panic: kernel diagnostic assertion "ifp != NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/netinet/if_ether.c", line 716 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 221874 8373 0 0 0x480 1 syz-executor.0 *383807 49558 0 0x14000 0x40000200 0K 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(ffffffff82206dec,ffffffff82204cd4,2cc,ffffffff8218b3d4) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd8065483af8) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff82578688) at arptimer+0x95 sys/netinet/if_ether.c:120 timeout_run(ffffffff82578688) at timeout_run+0xc4 timeout_sync_leave sys/kern/kern_timeout.c:177 [inline] timeout_run(ffffffff82578688) at timeout_run+0xc4 sys/kern/kern_timeout.c:474 softclock_thread(ffff800020a11148) at softclock_thread+0x16a sys/kern/kern_timeout.c:553 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{0}> ddb{0}> set $lines = 0 ddb{0}> set $maxwidth = 0 ddb{0}> show panic kernel diagnostic assertion "ifp != NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/netinet/if_ether.c", line 716 ddb{0}> 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(ffffffff82206dec,ffffffff82204cd4,2cc,ffffffff8218b3d4) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd8065483af8) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff82578688) at arptimer+0x95 sys/netinet/if_ether.c:120 timeout_run(ffffffff82578688) at timeout_run+0xc4 timeout_sync_leave sys/kern/kern_timeout.c:177 [inline] timeout_run(ffffffff82578688) at timeout_run+0xc4 sys/kern/kern_timeout.c:474 softclock_thread(ffff800020a11148) at softclock_thread+0x16a sys/kern/kern_timeout.c:553 end trace frame: 0x0, count: -7 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff800020a25c80 rbx 0xffff800020a25d30 rdx 0xffff800020a11148 rcx 0 rax 0 r8 0xffffffff819b183f kprintf+0x16f r9 0x1 r10 0x25 r11 0x5b4570cf5728b4c4 r12 0x3000000008 r13 0xffff800020a25c90 r14 0x100 r15 0x1 rip 0xffffffff8195ee38 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020a25c70 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (softclock) pid=383807 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=51, nice=20 forw=0xffffffffffffffff, list=0xffff800020a11638,0xffff800020a10ee0 process=0xffff800020a12000 user=0xffff800020a20000, vmspace=0xffffffff82652f08 estcpu=1, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 8373 221874 47827 0 7 0x480 syz-executor.0 8373 495118 47827 0 3 0x4000080 netcon2 syz-executor.0 8373 280297 47827 0 3 0x4000080 fsleep syz-executor.0 47827 176748 91451 0 2 0x482 syz-executor.0 66742 443887 91451 0 3 0x82 piperd syz-executor.1 67539 287068 0 0 3 0x14200 acct acct 80877 512502 0 0 3 0x14200 bored sosplice 91451 338528 72051 0 3 0x82 kqread syz-fuzzer 91451 416183 72051 0 3 0x4000082 thrsleep syz-fuzzer 91451 505549 72051 0 3 0x4000082 thrsleep syz-fuzzer 91451 466006 72051 0 3 0x4000082 thrsleep syz-fuzzer 91451 289551 72051 0 3 0x4000082 thrsleep syz-fuzzer 91451 293629 72051 0 3 0x4000082 thrsleep syz-fuzzer 91451 121171 72051 0 3 0x4000082 thrsleep syz-fuzzer 91451 23021 72051 0 3 0x4000082 thrsleep syz-fuzzer 91451 490373 72051 0 3 0x4000082 thrsleep syz-fuzzer 91451 265384 72051 0 3 0x4000082 thrsleep syz-fuzzer 72051 183511 93527 0 3 0x10008a pause ksh 93527 457252 41114 0 3 0x92 select sshd 97742 97894 1 0 3 0x100083 ttyopn getty 41114 207260 1 0 3 0x80 select sshd 99826 19598 81067 74 3 0x100092 bpf pflogd 81067 205338 1 0 3 0x80 netio pflogd 42614 18947 