 667300 0 665245 447 311 136 154 0 357 33 vmsppl 272 5426 0 5417 2 1 1 2 0 8 0 pdppl 4096 11026 0 10940 15 3 12 12 0 8 0 pvpl 32 1684166 0 1668273 494 294 200 254 0 265 25 pmappl 200 5509 0 5440 4 0 4 4 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 992 0 445 17 0 17 17 0 8 0