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 *417938 67102 0 0x14000 0x40000200 0 softclock db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff82782799) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff8280178f,ffffffff82825885,2f6,ffffffff8275080c) at __assert+0x29 sys/kern/subr_prf.c:157 arptfree(fffffd806bcaea98) at arptfree+0x131 sys/netinet/if_ether.c:758 arptimer(ffffffff82cd0a98) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82cd0a98) at timeout_run+0x8f sys/kern/kern_timeout.c:665 softclock_thread(ffff8000215e9aa0) at softclock_thread+0xc4 sys/kern/kern_timeout.c:809 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(ffffffff82782799) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff8280178f,ffffffff82825885,2f6,ffffffff8275080c) at __assert+0x29 sys/kern/subr_prf.c:157 arptfree(fffffd806bcaea98) at arptfree+0x131 sys/netinet/if_ether.c:758 arptimer(ffffffff82cd0a98) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82cd0a98) at timeout_run+0x8f sys/kern/kern_timeout.c:665 softclock_thread(ffff8000215e9aa0) at softclock_thread+0xc4 sys/kern/kern_timeout.c:809 end trace frame: 0x0, count: -7 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff8000215f6680 rbx 0 rdx 0 rcx 0 rax 0xffff8000215e9aa0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x41087c70d93d2cdf r11 0xa61186bfceabd392 r12 0 r13 0xfffffd80749b0160 r14 0 r15 0x1 rip 0xffffffff8180b1fc db_enter+0x1c cs 0x8 rflags 0x246 rsp 0xffff8000215f6670 ss 0x10 db_enter+0x1c: addq $0x8,%rsp ddb> show proc PROC (softclock) tid=417938 pid=67102 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=0xffff8000215e9ff0,0xffff8000215e9808 process=0xffff8000ffffebd0 user=0xffff8000215f1000, vmspace=0xffffffff82c965e0 estcpu=0, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 40001 435760 0 0 3 0x14200 bored sosplice 18202 504342 1226 0 3 0x82 wait syz-executor.7 4188 87952 1226 0 3 0x82 piperd syz-executor.5 59165 388770 1226 0 3 0x82 piperd syz-executor.3 99854 327849 1226 0 3 0x82 piperd syz-executor.1 35817 281691 1226 0 3 0x82 piperd syz-executor.4 1226 318045 85839 0 3 0x2000082 wait syz-fuzzer 1226 371102 85839 0 3 0x6000082 thrsleep syz-fuzzer 1226 199396 85839 0 3 0x6000082 wait syz-fuzzer 1226 149137 85839 0 3 0x6000082 wait syz-fuzzer 1226 147247 85839 0 3 0x6000082 wait syz-fuzzer 1226 354845 85839 0 3 0x6000082 thrsleep syz-fuzzer 1226 292267 85839 0 3 0x6000082 thrsleep syz-fuzzer 1226 430658 85839 0 3 0x6000082 wait syz-fuzzer 1226 214286 85839 0 3 0x6000082 thrsleep syz-fuzzer 1226 56966 85839 0 3 0x6000082 wait syz-fuzzer 1226 455868 85839 0 3 0x6000082 thrsleep syz-fuzzer 1226 204836 85839 0 3 0x6000082 kqread syz-fuzzer 1226 494879 85839 0 3 0x6000082 wait syz-fuzzer 1226 384745 85839 0 3 0x6000082 thrsleep syz-fuzzer 85839 398423 15618 0 3 0x10008a sigsusp ksh 15618 220718 36704 0 3 0x9a kqread sshd 40719 245445 1 0 3 0x100083 ttyin getty 36704 338064 1 0 3 0x88 kqread sshd 55983 61689 13865 73 3 0x1100010 biowait syslogd 13865 35195 1 0 3 0x100082 netio syslogd 81938 520225 1 0 3 0x100080 kqread resolvd 95920 138292 69727 77 3 0x100092 kqread dhcpleased 79565 157474 69727 77 3 0x100092 kqread