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 *361086 25358 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(ffffffff821e8d7c,ffffffff822046f4,2cc,ffffffff8217306b) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd802e0b9a88) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff8255a090) at arptimer+0x95 sys/netinet/if_ether.c:120 softclock_thread(ffff8000ffffeed0) at softclock_thread+0x145 timeout_run sys/kern/kern_timeout.c:475 [inline] softclock_thread(ffff8000ffffeed0) 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(ffffffff821e8d7c,ffffffff822046f4,2cc,ffffffff8217306b) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd802e0b9a88) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff8255a090) at arptimer+0x95 sys/netinet/if_ether.c:120 softclock_thread(ffff8000ffffeed0) at softclock_thread+0x145 timeout_run sys/kern/kern_timeout.c:475 [inline] softclock_thread(ffff8000ffffeed0) at softclock_thread+0x145 sys/kern/kern_timeout.c:552 end trace frame: 0x0, count: -6 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff800014812160 rbx 0xffff800014812210 rdx 0x2 rcx 0 rax 0 r8 0xffff800014812120 r9 0x1 r10 0 r11 0xcead072841b10c8a r12 0x3000000008 r13 0xffff800014812170 r14 0x100 r15 0x1 rip 0xffffffff81863bd8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800014812150 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (softclock) pid=361086 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff8000fffff148,0xffff8000ffffe778 process=0xffff8000ffffc000 user=0xffff80001480d000, vmspace=0xffffffff8255fa48 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 51744 270802 1417 0 2 0x480 syz-executor.0 51744 265917 1417 0 3 0x4000080 ttyout syz-executor.0 51744 297075 1417 0 3 0x4000080 ttyin syz-executor.0 51744 211818 1417 0 3 0x4000080 ttyout syz-executor.0 1417 317077 62855 0 2 0x482 syz-executor.0 4518 666 62855 0 3 0x82 piperd syz-executor.1 89296 327296 1 0 3 0x100083 ttyin getty 33976 333341 0 0 3 0x14200 bored sosplice 62855 463663 49456 0 3 0x82 thrsleep syz-fuzzer 62855 44987 49456 0 3 0x4000082 thrsleep syz-fuzzer 62855 274766 49456 0 3 0x4000082 thrsleep syz-fuzzer 62855 455937 49456 0 3 0x4000082 thrsleep syz-fuzzer 62855 141387 49456 0 3 0x4000082 thrsleep syz-fuzzer 62855 458692 49456 0 3 0x4000082 thrsleep syz-fuzzer 62855 514725 49456 0 3 0x4000082 thrsleep syz-fuzzer 62855 22059 49456 0 3 0x4000082 kqread syz-fuzzer 49456 183241 31246 0 3 0x10008a pause ksh 31246 58843 25881 0 3 0x92 select sshd 25881 107036 1 0 3 0x80 select sshd 79933 338595 93911 73 3 0x100090 kqread syslogd 93911 472971 1 0 3 0x100082 netio syslogd 42328 57835 1 77 3 0x100090 poll dhclient 98442 144057 1 0 3 0x80 poll dhclient 73360 200875 0 0 3 0x14200 pgzero zerothread 