40692 73 3 0x100090 kqread syslogd 40692 2956 1 0 3 0x100082 netio syslogd 61710 169363 1 77 3 0x100090 poll dhclient 59095 35973 1 0 3 0x80 poll dhclient 44020 8058 0 0 3 0x14200 pgzero zerothread 65271 17568 0 0 3 0x14200 aiodoned aiodoned 62629 116926 0 0 3 0x14200 syncer update 36372 251181 0 0 3 0x14200 cleaner cleaner 70160 337171 0 0 3 0x14200 reaper reaper 27901 225494 0 0 3 0x14200 pgdaemon pagedaemon 7286 111546 0 0 3 0x14200 bored crynlk 913 238170 0 0 3 0x14200 bored crypto 7283 254990 0 0 3 0x40014200 acpi0 acpi0 66150 14956 0 0 3 0x40014200 idle1 14515 412301 0 0 3 0x14200 bored softnet 63120 409998 0 0 3 0x14200 bored systqmp 93457 505824 0 0 3 0x14200 bored systq *49558 383807 0 0 7 0x40014200 softclock 21745 61441 0 0 3 0x40014200 idle0 32221 386968 0 0 3 0x14200 bored smr 1 379776 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 49558 (softclock) thread 0xffff800020a11148 (383807) exclusive rwlock netlock r = 0 (0xffffffff82478e48) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 arptimer+0x22 sys/netinet/if_ether.c:119 #2 timeout_run+0xc4 timeout_sync_leave sys/kern/kern_timeout.c:177 [inline] #2 timeout_run+0xc4 sys/kern/kern_timeout.c:474 #3 softclock_thread+0x16a sys/kern/kern_timeout.c:553 #4 proc_trampoline+0x1c shared rwlock timeout r = 0 (0xffffffff824aeaa8) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 timeout_run+0xb9 sys/kern/kern_timeout.c:473 #2 softclock_thread+0x16a sys/kern/kern_timeout.c:553 #3 proc_trampoline+0x1c exclusive kernel_lock &kernel_lock r = 0 (0xffffffff8263e9d8) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 __mp_acquire_count+0x51 sys/kern/kern_lock.c:227 #2 mi_switch+0x392 sys/kern/sched_bsd.c:436 #3 sleep_finish+0x113 sys/kern/kern_synch.c:373 #4 softclock_thread+0x103 sys/kern/kern_timeout.c:548 #5 proc_trampoline+0x1c ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9594 6462K 8357K 78643K 17225 0 0 pcb 13 8K 8K 78643K 646 0 0 rtable 106 13K 13K 78643K 2357 0 0 ifaddr 89 20K 21K 78643K 644 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 4K 78643K 1610 0 0 iov 0 0K 32K 78643K 547 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1235 78K 78K 78643K 4545 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 46 0 0 VM map 30 15K 15K 78643K 32 0 0 sem 12 0K 0K 78643K 655 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12765 0 0 file desc 5 13K 25K 78643K 2975 0 0 sigio 0 0K 0K 78643K 43 0 0 proc 62 63K 95K 78643K 1561 0 0 subproc 32 2K 2K 78643K 374 0 0 NFS srvsock 1 0K 0K 78643K 1 0 0 NFS daemon 1 16K 16K 78643K 1 0 0 ip_moptions 0 0K 1K 78643K 335 0 0 in_multi 25 1K 2K 78643K 438 0 0 ether_multi 1 0K 0K 78643K 42 0 0 mrt 0 0K 0K 78643K 22 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 126 556K 556K 78643K 126 0 0 exec 0 0K 1K 78643K 739 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 148 250K 254K 78643K 11548 0 0 UVM aobj 130 6K 6K 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 2K 78643K 665 0 0 NDP 20 0K 0K 78643K 202 0 0 temp 230 3567K 3640K 78643K 92997 0 0 kqueue 1 0K 0K 78643K 29 0 0 SYN cache 2 16K 16K 78643K 2 0 0 ddb{0}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 93 0 87 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 236 0 234 1 0 1 1 0 8 0 rtentry 112 442 0 404 2 0 2 2 0 8 0 unpcb 120 3963 0 3949 15 13 2 3 0 8 1 syncache 264 12 0 12 6 6 0 1 0 8 0 sackhl 24 1 0 1 1 1 0 1 0 8 0 tcpqe 32 84 0 84 4 4 0 1 0 8 0 tcpcb 544 1146 0 1140 5 4 1 2 0 8 0 inpcb 280 