panic: kernel diagnostic assertion "ifp != NULL" failed: file "/syzkaller/managers/main/kernel/sys/netinet/if_ether.c", line 776 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND * 76651 91823 0 0x14000 0x40000200 0 softclock db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff827255cd) at panic+0x161 sys/kern/subr_prf.c:198 __assert(ffffffff8279e803,ffffffff827c1cb2,308,ffffffff826f0255) at __assert+0x25 sys/kern/subr_prf.c:157 arptfree(fffffd8069c1a7f8) at arptfree+0x12d sys/netinet/if_ether.c:776 arptimer(ffffffff82caa9f8) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82caa9f8) at timeout_run+0x8b sys/kern/kern_timeout.c:641 softclock_thread(ffff8000ffffed98) at softclock_thread+0xf4 sys/kern/kern_timeout.c:765 end trace frame: 0x0, count: 8 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 *cpu0: kernel diagnostic assertion "ifp != NULL" failed: file "/syzkaller/managers/main/kernel/sys/netinet/if_ether.c", line 776 ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff827255cd) at panic+0x161 sys/kern/subr_prf.c:198 __assert(ffffffff8279e803,ffffffff827c1cb2,308,ffffffff826f0255) at __assert+0x25 sys/kern/subr_prf.c:157 arptfree(fffffd8069c1a7f8) at arptfree+0x12d sys/netinet/if_ether.c:776 arptimer(ffffffff82caa9f8) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82caa9f8) at timeout_run+0x8b sys/kern/kern_timeout.c:641 softclock_thread(ffff8000ffffed98) at softclock_thread+0xf4 sys/kern/kern_timeout.c:765 end trace frame: 0x0, count: -7 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff800021604c50 rbx 0 rdx 0 rcx 0 rax 0xffff8000ffffed98 r8 0x101010101010101 r9 0x8080808080808080 r10 0x3e0b8daab445e7c2 r11 0x2be93f47e904ffe5 r12 0 r13 0xfffffd8074c4f5d8 r14 0 r15 0x1 rip 0xffffffff81383b58 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800021604c40 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (softclock) pid=76651 stat=onproc flags process=14000 proc=40000200 pri=50, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff8000fffff5c0,0xffff8000ffffeaf0 process=0xffff8000ffffc7e0 user=0xffff8000215ff000, vmspace=0xffffffff82caa8b8 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 5752 353744 35781 0 2 0 syz-executor.4 27441 375818 29409 0 2 0 syz-executor.6 40281 209415 95110 0 2 0 syz-executor.2 40281 161919 95110 0 3 0x4000080 fsleep syz-executor.2 87511 351005 73249 0 2 0 syz-executor.3 87511 156304 73249 0 2 0x4000000 syz-executor.3 7691 435102 15973 0 2 0 syz-executor.0 7691 205007 15973 0 3 0x4000080 fsleep syz-executor.0 65270 35561 54915 0 2 0 syz-executor.5 65270 105932 54915 0 3 0x4000080 bpf syz-executor.5 65270 2909 54915 0 3 0x4000000 smrbar syz-executor.5 15973 207262 76992 0 2 0x482 syz-executor.0 29409 337777 76992 0 2 0x482 syz-executor.6 73249 351635 76992 0 2 0x482 syz-executor.3 35781 273042 76992 0 2 0x482 syz-executor.4 