dhcpleased 69727 235370 1 0 3 0x80 kqread dhcpleased 78225 34847 0 0 3 0x14200 bored smr 33347 150430 0 0 2 0x14200 zerothread 71664 126944 0 0 3 0x14200 aiodoned aiodoned 2210 307446 0 0 2 0x14600 update 57116 103717 0 0 3 0x14200 cleaner cleaner 57216 182553 0 0 2 0x14200 reaper 30710 411876 0 0 3 0x14200 pgdaemon pagedaemon 84440 98774 0 0 3 0x14200 bored viomb 58873 522252 0 0 3 0x40014200 acpi0 acpi0 83866 12889 0 0 3 0x14200 bored softnet3 72298 36565 0 0 3 0x14200 bored softnet2 58990 393409 0 0 3 0x14200 bored softnet1 38536 470374 0 0 3 0x14200 bored softnet0 40938 505892 0 0 2 0x14200 systqmp 17840 62675 0 0 3 0x14200 bored systq *67102 417938 0 0 7 0x40014200 softclock 34274 266062 0 0 3 0x40014200 idle0 1 87373 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 10165 6399K 7436K 78643K 12928 0 pcb 13 8K 8K 78643K 126 0 rtable 195 6K 7K 78643K 385 0 pf 25 8K 8K 78643K 29 0 ifaddr 35 10K 11K 78643K 45 0 ifgroup 42 1K 2K 78643K 50 0 counters 26 17K 17K 78643K 28 0 ioctlops 0 0K 2K 78643K 52 0 iov 0 0K 16K 78643K 45 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1294 81K 81K 78643K 1817 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 13K 78643K 23 0 VM map 2 1K 1K 78643K 2 0 sem 9 0K 0K 78643K 14 0 dirhash 12 2K 2K 78643K 24 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 8 25K 73K 78643K 1710 0 sigio 0 0K 0K 78643K 6 0 proc 58 59K 83K 78643K 532 0 subproc 78 4K 6K 78643K 104 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 157 0 in_multi 77 5K 7K 78643K 135 0 ether_multi 1 0K 0K 78643K 5 0 mrt 1 0K 0K 78643K 5 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 61 281K 281K 78643K 61 0 exec 0 0K 1K 78643K 396 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 271 76K 87K 78643K 16455 0 UVM aobj 66 3K 3K 78643K 76 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 102 0 NDP 9 0K 2K 78643K 27 0 temp 69 5911K 5988K 78643K 8263 0 kqueue 12 18K 27K 78643K 220 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 49 0 46 1 0 1 1 0 8 0 rtentry 112 116 0 27 4 0 4 4 0 8 0 unpcb 144 349 0 336 1 0 1 1 0 8 0 syncache 304 22 0 22 4 4 0 1 0 8 0 tcpqe 32 176 0 176 3 3 0 1 0 8 0 tcpcb 808 220 0 216 4 3 1 2 0 8 0 arp 88 19 0 4 1 0 1 1 0 8 0 inpcb 336 673 0 666 3 1 2 2 0 8 1 nd6 104 24 0 6 1 0 1 1 0 8 0 pkpcb 40 4 0 4 1 1 0 1 0 8 0 kcovpl 48 8 0 2 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 454 0 88 29 2 27 29 0 8 1 art_table 32 455 0 88 4 0 4 4 0 8 0 art_node 16 111 0 30 1 0 1 1 0 8 0 semupl 112 5 0 5 1 1 0 1 0 8 0 semapl 112 7 0 0 1 0 1 1 0 8 0 shmpl 112 73 0 10 2 0 2 2 0 8 0 dirhash 1024 25 0 8 3 0 3 3 0 8 0 dino2pl 256 3494 0 2053 91 0 91 91 0 8 0 ffsino 240 3494 0 2053 85 0 85 85 0 8 0 nchpl 144 5732 0 4071 63 0 63 63 0 8 0 uvmvnodes 80 4016 0 0 82 0 82 82 0 8 0 vnodes 216 4016 0 0 224 0 224 224 0 8 0 namei 1024 15279 0 15279 5 5 0 3 0 8 0 vcpupl 2048 11 0 0 2 0 2 2 0 8 0 vmpool 664 11 0 0 1 0 1 1 0 8 0 kstatmem 264 22 0 4 2 0 2 2 0 8 0 scxspl 216 19169 0 19168 11 10 1 8 1 8 0 plimitpl 152 93 0 77 1 0 1 1 0 8 0 sigapl 424 2010 0 1970 6 0 6 6 0 8 0 futexpl 64 10316 0 10316 4 4 0 1 0 8 0 knotepl 120 15646 0 15572 4 0 4 4 0 8 0 kqueuepl 184 217 0 209 1 0 1 1 0 8 0 pipepl 