panic: kernel diagnostic assertion "ifp != NULL" failed: file "/syzkaller/managers/main/kernel/sys/netinet/if_ether.c", line 758 Stopped at db_enter+0x1c: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *380456 95943 0 0x14000 0x40000200 0 softclock db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff82783c4b) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff827fd5c1,ffffffff828240fa,2f6,ffffffff8274cebd) at __assert+0x29 sys/kern/subr_prf.c:157 arptfree(fffffd8068541af8) at arptfree+0x131 sys/netinet/if_ether.c:758 arptimer(ffffffff82d539b0) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82d539b0) at timeout_run+0x8f sys/kern/kern_timeout.c:640 softclock_thread(ffff8000215ea540) at softclock_thread+0xd4 sys/kern/kern_timeout.c:763 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 758 ddb> trace db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff82783c4b) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff827fd5c1,ffffffff828240fa,2f6,ffffffff8274cebd) at __assert+0x29 sys/kern/subr_prf.c:157 arptfree(fffffd8068541af8) at arptfree+0x131 sys/netinet/if_ether.c:758 arptimer(ffffffff82d539b0) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82d539b0) at timeout_run+0x8f sys/kern/kern_timeout.c:640 softclock_thread(ffff8000215ea540) at softclock_thread+0xd4 sys/kern/kern_timeout.c:763 end trace frame: 0x0, count: -7 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff8000215f6200 rbx 0 rdx 0 rcx 0 rax 0xffff8000215ea540 r8 0x101010101010101 r9 0x8080808080808080 r10 0x1b9de14f365674f5 r11 0xd6dd676a05c8e1ce r12 0 r13 0xfffffd806ec34d10 r14 0 r15 0x1 rip 0xffffffff810aadfc db_enter+0x1c cs 0x8 rflags 0x246 rsp 0xffff8000215f61f0 ss 0x10 db_enter+0x1c: addq $0x8,%rsp ddb> show proc PROC (softclock) tid=380456 pid=95943 tcnt=1 stat=onproc flags process=14000 proc=40000200 runpri=50, usrpri=50, slppri=0, nice=20 wchan=0x0, wmesg=, ps_single=0x0 forw=0xffffffffffffffff, list=0xffff8000215ea7e8,0xffff8000215ea2a8 process=0xffff8000ffffe000 user=0xffff8000215f1000, vmspace=0xffffffff82cb6308 estcpu=0, cpticks=2, pctcpu=0.0, user=0, sys=2, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 12594 268220 28259 0 2 0x100000 sh 28259 154506 57014 0 3 0x10008a sigsusp sh 28140 220663 52915 0 2 0x10 syz-executor.5 28140 152171 52915 0 2 0x4000010 syz-executor.5 28140 376586 52915 0 3 0x4000090 fsleep syz-executor.5 7549 404800 97303 0 2 0 syz-executor.4 57014 438816 6729 0 3 0x82 wait syz-executor.6 44302 393562 33618 0 2 0 syz-executor.2 90412 177395 6729 0 2 0x482 syz-executor.3 62891 108081 28833 0 2 0x100002 sh 12839 246271 79038 0 2 0x100002 ndp 28833 285666 6729 0 3 0x82 wait syz-executor.7 79038 33689 38599 0 3 0x10008a sigsusp sh 52915 508253 6729 0 2 0x482 syz-executor.5 38599 345906 6729 0 3 0x82 wait syz-executor.1 97303 147514 6729 0 2 0x482 