69828 216087 0 0 3 0x14200 aiodoned aiodoned 96946 58617 0 0 3 0x14200 syncer update 40840 231524 0 0 3 0x14200 cleaner cleaner 37141 178021 0 0 3 0x14200 reaper reaper 82082 458819 0 0 3 0x14200 pgdaemon pagedaemon 80343 76890 0 0 3 0x14200 bored crynlk 76771 407694 0 0 3 0x14200 bored crypto 26388 460499 0 0 3 0x40014200 acpi0 acpi0 69220 455167 0 0 3 0x14200 bored softnet 684 51776 0 0 3 0x14200 bored systqmp 13642 504287 0 0 3 0x14200 bored systq *25358 361086 0 0 7 0x40014200 softclock 22826 203647 0 0 3 0x40014200 idle0 75768 110219 0 0 3 0x14200 bored smr 1 507569 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 9591 6388K 7897K 78643K 21596 0 0 pcb 13 12K 14K 78643K 801 0 0 rtable 123 12K 13K 78643K 5382 0 0 ifaddr 87 19K 21K 78643K 666 0 0 counters 19 16K 16K 78643K 19 0 0 ioctlops 0 0K 2K 78643K 249 0 0 iov 0 0K 32K 78643K 857 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1213 76K 77K 78643K 5562 0 0 UFS quota 1 32K 32K 78643K 1 0 0 UFS mount 5 36K 36K 78643K 5 0 0 shm 2 1K 9K 78643K 59 0 0 VM map 34 8K 8K 78643K 48 0 0 sem 12 0K 1K 78643K 1398 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1793 195K 288K 78643K 12645 0 0 file desc 5 13K 25K 78643K 3946 0 0 sigio 0 0K 0K 78643K 61 0 0 proc 50 38K 63K 78643K 1533 0 0 subproc 32 2K 2K 78643K 408 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 379 0 0 in_multi 21 1K 2K 78643K 537 0 0 ether_multi 1 0K 0K 78643K 24 0 0 mrt 0 0K 0K 78643K 16 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 102 450K 450K 78643K 102 0 0 exec 0 0K 1K 78643K 835 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 159 267K 276K 78643K 11820 0 0 UVM aobj 130 4K 4K 78643K 134 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 792 0 0 NDP 22 0K 1K 78643K 228 0 0 temp 241 3545K 4180K 78643K 163860 0 0 kqueue 0 0K 0K 78643K 82 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 64 273 0 264 1 0 1 1 0 8 0 rtpcb 80 1774 0 1772 1 0 1 1 0 8 0 rtentry 112 1072 0 1028 2 0 2 2 0 8 0 unpcb 120 1932 0 1923 1 0 1 1 0 8 0 syncache 264 30 0 30 11 11 0 1 0 8 0 tcpqe 32 78 0 78 5 5 0 1 0 8 0 tcpcb 544 2245 0 2241 60 59 1 15 0 8 0 ipq 40 34 0 34 10 10 0 1 0 8 0 ipqe 40 357 0 357 10 10 0 1 0 8 0 inpcb 280 5963 0 5954 66 64 2 13 0 8 1 rttmr 72 7 0 6 1 0 1 1 0 8 0 ip6q 72 4 0 4 2 2 0 1 0 8 0 ip6af 40 12 0 12 2 2 0 1 0 8 0 nd6 48 76 0 75 2 1 1 1 0 8 0 pkpcb 40 20 0 20 8 8 0 1 0 8 0 swfcl 56 6 0 0 1 0 1 1 0 8 0 ppxss 1128 69 0 69 25 24 1 1 0 8 1 art_heap8 4096 17 0 16 12 11 1 3 0 8 0 art_heap4 256 2555 0 2353 33 17 16 17 0 8 0 art_table 32 2572 0 2369 6 3 3 3 0 8 0 art_node 16 1069 0 1030 1 0 1 1 0 8 0 sysvmsgpl 40 21 0 8 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 1394 0 1384 1 0 1 1 0 8 0 shmpl 112 132 0 4 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 