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 512525 85659 0 0 0 1 syz-executor.0 *421625 85760 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(ffffffff82207803,ffffffff82203ff7,2cc,ffffffff8218c680) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd80654007e8) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff82525c78) at arptimer+0x95 sys/netinet/if_ether.c:120 timeout_run(ffffffff82525c78) at timeout_run+0xc4 timeout_sync_leave sys/kern/kern_timeout.c:177 [inline] timeout_run(ffffffff82525c78) at timeout_run+0xc4 sys/kern/kern_timeout.c:474 softclock_thread(ffff800020a109e0) 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(ffffffff82207803,ffffffff82203ff7,2cc,ffffffff8218c680) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd80654007e8) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff82525c78) at arptimer+0x95 sys/netinet/if_ether.c:120 timeout_run(ffffffff82525c78) at timeout_run+0xc4 timeout_sync_leave sys/kern/kern_timeout.c:177 [inline] timeout_run(ffffffff82525c78) at timeout_run+0xc4 sys/kern/kern_timeout.c:474 softclock_thread(ffff800020a109e0) 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 0xffff800020a25820 rbx 0xffff800020a258d0 rdx 0xffff800020a109e0 rcx 0 rax 0 r8 0xffffffff81918aaf kprintf+0x16f r9 0x1 r10 0x25 r11 0x7213e19773eadf9c r12 0x3000000008 r13 0xffff800020a25830 r14 0x100 r15 0x1 rip 0xffffffff814a9118 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020a25810 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (softclock) pid=421625 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff800020a10ed0,0xffff800020a10288 process=0xffff800020a12380 user=0xffff800020a20000, vmspace=0xffffffff8264e768 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 85659 512525 39945 0 7 0 syz-executor.0 85659 104224 39945 0 3 0x4000080 wsevent_read syz-executor.0 85659 30966 39945 0 3 0x4000080 fsleep syz-executor.0 2344 150828 2328 0 3 0x82 piperd syz-executor.1 9500 153556 1 0 3 0x100083 ttyin getty 39945 208005 2328 0 2 0x482 syz-executor.0 33018 19466 0 0 3 0x14200 acct acct 59687 366248 0 0 3 0x14200 bored sosplice 2328 489473 41971 0 3 0x82 thrsleep syz-fuzzer 2328 495556 41971 0 3 0x4000082 thrsleep syz-fuzzer 2328 21059 41971 0 3 0x4000082 thrsleep syz-fuzzer 2328 114192 41971 0 3 0x4000082 thrsleep syz-fuzzer 2328 465036 41971 0 3 0x4000082 thrsleep syz-fuzzer 2328 93275 41971 0 3 0x4000082 thrsleep syz-fuzzer 2328 476303 41971 0 3 0x4000082 thrsleep syz-fuzzer 2328 22303 41971 0 3 0x4000082 kqread syz-fuzzer 2328 103486 41971 0 3 0x4000082 thrsleep syz-fuzzer 2328 507462 41971 0 3 0x4000082 thrsleep syz-fuzzer 41971 149936 55803 0 3 0x10008a pause ksh 55803 3988 13740 0 3 0x92 select sshd 13740 80071 1 0 3 0x80 select sshd 59259 372303 47160 74 3 0x100092 bpf pflogd 47160 475225 1 0 3 0x80 netio pflogd 77287 290189 30784 73 3 0x100090 kqread syslogd 30784 473559 1 0 3 0x100082 netio syslogd 32017 338995 0 0 3 0x14200 pgzero zerothread 79069 