35850 504180 76992 0 2 0x2 syz-executor.7 88598 68448 76992 0 2 0x2 syz-executor.1 95110 394212 76992 0 2 0x482 syz-executor.2 6957 314559 1 0 3 0x100083 ttyin getty 54915 219560 76992 0 2 0x482 syz-executor.5 10372 120954 0 0 3 0x14200 acct acct 54595 363084 0 0 3 0x14200 bored sosplice 76992 43220 69714 0 3 0x82 wait syz-fuzzer 76992 507021 69714 0 3 0x4000082 nanoslp syz-fuzzer 76992 404457 69714 0 3 0x4000082 wait syz-fuzzer 76992 334749 69714 0 3 0x4000082 thrsleep syz-fuzzer 76992 521110 69714 0 3 0x4000082 thrsleep syz-fuzzer 76992 378573 69714 0 3 0x4000082 wait syz-fuzzer 76992 122363 69714 0 3 0x4000082 wait syz-fuzzer 76992 395981 69714 0 3 0x4000082 thrsleep syz-fuzzer 76992 33022 69714 0 2 0x4000482 syz-fuzzer 76992 117479 69714 0 3 0x4000082 thrsleep syz-fuzzer 76992 341230 69714 0 3 0x4000082 wait syz-fuzzer 76992 431046 69714 0 3 0x4000082 wait syz-fuzzer 76992 488813 69714 0 3 0x4000082 wait syz-fuzzer 76992 461730 69714 0 3 0x4000082 wait syz-fuzzer 69714 506237 84586 0 3 0x10008a sigsusp ksh 84586 411419 59530 0 3 0x9a kqread sshd 59530 122596 1 0 3 0x88 kqread sshd 99218 392293 75833 73 3 0x1100090 kqread syslogd 75833 434880 1 0 3 0x100082 netio syslogd 27401 126067 1 0 3 0x100080 kqread resolvd 38505 496537 2069 77 3 0x100092 kqread dhcpleased 60987 401402 2069 77 2 0x100492 dhcpleased 2069 314488 1 0 3 0x80 kqread dhcpleased 11920 157009 0 0 3 0x14200 bored smr 4074 454598 0 0 2 0x14200 zerothread 51465 477400 0 0 3 0x14200 aiodoned aiodoned 19781 406879 0 0 2 0x14600 update 95886 393412 0 0 3 0x14200 cleaner cleaner 91934 143849 0 0 3 0x14200 reaper reaper 13831 246274 0 0 3 0x14200 pgdaemon pagedaemon 70145 257348 0 0 3 0x14200 bored viomb 90966 350305 0 0 3 0x40014200 acpi0 acpi0 1889 23450 0 0 3 0x14200 bored softnet 49083 120807 0 0 3 0x14200 bored softnet 73624 469704 0 0 3 0x14200 bored softnet 96077 213218 0 0 3 0x14200 bored softnet 30809 492642 0 0 2 0x14200 systqmp 53351 76895 0 0 3 0x14200 bored systq *91823 76651 0 0 7 0x40014200 softclock 11692 382547 0 0 3 0x40014200 idle0 1 480509 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 devbuf 10227 6513K 9417K 78643K 36057 0 pcb 15 20K 23K 78643K 3357 0 rtable 181 16K 18K 78643K 3829 0 ifaddr 65 22K 27K 78643K 1347 0 sysctl 3 1K 3K 78643K 11 0 counters 25 17K 17K 78643K 526 0 ioctlops 0 0K 4K 78643K 1901 0 iov 0 0K 32K 78643K 2919 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1711 107K 108K 78643K 18106 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 143 0 VM map 2 0K 0K 78643K 2 0 sem 18 1K 1K 78643K 117 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 16 57K 77K 78643K 15447 0 sigio 0 0K 0K 78643K 671 0 proc 67 59K 83K 78643K 3175 0 subproc 104 6K 7K 78643K 1083 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 1381 0 in_multi 60 4K 6K 78643K 1267 0 ether_multi 1 0K 0K 78643K 106 0 