syz-executor.4 33618 5279 6729 0 2 0x482 syz-executor.2 12215 417916 0 0 3 0x14280 nfsidl nfsio 78463 488468 0 0 3 0x14280 nfsidl nfsio 82752 319494 0 0 3 0x14280 nfsidl nfsio 35562 456542 0 0 3 0x14280 nfsidl nfsio 33284 398180 0 0 3 0x14280 nfsidl nfsio 28521 208030 0 0 3 0x14280 nfsidl nfsio 42625 495983 0 0 3 0x14280 nfsidl nfsio 52423 412473 0 0 3 0x14280 nfsidl nfsio 99933 466372 0 0 3 0x14280 nfsidl nfsio 81297 266768 0 0 3 0x14280 nfsidl nfsio 28170 141025 0 0 3 0x14280 nfsidl nfsio 39103 33603 0 0 3 0x14280 nfsidl nfsio 15929 136091 0 0 3 0x14280 nfsidl nfsio 43027 44990 0 0 3 0x14280 nfsidl nfsio 63950 301040 0 0 3 0x14280 nfsidl nfsio 13019 424780 0 0 3 0x14280 nfsidl nfsio 86002 184394 0 0 3 0x14280 nfsidl nfsio 44671 429283 0 0 3 0x14280 nfsidl nfsio 82444 307047 0 0 3 0x14280 nfsidl nfsio 88768 476745 0 0 3 0x14280 nfsidl nfsio 31226 148492 0 0 2 0x14600 acct 33869 178211 0 0 3 0x14200 bored sosplice 6729 254886 73853 0 3 0x2000082 thrsleep syz-fuzzer 6729 125044 73853 0 2 0x6000482 syz-fuzzer 6729 301036 73853 0 3 0x6000082 wait syz-fuzzer 6729 219677 73853 0 3 0x6000082 thrsleep syz-fuzzer 6729 129159 73853 0 3 0x6000082 wait syz-fuzzer 6729 270269 73853 0 3 0x6000082 wait syz-fuzzer 6729 45458 73853 0 2 0x6000482 syz-fuzzer 6729 297396 73853 0 3 0x6000082 thrsleep syz-fuzzer 6729 199418 73853 0 3 0x6000082 wait syz-fuzzer 6729 378909 73853 0 3 0x6000082 wait syz-fuzzer 6729 370672 73853 0 3 0x6000082 thrsleep syz-fuzzer 6729 297316 73853 0 3 0x6000082 wait syz-fuzzer 6729 172660 73853 0 3 0x6000082 wait syz-fuzzer 6729 201788 73853 0 3 0x6000082 wait syz-fuzzer 73853 381653 7391 0 3 0x10008a sigsusp ksh 7391 27511 51390 0 3 0x9a kqread sshd 61400 342725 1 0 3 0x100083 ttyin getty 51390 253194 1 0 3 0x88 kqread sshd 50161 287317 53501 73 3 0x1100010 ffs_fsync syslogd 53501 99951 1 0 3 0x100082 netio syslogd 36114 145084 1 0 3 0x100080 kqread resolvd 27778 85232 41173 77 3 0x100092 kqread dhcpleased 45471 25222 41173 77 3 0x100092 kqread dhcpleased 41173 133486 1 0 3 0x80 kqread dhcpleased 82514 375723 0 0 3 0x14200 bored smr 4799 247009 0 0 2 0x14200 zerothread 39578 143900 0 0 3 0x14200 aiodoned aiodoned 45970 351370 0 0 2 0x14600 update 71654 523118 0 0 3 0x14200 cleaner cleaner 97096 504469 0 0 2 0x14200 reaper 83883 326901 0 0 3 0x14200 pgdaemon pagedaemon 12379 293260 0 0 3 0x14200 bored viomb 11548 297780 0 0 3 0x40014200 acpi0 acpi0 91657 80359 0 0 3 0x14200 bored softnet3 27472 184419 0 0 3 0x14200 bored softnet2 16505 240052 0 0 3 0x14200 bored softnet1 10968 524276 0 0 3 0x14200 bored softnet0 2296 196995 0 0 2 0x14200 systqmp 35113 467008 0 0 3 0x14200 bored systq *95943 380456 0 0 7 0x40014200 softclock 19143 328425 0 0 3 0x40014200 idle0 1 378965 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 10176 6419K 7180K 78643K 16106 0 pcb 13 13K 14K 