3792 0 3782 7 6 1 2 0 8 0 rttmr 72 7 0 7 6 6 0 1 0 8 0 ip6q 72 1 0 1 1 1 0 1 0 8 0 nd6 48 67 0 65 1 0 1 1 0 8 0 pkpcb 40 26 0 26 8 8 0 1 0 8 0 ppxss 1128 89 0 89 11 10 1 1 0 8 1 pffrag 232 76 0 76 10 10 0 1 0 482 0 pffrnode 88 76 0 76 10 10 0 1 0 8 0 pffrent 40 2176 0 2176 10 10 0 1 0 8 0 pfosfp 40 846 0 423 5 0 5 5 0 8 0 pfosfpen 112 1428 0 714 21 0 21 21 0 8 0 pfstitem 24 267 0 219 1 0 1 1 0 8 0 pfstkey 112 267 0 219 3 1 2 3 0 8 0 pfstate 328 267 0 219 7 1 6 7 0 8 0 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 3 0 2 3 2 1 3 0 8 0 art_heap4 256 1918 0 1727 38 24 14 26 0 8 1 art_table 32 1921 0 1729 7 4 3 4 0 8 1 art_node 16 441 0 406 1 0 1 1 0 8 0 sysvmsgpl 40 38 0 22 2 1 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 653 0 643 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 6617 0 5198 46 0 46 46 0 8 0 ffsino 272 6617 0 5198 96 1 95 95 0 8 0 nchpl 144 12167 0 10569 61 0 61 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 46413 0 46413 1 0 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 vcpupl 1984 28 0 0 4 0 4 4 0 8 0 vmpool 552 30 0 2 2 0 2 2 0 8 0 scsiplug 64 4 0 4 4 4 0 1 0 8 0 scxspl 192 32198 0 32198 19 18 1 6 0 8 1 plimitpl 152 229 0 221 1 0 1 1 0 8 0 sigapl 432 3115 0 3100 3 1 2 3 0 8 0 futexpl 56 70146 0 70145 1 0 1 1 0 8 0 knotepl 112 794 0 774 1 0 1 1 0 8 0 kqueuepl 104 876 0 873 1 0 1 1 0 8 0 pipepl 112 3154 0 3135 9 7 2 2 0 8 0 fdescpl 488 3116 0 3100 3 0 3 3 0 8 0 filepl 152 34889 0 34783 24 18 6 9 0 8 1 lockfpl 104 994 0 993 1 0 1 1 0 8 0 lockfspl 48 341 0 340 1 0 1 1 0 8 0 sessionpl 112 38 0 27 1 0 1 1 0 8 0 pgrppl 48 65 0 54 1 0 1 1 0 8 0 ucredpl 96 9565 0 9556 1 0 1 1 0 8 0 zombiepl 144 3103 0 3103 1 0 1 1 0 8 1 processpl 896 3136 0 3103 4 0 4 4 0 8 0 procpl 632 9735 0 9691 6 1 5 5 0 8 1 srpgc 64 32 0 32 13 13 0 1 0 8 0 sosppl 128 52 0 52 11 11 0 1 0 8 0 sockpl 384 8055 0 8029 34 28 6 9 0 8 3 mcl64k 65536 34 0 0 3 0 3 3 0 8 0 mcl16k 16384 19 0 0 3 1 2 3 0 8 0 mcl12k 12288 33 0 0 2 0 2 2 0 8 0 mcl9k 9216 17 0 0 2 0 2 2 0 8 0 mcl8k 8192 17 0 0 3 1 2 3 0 8 0 mcl4k 4096 18 0 0 3 0 3 3 0 8 1 mcl2k2 2112 5 0 0 1 0 1 1 0 8 0 mcl2k 2048 161 0 0 19 0 19 19 0 8 0 mtagpl 80 59 0 0 1 0 1 1 0 8 0 mbufpl 256 612 0 0 30 0 30 30 0 8 0 bufpl 256 13837 0 6789 441 0 441 441 0 8 0 anonpl 16 407380 0 390527 150 52 98 98 0 124 11 amapchunkpl 152 23006 0 22862 50 40 10 19 0 158 3 amappl16 192 17938 0 16789 136 69 67 70 0 8 7 amappl15 184 127 0 127 1 1 0 1 0 8 0 amappl14 176 345 0 339 1 0 1 1 0 8 0 amappl13 168 941 0 938 1 0 1 1 0 8 0 amappl12 160 125 0 123 2 1 1 1 0 8 0 amappl11 152 112 0 97 1 0 1 1 0 8 0 amappl10 144 302 0 299 1 0 1 1 0 8 0 amappl9 136 1217 0 1210 1 0 1 1 0 8 0 amappl8 128 726 0 685 2 0 2 2 0 8 0 amappl7 120 422 0 414 1 0 1 1 0 8 0 amappl6 112 119 0 106 1 0 1 1 0 8 0 amappl5 104 503 0 487 1 0 1 1 0 8 0 amappl4 96 3505 0 3474 1 0 1 1 0 8 0 amappl3 88 478 0 470 1 0 1 1 0 8 0 amappl2 80 23585 0 23511 3 1 2 3 0 8 0 amappl1 72 81227 0 80802 26 16 10 20 0 8 0 amappl 80 10377 0 10321 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 3146 0 3100 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 3146 0 3100 1 0 1 1 0 8 0 vmmpekpl 168 30684 0 30646 3 0 3 3 0 8 0 vmmpepl 168 407318 0 404951 263 116 147 147 0 357 36 vmsppl 368 3115 0 3100 2 0 2 2 0 8 0 pdppl 4096 6299 0 6232 9 0 9 9 0 8 0 pvpl 32 1047357 0 1027991 348 125 223 223 0 265 37 pmappl 232 3145 0 3102 4 1 3 3 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 663 0 36 19 0 19 19 0 8 0