mrt 1 0K 0K 78643K 74 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 169 758K 758K 78643K 169 0 exec 0 0K 1K 78643K 4919 0 pfkey data 0 0K 0K 78643K 73 0 tdb 3 0K 0K 78643K 3 0 pagedep 1 8K 8K 78643K 1 0 inodedep 1 32K 32K 78643K 1 0 newblk 1 0K 0K 78643K 1 0 VM swap 8 62K 64K 78643K 10 0 UVM amap 341 90K 4558K 78643K 100346 0 UVM aobj 131 4K 4K 78643K 142 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 481 0 NDP 11 0K 1K 78643K 471 0 temp 124 5770K 6794K 78643K 204417 0 kqueue 12 18K 26K 78643K 1188 0 SYN cache 2 16K 16K 78643K 2 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle rtpcb 120 1348 0 1345 13 12 1 4 0 8 0 rtentry 112 1299 0 1228 4 1 3 4 0 8 0 unpcb 144 46236 0 46213 222 216 6 14 0 8 4 syncache 296 74 0 74 15 15 0 1 0 8 0 tcpqe 32 196 0 196 10 10 0 1 0 8 0 tcpcb 776 5029 0 5025 175 168 7 14 0 8 6 arp 88 179 0 164 1 0 1 1 0 8 0 ipq 40 37 0 37 3 3 0 1 0 8 0 ipqe 40 139 0 139 3 3 0 1 0 8 0 inpcb 336 17909 0 17900 309 302 7 18 0 8 6 nd6 48 272 0 259 1 0 1 1 0 8 0 pkpcb 40 20 0 20 5 5 0 1 0 8 0 kcovpl 48 83 0 75 1 0 1 1 0 8 0 mppekey 1024 86 0 86 8 8 0 1 0 8 0 ppxss 1160 317 0 317 30 30 0 1 0 8 0 pppxif 1360 168 0 168 23 23 0 1 0 8 0 pfanchor 1280 40 0 0 4 0 4 4 0 8 0 rttmr 136 10 0 10 3 3 0 1 0 8 0 art_heap8 4096 6 0 5 5 4 1 2 0 8 0 art_heap4 256 5606 0 5318 65 38 27 29 0 8 0 art_table 32 5612 0 5323 4 0 4 4 0 8 0 art_node 16 1175 0 1116 1 0 1 1 0 8 0 semupl 112 7 0 7 2 2 0 1 0 8 0 semapl 112 111 0 95 1 0 1 1 0 8 0 shmpl 112 139 0 11 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 25620 0 24124 94 0 94 94 0 8 0 ffsino 240 25620 0 24124 89 0 89 89 0 8 0 nchpl 144 47649 0 46011 63 0 63 63 0 8 0 rtmask 32 6 0 6 3 3 0 1 0 8 0 uvmvnodes 80 5926 0 0 121 0 121 121 0 8 0 vnodes 216 5926 0 0 330 0 330 330 0 8 0 namei 1024 187736 0 187736 10 9 1 2 0 8 1 vmpool 664 44 0 44 7 7 0 1 0 8 0 kstatmem 264 580 0 558 6 3 3 3 0 8 0 scsiplug 72 13 0 13 5 5 0 1 0 8 0 scxspl 216 120265 0 120265 33 32 1 8 0 8 1 plimitpl 152 2002 0 1987 1 0 1 1 0 8 0 sigapl 424 15667 0 15622 8 1 7 8 0 8 0 futexpl 64 184177 0 184175 4 3 1 1 0 8 0 knotepl 120 244488 0 244407 90 85 5 11 0 8 0 kqueuepl 184 2759 0 2750 33 32 1 4 0 8 0 pipepl 288 3444 0 3416 72 65 7 7 0 8 4 fdescpl 432 15568 0 15541 4 0 4 4 0 8 0 filepl 120 165270 0 165018 218 204 14 21 0 8 5 lockfpl 104 8833 0 8831 10 9 1 2 0 8 0 lockfspl 48 2406 0 2404 1 0 1 1 0 8 0 sessionpl 144 103 0 87 1 0 1 1 0 8 0 pgrppl 48 224 0 208 1 0 1 1 0 8 0 ucredpl 104 17249 0 17237 1 0 1 1 0 8 0 zombiepl 144 15622 0 15622 1 0 1 1 0 8 1 processpl 1008 15667 0 15622 11 4 7 9 0 8 0 procpl 696 39896 0 39833 17 8 9 10 0 8 0 sosppl 168 186 0 186 28 28 0 1 0 8 0 sockpl 456 65534 0 65499 1893 1880 13 53 0 8 7 mcl64k 65536 1218 0 1218 24 23 1 1 0 8 1 mcl16k 16384 423 0 423 39 38 1 1 0 8 1 mcl12k 12288 689 0 689 34 33 1 1 0 8 1 mcl9k 9216 136 0 136 42 42 0 1 0 8 0 mcl8k 