111699 0 0 3 0x14200 aiodoned aiodoned 90407 78599 0 0 3 0x14200 syncer update 64530 173760 0 0 3 0x14200 cleaner cleaner 63262 139015 0 0 3 0x14200 reaper reaper 61803 426484 0 0 3 0x14200 pgdaemon pagedaemon 77351 351753 0 0 3 0x14200 bored crynlk 30592 20574 0 0 3 0x14200 bored crypto 90675 140383 0 0 3 0x40014200 acpi0 acpi0 36162 449166 0 0 3 0x40014200 idle1 51935 249095 0 0 3 0x14200 bored softnet 14370 460788 0 0 3 0x14200 bored systqmp 74981 359583 0 0 3 0x14200 bored systq *85760 421625 0 0 7 0x40014200 softclock 19014 66177 0 0 3 0x40014200 idle0 35066 165172 0 0 3 0x14200 bored smr 1 308418 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 85760 (softclock) thread 0xffff800020a109e0 (421625) exclusive rwlock netlock r = 0 (0xffffffff824ca238) #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 (0xffffffff824b5210) #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 (0xffffffff82625ee0) #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 9610 7042K 8812K 78643K 33200 0 0 pcb 13 12K 14K 78643K 1025 0 0 rtable 108 13K 15K 78643K 1468 0 0 ifaddr 93 20K 22K 78643K 872 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 4K 78643K 1649 0 0 iov 0 0K 28K 78643K 948 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1224 77K 78K 78643K 7785 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 57 0 0 VM map 41 20K 20K 78643K 55 0 0 sem 12 0K 0K 78643K 872 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12765 0 0 file desc 5 13K 25K 78643K 3922 0 0 sigio 0 0K 0K 78643K 30 0 0 proc 57 51K 95K 78643K 1822 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 1K 78643K 409 0 0 in_multi 26 1K 2K 78643K 448 0 0 ether_multi 1 0K 0K 78643K 44 0 0 mrt 1 0K 0K 78643K 24 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 935 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 176 348K 357K 78643K 14815 0 0 UVM aobj 130 8K 8K 78643K 138 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 1037 0 0 NDP 22 0K 1K 78643K 263 0 0 temp 244 3565K 4205K 78643K 52487 0 0 kqueue 0 0K 0K 78643K 31 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 75 0 70 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 327 0 327 3 3 0 1 0 8 0 rtentry 112 377 0 341 2 0 2 2 0 8 0 unpcb 120 2595 0 2584 5 3 2 2 0 8 1 syncache 264 22 0 22 11 10 1 1 0 8 1 tcpqe 32 31 0 31 6 6 0 1 0 8 0 tcpcb 544 2415 0 2410 30 28 2 13 0 8 1 inpcb 280 6534 0 6529 66 57 9 13 0 8 8 rttmr 72 6 0 5 3 2 1 1 0 8 0 ip6q 72 2 0 2 1 1 0 1 0 8 0 ip6af 40 6 0 6 1 1 0 1 0 8 0 nd6 48 64 0 61 2 1 1 1 0 8 0 pkpcb 40 23 0 23 8 8 0 1 0 8 0 ppxss 1128 134 0 134 13 12 1 1 0 8 1 pffrag 232 116 0 116 13 13 0 1 0 482 0 pffrnode 88 116 0 116 13 13 0 1 0 8 0 pffrent 40 2922 0 2922 13 13 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 24 292 0 258 1 0 1 1 0 8 0 pfstkey 112 294 0 260 3 1 2 2 0 8 0 pfstate 328 294 0 259 11 6 5 6 0 8 1 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 4 0 3 4 3 1 3 0 8 0 art_heap4 256 1696 0 1479 23 9 14 18 0 8 0 art_table 