78643K 125 0 rtable 213 6K 7K 78643K 724 0 pf 27 8K 9K 78643K 158 0 ifaddr 39 11K 12K 78643K 134 0 ifgroup 46 2K 2K 78643K 261 0 sysctl 2 0K 0K 78643K 4 0 counters 27 17K 17K 78643K 84 0 ioctlops 0 0K 2K 78643K 155 0 iov 0 0K 16K 78643K 429 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1479 92K 93K 78643K 3656 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 44 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 1K 78643K 1555 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 18 65K 73K 78643K 3057 0 sigio 0 0K 0K 78643K 100 0 proc 57 59K 75K 78643K 863 0 subproc 104 6K 6K 78643K 234 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 70 0 in_multi 88 6K 7K 78643K 216 0 ether_multi 1 0K 0K 78643K 4 0 mrt 0 0K 0K 78643K 3 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 91 413K 413K 78643K 91 0 exec 0 0K 1K 78643K 1065 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 339 91K 92K 78643K 30272 0 UVM aobj 131 4K 4K 78643K 137 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 40 0 NDP 10 0K 2K 78643K 101 0 temp 74 5912K 5992K 78643K 29061 0 kqueue 12 18K 31K 78643K 250 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 120 188 0 184 3 2 1 2 0 8 0 rtentry 112 213 0 115 4 0 4 4 0 8 1 unpcb 144 4261 0 4246 37 35 2 10 0 8 1 syncache 304 22 0 22 5 5 0 1 0 8 0 tcpqe 32 137 0 137 4 4 0 1 0 8 0 tcpcb 808 467 0 463 19 18 1 7 0 8 0 arp 88 37 0 20 1 0 1 1 0 8 0 inpcb 336 2058 0 2051 45 44 1 13 0 8 0 nd6 104 53 0 34 1 0 1 1 0 8 0 pkpcb 40 3 0 3 1 1 0 1 0 8 0 kcovpl 48 18 0 10 1 0 1 1 0 8 0 ppxss 1160 15 0 15 4 4 0 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 870 0 454 30 2 28 30 0 8 2 art_table 32 871 0 454 4 0 4 4 0 8 0 art_node 16 212 0 123 1 0 1 1 0 8 0 sysvmsgpl 40 11 0 3 1 0 1 1 0 8 0 semupl 112 4 0 4 1 1 0 1 0 8 0 semapl 112 1553 0 1543 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 dino2pl 256 5550 0 4111 91 0 91 91 0 8 0 ffsino 240 5550 0 4111 86 0 86 86 0 8 0 nchpl 144 9600 0 7955 63 0 63 63 0 8 1 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 34825 0 34825 4 3 1 3 0 8 1 kstatmem 264 134 0 114 2 0 2 2 0 8 0 scxspl 216 30547 0 30546 13 12 1 8 1 8 0 plimitpl 152 430 0 414 1 0 1 1 0 8 0 sigapl 424 3354 0 3286 8 0 8 8 0 8 0 futexpl 64 36621 0 36620 2 1 1 1 0 8 0 knotepl 120 28229 0 28145 4 1 3 4 0 8 0 kqueuepl 184 2139 0 2131 30 29 1 7 0 8 0 pipepl 288 872 0 845 28 25 3 14 0 8 1 fdescpl 432 3316 0 3287 4 0 4 4 0 8 0 filepl 120 24084 0 23850 63 55 8 19 0 8 0 lockfpl 104 1477 0 1475 5 4 1 3 0 8 0 lockfspl 48 712 0 710 2 1 1 2 0 8 0 sessionpl 144 33 0 17 1 0 1 1 0 8 0 pgrppl 48 44 0 28 1 0 1 1 0 8 0 ucredpl 104 4233 0 4222 1 0 1 1 0 8 0 zombiepl 144 3288 0 3286 1 0 1 1 0 8 0 processpl 1008 3354 0 3286 10 1 9 9 0 8 0 procpl 680 8061 0 7978 10 1 9 9 0 8 0 sosppl 168 147 0 147 6 6 0 1 0 8 0 sockpl 456 6528 0 6502 171 166 5 33 0 8 1 