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 * 26090 56105 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(ffffffff821e5265,ffffffff82200e56,2cc,ffffffff8216c9b5) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd802dee53f8) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff825366f0) 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(ffffffff821e5265,ffffffff82200e56,2cc,ffffffff8216c9b5) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd802dee53f8) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff825366f0) 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 0xffff8000148123b0 rbx 0xffff800014812460 rdx 0x2 rcx 0 rax 0 r8 0xffff800014812370 r9 0x1 r10 0 r11 0x1c4cfaa8498f22fa r12 0x3000000008 r13 0xffff8000148123c0 r14 0x100 r15 0x1 rip 0xffffffff81c0cb78 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000148123a0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (softclock) pid=26090 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff8000ffffe4f0,0xffff8000ffffe288 process=0xffff8000ffffc000 user=0xffff80001480d000, vmspace=0xffffffff825637d0 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 92256 401409 47280 0 2 0x480 syz-executor.1 92256 201669 47280 0 3 0x4000080 netio syz-executor.1 92256 153020 47280 0 3 0x4000080 fsleep syz-executor.1 29653 435875 33539 0 2 0x480 syz-executor.0 29653 377620 33539 0 3 0x4000080 ttyout syz-executor.0 29653 205967 33539 0 3 0x4000080 poll syz-executor.0 29653 153318 33539 0 3 0x4000080 fsleep syz-executor.0 55216 99225 1 0 3 0x100083 ttyin getty 33539 307383 67107 0 2 0x482 syz-executor.0 47280 449725 67107 0 2 0x482 syz-executor.1 13714 405995 0 0 3 0x14200 acct acct 87145 15514 0 0 3 0x14200 bored sosplice 67107 188904 41225 0 3 0x82 thrsleep syz-fuzzer 67107 203018 41225 0 3 0x4000082 thrsleep syz-fuzzer 67107 235769 41225 0 3 0x4000082 thrsleep syz-fuzzer 67107 201311 41225 0 3 0x4000082 thrsleep syz-fuzzer 67107 480676 41225 0 3 0x4000082 thrsleep syz-fuzzer 67107 479308 41225 0 3 0x4000082 kqread syz-fuzzer 67107 286395 41225 0 3 0x4000082 thrsleep syz-fuzzer 67107 163284 41225 0 3 0x4000082 thrsleep syz-fuzzer 41225 335473 95888 0 3 0x10008a pause ksh 95888 174976 71918 0 3 0x92 select sshd 71918 49815 1 0 3 0x80 select sshd 62678 268541 35034 73 3 0x100090 kqread syslogd 35034 270221 1 0 3 0x100082 netio syslogd 72994 204149 0 0 3 0x14200 pgzero zerothread 40653 406401 0 0 3 0x14200 aiodoned aiodoned 41155 60567 0 0 3 0x14200 syncer update 45930 239280 0 0 3 0x14200 cleaner cleaner 40046 91570 0 0 3 0x14200 reaper reaper 37574 102472 0 0 3 0x14200 pgdaemon pagedaemon 18494 28707 0 0 3 0x14200 bored crynlk 18237 448950 0 0 3 0x14200 bored crypto 28633 368713 0 0 3 0x40014200 acpi0 acpi0 87210 156336 0 0 3 0x14200 bored softnet 87757 357124 0 0 2 0x14200 systqmp 27109 495366 0 0 3 0x14200 bored systq *56105 26090 0 0 7 0x40014200 softclock 11157 413427 0 0 3 0x40014200 idle0 58887 113982 0 0 3 0x14200 bored smr 1 218469 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 9565 6949K 7561K 78643K 18179 0 0 pcb 13 12K 14K 78643K 845 0 0 rtable 103 12K 13K 78643K 1746 0 0 ifaddr 78 18K 20K 78643K 755 0 0 counters 19 16K 16K 78643K 19 0 0 ioctlops 0 0K 2K 78643K 243 0 0 iov 0 0K 32K 78643K 910 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1226 77K 78K 78643K 4316 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 62 0 0 VM map 45 11K 11K 78643K 59 0 0 sem 12 0K 1K 78643K 1075 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1793 195K 288K 78643K 12645 0 0 file desc 6 17K 25K 78643K 4122 0 0 sigio 0 0K 0K 78643K 88 0 0 proc 43 30K 55K 78643K 1726 0 0 subproc 32 2K 2K 78643K 433 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 393 0 0 in_multi 21 1K 2K 78643K 539 0 0 ether_multi 1 0K 0K 78643K 35 0 0 mrt 0 0K 0K 78643K 34 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 