32 1700 0 1482 4 2 2 3 0 8 0 art_node 16 374 0 341 1 0 1 1 0 8 0 sysvmsgpl 40 46 0 32 1 0 1 1 0 8 0 semapl 112 870 0 860 1 0 1 1 0 8 0 shmpl 112 136 0 8 5 1 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 7501 0 6092 46 0 46 46 0 8 0 ffsino 272 7501 0 6092 95 0 95 95 0 8 0 nchpl 144 14558 0 14095 61 40 21 61 0 8 0 uvmvnodes 72 6239 0 0 114 0 114 114 0 8 0 vnodes 208 6239 0 0 329 0 329 329 0 8 0 namei 1024 51464 0 51464 3 2 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 vcpupl 1984 39 0 0 5 0 5 5 0 8 0 vmpool 552 53 0 14 3 0 3 3 0 8 0 scsiplug 64 5 0 5 4 4 0 1 0 8 0 scxspl 192 43292 0 43292 41 40 1 6 0 8 1 plimitpl 152 336 0 329 1 0 1 1 0 8 0 sigapl 432 4060 0 4047 3 1 2 3 0 8 0 futexpl 56 97289 0 97288 2 1 1 1 0 8 0 knotepl 112 1049 0 1030 5 4 1 3 0 8 0 kqueuepl 104 1266 0 1264 7 6 1 4 0 8 0 pipepl 112 3140 0 3121 8 6 2 2 0 8 1 fdescpl 488 4061 0 4047 3 0 3 3 0 8 0 filepl 152 38803 0 38706 54 42 12 13 0 8 8 lockfpl 104 1313 0 1313 2 1 1 1 0 8 1 lockfspl 48 458 0 458 2 1 1 1 0 8 1 sessionpl 112 44 0 35 1 0 1 1 0 8 0 pgrppl 48 75 0 66 1 0 1 1 0 8 0 ucredpl 96 4359 0 4351 1 0 1 1 0 8 0 zombiepl 144 4047 0 4047 2 1 1 1 0 8 1 processpl 896 4078 0 4047 4 0 4 4 0 8 0 procpl 632 12715 0 12673 6 1 5 5 0 8 0 srpgc 64 41 0 41 17 17 0 1 0 8 0 sosppl 128 50 0 50 13 13 0 1 0 8 0 sockpl 384 9543 0 9527 94 83 11 23 0 8 8 mcl64k 65536 282 0 0 34 0 34 34 0 8 1 mcl16k 16384 25 0 0 4 2 2 3 0 8 0 mcl12k 12288 17 0 0 2 0 2 2 0 8 0 mcl9k 9216 17 0 0 2 0 2 2 0 8 0 mcl8k 8192 25 0 0 4 1 3 3 0 8 0 mcl4k 4096 25 0 0 4 1 3 3 0 8 0 mcl2k2 2112 8 0 0 1 0 1 1 0 8 0 mcl2k 2048 207 0 0 22 4 18 22 0 8 0 mtagpl 80 56 0 0 1 0 1 1 0 8 0 mbufpl 256 801 0 0 24 0 24 24 0 8 0 bufpl 256 19241 0 12193 441 0 441 441 0 8 0 anonpl 16 546079 0 527247 203 115 88 95 0 124 6 amapchunkpl 152 30406 0 30240 54 43 11 14 0 158 0 amappl16 192 24375 0 23276 197 133 64 67 0 8 8 amappl15 184 1080 0 1080 3 3 0 1 0 8 0 amappl14 176 302 0 297 1 0 1 1 0 8 0 amappl13 168 371 0 371 4 4 0 1 0 8 0 amappl12 160 248 0 245 1 0 1 1 0 8 0 amappl11 152 946 0 936 1 0 1 1 0 8 0 amappl10 144 443 0 435 1 0 1 1 0 8 0 amappl9 136 1640 0 1633 1 0 1 1 0 8 0 amappl8 128 1219 0 1178 2 0 2 2 0 8 0 amappl7 120 572 0 563 1 0 1 1 0 8 0 amappl6 112 932 0 917 1 0 1 1 0 8 0 amappl5 104 572 0 561 1 0 1 1 0 8 0 amappl4 96 4227 0 4192 2 1 1 2 0 8 0 amappl3 88 641 0 629 1 0 1 1 0 8 0 amappl2 80 31338 0 31266 3 1 2 3 0 8 0 amappl1 72 100587 0 100173 26 17 9 20 0 8 0 amappl 80 13477 0 13410 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 64 137 0 8 3 0 3 3 0 8 0 uaddrrnd 24 4114 0 4047 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 4114 0 4047 1 0 1 1 0 8 0 vmmpekpl 168 38884 0 38844 3 0 3 3 0 8 0 vmmpepl 168 527899 0 525598 316 174 142 143 0 357 33 vmsppl 368 4060 0 4047 2 0 2 2 0 8 0 pdppl 4096 8235 0 8161 10 0 10 10 0 8 0 pvpl 32 1369444 0 1348003 387 181 206 221 0 265 25 pmappl 232 4113 0 4061 4 0 4 4 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 707 0 53 20 0 20 20 0 8 1