mcl64k 65536 104 0 104 7 7 0 1 0 8 0 mcl16k 16384 47 0 47 7 7 0 1 0 8 0 mcl12k 12288 95 0 95 8 7 1 1 0 8 1 mcl9k 9216 54 0 54 10 10 0 1 0 8 0 mcl8k 8192 189 0 189 5 5 0 1 0 8 0 mcl4k 4096 694 0 694 4 3 1 2 0 8 1 mcl2k2 2112 22 0 22 8 8 0 1 0 8 0 mcl2k 2048 70985 0 70920 46 37 9 29 0 8 0 mtagpl 96 1157 0 1157 20 2 18 18 0 8 18 mbufpl 256 138423 0 138213 238 215 23 99 0 8 8 bufpl 288 9512 0 3114 458 0 458 458 0 8 0 anonpl 24 426958 0 410879 145 33 112 112 0 188 15 amapchunkpl 152 95755 0 94721 58 12 46 47 0 158 6 amappl16 200 9368 0 8980 47 24 23 35 0 8 1 amappl15 192 15 0 15 3 3 0 1 0 8 0 amappl14 184 179 0 165 2 1 1 2 0 8 0 amappl13 176 14 0 14 2 2 0 1 0 8 0 amappl12 168 4099 0 4067 2 0 2 2 0 8 0 amappl11 160 53 0 43 1 0 1 1 0 8 0 amappl10 152 35 0 25 2 1 1 1 0 8 0 amappl9 144 183 0 182 2 1 1 1 0 8 0 amappl8 136 265 0 192 3 0 3 3 0 8 0 amappl7 128 62 0 49 2 0 2 2 0 8 0 amappl6 120 314 0 287 2 1 1 2 0 8 0 amappl5 112 245 0 237 1 0 1 1 0 8 0 amappl4 104 590 0 551 2 0 2 2 0 8 0 amappl3 96 19553 0 19477 3 0 3 3 0 8 1 amappl2 88 3589 0 3529 3 1 2 3 0 8 0 amappl1 80 20945 0 20410 22 10 12 22 0 8 0 amappl 88 29619 0 29408 6 0 6 6 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 72 136 0 6 3 0 3 3 0 8 0 uaddrrnd 24 3316 0 3287 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 3316 0 3287 1 0 1 1 0 8 0 vmmpekpl 168 29585 0 29531 3 0 3 3 0 8 0 vmmpepl 168 215523 0 213320 181 62 119 119 0 357 19 vmsppl 368 3315 0 3286 3 0 3 3 0 8 0 rwobjpl 24 62211 0 54708 46 0 46 46 0 8 0 pdppl 4096 6638 0 6572 252 186 66 68 0 8 0 pvpl 32 1076466 0 1052199 400 176 224 330 0 265 26 pmappl 216 3315 0 3286 2 0 2 2 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 1340 0 555 25 0 25 25 0 8 0 ddb> machine ddbcpu 0 No such command ddb> trace db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff82783c4b) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff827fd5c1,ffffffff828240fa,2f6,ffffffff8274cebd) at __assert+0x29 sys/kern/subr_prf.c:157 arptfree(fffffd8068541af8) at arptfree+0x131 sys/netinet/if_ether.c:758 arptimer(ffffffff82d539b0) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82d539b0) at timeout_run+0x8f sys/kern/kern_timeout.c:640 softclock_thread(ffff8000215ea540) at softclock_thread+0xd4 sys/kern/kern_timeout.c:763 end trace frame: 0x0, count: -7 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff82783c4b) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff827fd5c1,ffffffff828240fa,2f6,ffffffff8274cebd) at __assert+0x29 sys/kern/subr_prf.c:157 arptfree(fffffd8068541af8) at arptfree+0x131 sys/netinet/if_ether.c:758 arptimer(ffffffff82d539b0) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82d539b0) at timeout_run+0x8f sys/kern/kern_timeout.c:640 softclock_thread(ffff8000215ea540) at softclock_thread+0xd4 sys/kern/kern_timeout.c:763 end trace frame: 0x0, count: -7