925 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 172 315K 324K 78643K 11642 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 1 0K 4K 78643K 5904 0 0 NDP 18 0K 1K 78643K 250 0 0 temp 212 3544K 4184K 78643K 183358 0 0 kqueue 0 0K 0K 78643K 47 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 97 0 91 1 0 1 1 0 8 0 rtpcb 80 347 0 347 12 11 1 1 0 8 1 rtentry 112 526 0 489 2 0 2 2 0 8 0 unpcb 120 2874 0 2867 3 2 1 2 0 8 0 syncache 264 25 0 25 11 11 0 1 0 8 0 tcpqe 32 79 0 79 8 8 0 1 0 8 0 tcpcb 544 2327 0 2323 34 33 1 15 0 8 0 ipq 40 40 0 39 20 19 1 1 0 8 0 ipqe 40 827 0 826 20 19 1 1 0 8 0 inpcb 280 10081 0 10076 42 40 2 13 0 8 1 rttmr 72 16 0 15 5 4 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 72 0 71 2 1 1 1 0 8 0 pkpcb 40 28 0 28 9 9 0 1 0 8 0 swfcl 56 6 0 0 1 0 1 1 0 8 0 ppxss 1128 87 0 87 20 19 1 1 0 8 1 art_heap8 4096 5 0 4 5 4 1 3 0 8 0 art_heap4 256 2354 0 2147 32 17 15 17 0 8 0 art_table 32 2359 0 2151 4 2 2 3 0 8 0 art_node 16 525 0 487 1 0 1 1 0 8 0 sysvmsgpl 40 64 0 52 1 0 1 1 0 8 0 semupl 112 3 0 3 1 1 0 1 0 8 0 semapl 112 1071 0 1061 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 7898 0 6482 46 0 46 46 0 8 0 ffsino 240 7898 0 6482 84 0 84 84 0 8 0 nchpl 144 14911 0 14439 60 40 20 60 0 8 0 uvmvnodes 72 7271 0 0 133 0 133 133 0 8 0 vnodes 208 7271 0 0 383 0 383 383 0 8 0 namei 1024 50107 0 50107 3 2 1 1 0 8 1 vcpupl 1984 43 0 0 6 0 6 6 0 8 0 vmpool 520 57 0 14 3 0 3 3 0 8 0 scsiplug 64 8 0 8 5 5 0 1 0 8 0 scxspl 192 59493 0 59493 33 32 1 7 0 8 1 plimitpl 152 371 0 365 1 0 1 1 0 8 0 sigapl 432 4230 0 4218 2 0 2 2 0 8 0 futexpl 56 124248 0 124246 4 3 1 1 0 8 0 knotepl 112 1198 0 1179 3 2 1 2 0 8 0 kqueuepl 104 1483 0 1481 7 6 1 4 0 8 0 pipepl 112 3452 0 3433 17 16 1 2 0 8 0 fdescpl 424 4231 0 4218 2 0 2 2 0 8 0 filepl 120 41350 0 41259 37 33 4 10 0 8 0 lockfpl 104 1611 0 1611 3 2 1 1 0 8 1 lockfspl 48 561 0 561 3 2 1 1 0 8 1 sessionpl 112 46 0 38 1 0 1 1 0 8 0 pgrppl 48 96 0 88 1 0 1 1 0 8 0 ucredpl 96 5710 0 5703 1 0 1 1 0 8 0 zombiepl 144 4220 0 4220 1 0 1 1 0 8 1 processpl 864 4249 0 4220 4 0 4 4 0 8 0 procpl 632 9646 0 9605 4 0 4 4 0 8 0 sosppl 128 52 0 52 15 15 0 1 0 8 0 sockpl 384 13395 0 13382 76 72 4 21 0 8 2 mcl64k 65536 382 0 382 10 9 1 1 0 8 1 mcl16k 16384 46 0 46 19 19 0 1 0 8 0 mcl12k 12288 128 0 128 17 16 1 1 0 8 1 mcl9k 9216 70 0 70 19 18 1 1 0 8 1 mcl8k 8192 232 0 232 10 9 1 1 0 8 1 mcl4k 4096 434 0 434 6 5 1 1 0 8 1 mcl2k2 2112 44 0 44 15 14 1 1 0 8 1 mcl2k 2048 75089 0 75044 25 18 7 14 0 8 0 mtagpl 80 130 0 130 4 4 0 1 0 8 0 mbufpl 256 165090 0 164989 119 110 9 31 0 8 0 bufpl 256 27212 0 19898 458 0 458 458 0 8 0 anonpl 16 565146 0 543662 224 121 103 103 0 62 14 amapchunkpl 152 24180 0 24007 84 76 8 20 0 158 1 amappl16 192 26136 0 24921 229 157 72 74 0 8 8 amappl15 184 1363 0 1362 1 0 1 1 0 8 0 amappl14 176 1368 0 1359 1 0 1 1 0 8 0 amappl13 168 181 0 181 3 3 0 1 0 8 0 amappl12 160 269 0 265 1 0 1 1 0 8 0 amappl11 152 306 0 302 1 0 1 1 0 8 0 amappl10 144 443 0 443 3 3 0 1 0 8 0 amappl9 136 1638 0 1632 1 0 1 1 0 8 0 amappl8 128 1211 0 1169 2 0 2 2 0 8 0 amappl7 120 553 0 546 1 0 1 1 0 8 0 amappl6 112 280 0 268 1 0 1 1 0 8 0 amappl5 104 609 0 600 1 0 1 1 0 8 0 amappl4 96 4316 0 4289 1 0 1 1 0 8 0 amappl3 88 1186 0 1171 1 0 1 1 0 8 0 amappl2 80 32551 0 32474 3 1 2 3 0 8 0 amappl1 72 89245 0 88834 26 16 10 20 0 8 0 amappl 80 10303 0 10238 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 4288 0 4218 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 4288 0 4218 1 0 1 1 0 8 0 vmmpekpl 168 32052 0 32016 2 0 2 2 0 8 0 vmmpepl 168 524322 0 521772 392 271 121 147 0 357 7 vmsppl 272 4230 0 4218 2 1 1 2 0 8 0 pdppl 4096 8582 0 8507 12 2 10 10 0 8 0 pvpl 32 1489056 0 1467079 527 300 227 316 0 265 46 pmappl 200 4287 0 4232 4 1 3 3 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 824 0 231 18 0 18 18 0 8 0