7738 0 6338 46 0 46 46 0 8 0 ffsino 240 7738 0 6338 84 0 84 84 0 8 0 nchpl 144 13524 0 13065 61 42 19 61 0 8 0 uvmvnodes 72 5926 0 0 108 0 108 108 0 8 0 vnodes 208 5926 0 0 312 0 312 312 0 8 0 namei 1024 52156 0 52156 2 1 1 1 0 8 1 vcpupl 1984 32 0 0 4 0 4 4 0 8 0 vmpool 520 46 0 14 4 1 3 3 0 8 0 scsiplug 64 6 0 6 5 5 0 1 0 8 0 scxspl 192 42756 0 42756 26 25 1 7 0 8 1 plimitpl 152 323 0 315 1 0 1 1 0 8 0 sigapl 432 4053 0 4040 2 0 2 2 0 8 0 futexpl 56 110397 0 110397 2 1 1 1 0 8 1 knotepl 112 1891 0 1872 9 8 1 3 0 8 0 kqueuepl 104 2936 0 2934 13 12 1 4 0 8 0 pipepl 112 2452 0 2433 13 12 1 2 0 8 0 fdescpl 424 4054 0 4040 2 0 2 2 0 8 0 filepl 120 40833 0 40736 57 53 4 11 0 8 1 lockfpl 104 1252 0 1251 1 0 1 1 0 8 0 lockfspl 48 450 0 449 1 0 1 1 0 8 0 sessionpl 112 41 0 31 1 0 1 1 0 8 0 pgrppl 48 87 0 77 1 0 1 1 0 8 0 ucredpl 96 10199 0 10192 1 0 1 1 0 8 0 zombiepl 144 4042 0 4042 1 0 1 1 0 8 1 processpl 864 4071 0 4042 4 0 4 4 0 8 0 procpl 632 9980 0 9941 16 12 4 5 0 8 0 sosppl 128 68 0 68 18 17 1 1 0 8 1 sockpl 384 9741 0 9721 88 85 3 21 0 8 0 mcl64k 65536 1646 0 1646 167 166 1 64 0 8 1 mcl16k 16384 52 0 52 22 21 1 1 0 8 1 mcl12k 12288 131 0 131 23 22 1 1 0 8 1 mcl9k 9216 57 0 57 23 23 0 1 0 8 0 mcl8k 8192 205 0 205 13 12 1 1 0 8 1 mcl4k 4096 435 0 435 3 2 1 1 0 8 1 mcl2k2 2112 35 0 35 19 18 1 1 0 8 1 mcl2k 2048 72567 0 72522 15 8 7 13 0 8 0 mtagpl 80 203 0 197 4 3 1 1 0 8 0 mbufpl 256 166547 0 166267 159 139 20 42 0 8 1 bufpl 256 20023 0 14452 349 0 349 349 0 8 0 anonpl 16 685696 0 664870 205 116 89 101 0 62 0 amapchunkpl 152 22367 0 22201 61 54 7 20 0 158 0 amappl16 192 35956 0 34788 199 137 62 71 0 8 1 amappl15 184 719 0 719 6 6 0 1 0 8 0 amappl14 176 575 0 569 1 0 1 1 0 8 0 amappl13 168 615 0 613 6 5 1 1 0 8 0 amappl12 160 1449 0 1446 1 0 1 1 0 8 0 amappl11 152 371 0 360 1 0 1 1 0 8 0 amappl10 144 368 0 367 2 1 1 1 0 8 0 amappl9 136 1074 0 1066 1 0 1 1 0 8 0 amappl8 128 652 0 609 2 0 2 2 0 8 0 amappl7 120 460 0 453 1 0 1 1 0 8 0 amappl6 112 311 0 298 1 0 1 1 0 8 0 amappl5 104 1795 0 1785 1 0 1 1 0 8 0 amappl4 96 3903 0 3874 1 0 1 1 0 8 0 amappl3 88 983 0 973 1 0 1 1 0 8 0 amappl2 80 31260 0 31189 3 1 2 3 0 8 0 amappl1 72 86794 0 86383 27 18 9 20 0 8 0 amappl 80 10576 0 10520 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 64 133 0 4 3 0 3 3 0 8 0 uaddrrnd 24 4100 0 4040 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 4100 0 4040 1 0 1 1 0 8 0 vmmpekpl 168 30424 0 30384 4 1 3 3 0 8 0 vmmpepl 168 513511 0 511126 476 334 142 166 0 357 30 vmsppl 272 4053 0 4040 8 7 1 2 0 8 0 pdppl 4096 8206 0 8140 13 4 9 9 0 8 0 pvpl 32 1722397 0 1700258 457 251 206 229 0 265 14 pmappl 200 4099 0 4054 5 2 3 3 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 945 0 449 17 1 16 17 0 8 0