288 171 0 146 3 0 3 3 0 8 0 fdescpl 432 1993 0 1974 5 2 3 4 0 8 0 filepl 120 5905 0 5710 9 1 8 9 0 8 0 lockfpl 104 549 0 547 1 0 1 1 0 8 0 lockfspl 48 236 0 234 1 0 1 1 0 8 0 sessionpl 144 23 0 8 1 0 1 1 0 8 0 pgrppl 48 23 0 8 1 0 1 1 0 8 0 ucredpl 104 622 0 612 1 0 1 1 0 8 0 zombiepl 144 1975 0 1970 1 0 1 1 0 8 0 processpl 1008 2010 0 1970 6 0 6 6 0 8 0 procpl 680 3650 0 3594 6 0 6 6 0 8 0 sosppl 168 12 0 12 2 2 0 1 0 8 0 sockpl 456 1075 0 1052 10 7 3 5 0 8 0 mcl64k 65536 23 0 23 3 3 0 1 0 8 0 mcl16k 16384 13 0 13 3 3 0 1 0 8 0 mcl12k 12288 16 0 16 2 2 0 1 0 8 0 mcl9k 9216 14 0 14 4 4 0 1 0 8 0 mcl8k 8192 27 0 27 3 3 0 1 0 8 0 mcl4k 4096 81 0 81 2 2 0 1 0 8 0 mcl2k 2048 32829 0 32786 45 36 9 35 0 8 1 mtagpl 96 215 0 58 7 1 6 6 0 8 0 mbufpl 256 74924 0 74647 43 17 26 26 0 8 0 bufpl 288 7952 0 1555 458 0 458 458 0 8 0 anonpl 24 366948 0 354620 143 39 104 107 0 188 19 amapchunkpl 152 54862 0 53966 65 18 47 51 0 158 3 amappl16 200 8502 0 8307 28 17 11 24 0 8 0 amappl15 192 19 0 19 2 2 0 1 0 8 0 amappl14 184 225 0 213 2 1 1 2 0 8 0 amappl13 176 9 0 9 1 1 0 1 0 8 0 amappl12 168 2629 0 2600 3 1 2 2 0 8 0 amappl11 160 54 0 43 1 0 1 1 0 8 0 amappl10 152 25 0 16 2 1 1 1 0 8 0 amappl9 144 182 0 182 1 1 0 1 0 8 0 amappl8 136 194 0 141 2 0 2 2 0 8 0 amappl7 128 182 0 165 2 0 2 2 0 8 0 amappl6 120 244 0 237 1 0 1 1 0 8 0 amappl5 112 159 0 150 1 0 1 1 0 8 0 amappl4 104 422 0 400 2 1 1 2 0 8 0 amappl3 96 10642 0 10574 4 2 2 3 0 8 0 amappl2 88 2458 0 2393 3 1 2 3 0 8 0 amappl1 80 14671 0 14172 22 10 12 22 0 8 0 amappl 88 15918 0 15751 6 1 5 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 75 0 10 2 0 2 2 0 8 0 uaddrrnd 24 2004 0 1971 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 2004 0 1971 1 0 1 1 0 8 0 vmmpekpl 168 15846 0 15800 3 0 3 3 0 8 0 vmmpepl 168 130660 0 128899 124 36 88 112 0 357 0 vmsppl 368 2003 0 1970 4 0 4 4 0 8 0 rwobjpl 24 40093 0 34884 32 0 32 32 0 8 0 pdppl 4096 4014 0 3951 195 128 67 75 0 8 4 pvpl 32 917461 0 897829 385 130 255 360 0 265 73 pmappl 216 2003 0 1970 4 1 3 3 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 991 0 205 23 0 23 23 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(ffffffff82782799) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff8280178f,ffffffff82825885,2f6,ffffffff8275080c) at __assert+0x29 sys/kern/subr_prf.c:157 arptfree(fffffd806bcaea98) at arptfree+0x131 sys/netinet/if_ether.c:758 arptimer(ffffffff82cd0a98) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82cd0a98) at timeout_run+0x8f sys/kern/kern_timeout.c:665 softclock_thread(ffff8000215e9aa0) at softclock_thread+0xc4 sys/kern/kern_timeout.c:809 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(ffffffff82782799) at panic+0x165 sys/kern/subr_prf.c:198 __assert(ffffffff8280178f,ffffffff82825885,2f6,ffffffff8275080c) at __assert+0x29 sys/kern/subr_prf.c:157 arptfree(fffffd806bcaea98) at arptfree+0x131 sys/netinet/if_ether.c:758 arptimer(ffffffff82cd0a98) at arptimer+0x88 sys/netinet/if_ether.c:135 timeout_run(ffffffff82cd0a98) at timeout_run+0x8f sys/kern/kern_timeout.c:665 softclock_thread(ffff8000215e9aa0) at softclock_thread+0xc4 sys/kern/kern_timeout.c:809 end trace frame: 0x0, count: -7