8192 1195 0 1195 29 28 1 1 0 8 1 mcl4k 4096 2510 0 2510 18 17 1 1 0 8 1 mcl2k2 2112 118 0 118 47 46 1 1 0 8 1 mcl2k 2048 112036 0 111953 72 59 13 28 0 8 0 mtagpl 96 2118 0 1857 29 21 8 9 0 8 0 mbufpl 256 370129 0 369686 1097 1059 38 90 0 8 1 bufpl 288 27056 0 20662 457 0 457 457 0 8 0 anonpl 24 2991283 0 2974546 321 205 116 151 0 188 0 amapchunkpl 152 678720 0 678043 4469 4436 33 4420 0 158 0 amappl16 200 28632 0 28041 179 146 33 55 0 8 0 amappl15 192 103 0 102 1 0 1 1 0 8 0 amappl14 184 443 0 430 2 0 2 2 0 8 0 amappl13 176 10 0 10 2 2 0 1 0 8 0 amappl12 168 1335 0 1329 1 0 1 1 0 8 0 amappl11 160 53 0 42 1 0 1 1 0 8 0 amappl10 152 113 0 104 1 0 1 1 0 8 0 amappl9 144 1129 0 1128 2 1 1 1 0 8 0 amappl8 136 644 0 548 8 4 4 4 0 8 0 amappl7 128 341 0 316 2 1 1 2 0 8 0 amappl6 120 651 0 633 1 0 1 1 0 8 0 amappl5 112 769 0 763 1 0 1 1 0 8 0 amappl4 104 1547 0 1517 2 1 1 2 0 8 0 amappl3 96 44161 0 44112 2 0 2 2 0 8 0 amappl2 88 17036 0 16967 3 1 2 3 0 8 0 amappl1 80 348683 0 347991 29 13 16 22 0 8 0 amappl 88 98820 0 98647 5 0 5 5 0 92 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma1024 1024 1 0 0 1 0 1 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 18 0 17 1 0 1 1 0 8 0 aobjpl 72 141 0 11 3 0 3 3 0 8 0 uaddrrnd 24 15612 0 15585 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 15612 0 15585 1 0 1 1 0 8 0 vmmpekpl 168 117167 0 117112 3 0 3 3 0 8 0 vmmpepl 168 1434498 0 1431788 497 362 135 157 0 357 1 vmsppl 272 15611 0 15585 4 2 2 3 0 8 0 rwobjpl 24 367756 0 359997 55 7 48 49 0 8 0 pdppl 4096 31230 0 31170 1018 954 64 70 0 8 4 pvpl 32 5777611 0 5755540 613 407 206 269 0 265 10 pmappl 216 15611 0 15585 2 0 2 2 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 3439 0 2631 25 0 25 25 0 8 0 ddb> machine ddbcpu 0 No such command ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff827255cd) at panic+0x161 sys/kern/subr_prf.c:198 __assert(ffffffff8279e803,ffffffff827c1cb2,308,ffffffff826f0255) at __assert+0x25 sys/kern/subr_prf.c:157 arptfree(fffffd8069c1a7f8) at arptfree+0x12d sys/netinet/if_ether.c:776 arptimer(ffffffff82caa9f8) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82caa9f8) at timeout_run+0x8b sys/kern/kern_timeout.c:641 softclock_thread(ffff8000ffffed98) at softclock_thread+0xf4 sys/kern/kern_timeout.c:765 end trace frame: 0x0, count: -7 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff827255cd) at panic+0x161 sys/kern/subr_prf.c:198 __assert(ffffffff8279e803,ffffffff827c1cb2,308,ffffffff826f0255) at __assert+0x25 sys/kern/subr_prf.c:157 arptfree(fffffd8069c1a7f8) at arptfree+0x12d sys/netinet/if_ether.c:776 arptimer(ffffffff82caa9f8) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82caa9f8) at timeout_run+0x8b sys/kern/kern_timeout.c:641 softclock_thread(ffff8000ffffed98) at softclock_thread+0xf4 sys/kern/kern_timeout.c:765 end trace frame: 0x0, count: -7