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 512175 63866 74 0x100012 0 1 pflogd *473410 35461 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(ffffffff82207402,ffffffff82205b14,2cc,ffffffff8218bbca) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd8062b450e8) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff82600aa8) at arptimer+0x95 sys/netinet/if_ether.c:120 timeout_run(ffffffff82600aa8) at timeout_run+0xc4 timeout_sync_leave sys/kern/kern_timeout.c:177 [inline] timeout_run(ffffffff82600aa8) at timeout_run+0xc4 sys/kern/kern_timeout.c:474 softclock_thread(ffff800020a113c0) 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(ffffffff82207402,ffffffff82205b14,2cc,ffffffff8218bbca) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd8062b450e8) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff82600aa8) at arptimer+0x95 sys/netinet/if_ether.c:120 timeout_run(ffffffff82600aa8) at timeout_run+0xc4 timeout_sync_leave sys/kern/kern_timeout.c:177 [inline] timeout_run(ffffffff82600aa8) at timeout_run+0xc4 sys/kern/kern_timeout.c:474 softclock_thread(ffff800020a113c0) 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 0xffff800020a25b40 rbx 0xffff800020a25bf0 rdx 0xffff800020a113c0 rcx 0 rax 0 r8 0xffffffff8142715f kprintf+0x16f r9 0x1 r10 0x25 r11 0x53c5f4080069598 r12 0x3000000008 r13 0xffff800020a25b50 r14 0x100 r15 0x1 rip 0xffffffff81126748 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020a25b30 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (softclock) pid=473410 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff800020a11638,0xffff800020a11158 process=0xffff800020a12e00 user=0xffff800020a20000, vmspace=0xffffffff82622568 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 21451 197239 38421 0 2 0x482 syz-executor.0 44884 404887 38421 0 3 0x82 piperd syz-executor.1 25805 257408 0 0 3 0x14200 acct acct 65089 406702 1 0 3 0x100083 ttyin getty 70917 223850 0 0 3 0x14200 bored sosplice 38421 273033 71754 0 3 0x82 thrsleep syz-fuzzer 38421 470991 71754 0 3 0x4000082 thrsleep syz-fuzzer 38421 407350 71754 0 3 0x4000082 thrsleep syz-fuzzer 38421 354044 71754 0 3 0x4000082 kqread syz-fuzzer 38421 449244 71754 0 3 0x4000082 thrsleep syz-fuzzer 38421 257512 71754 0 3 0x4000082 thrsleep syz-fuzzer 38421 499827 71754 0 3 0x4000082 thrsleep syz-fuzzer 38421 370934 71754 0 3 0x4000082 thrsleep syz-fuzzer 38421 516494 71754 0 3 0x4000082 thrsleep syz-fuzzer 38421 345547 71754 0 3 0x4000082 thrsleep syz-fuzzer 71754 121414 45419 0 3 0x10008a pause ksh 45419 65368 95540 0 3 0x92 select sshd 95540 48415 1 0 3 0x80 select sshd 63866 512175 77762 74 7 0x100012 pflogd 77762 22119 1 0 3 0x80 netio pflogd 62830 411253 55680 73 3 0x100090 kqread syslogd 55680 310122 1 0 3 0x100082 netio syslogd 46443 476856 1 77 3 0x100090 poll dhclient 40070 222396 1 0 3 0x80 poll dhclient 25404 438659 0 0 2 0x14200 zerothread 85454 364106 0 0 3 0x14200 aiodoned aiodoned 83336 316713 0 0 3 0x14200 syncer update 92182 253219 0 0 3 0x14200 cleaner cleaner 19810 217278 0 0 3 0x14200 reaper reaper 6966 149938 0 0 3 0x14200 pgdaemon pagedaemon 64656 209205 0 0 3 0x14200 bored crynlk 53285 13084 0 0 3 0x14200 bored crypto 47934 100994 0 0 3 0x40014200 acpi0 acpi0 24894 499573 0 0 3 0x40014200 idle1 17690 412105 0 0 3 0x14200 bored softnet 13546 468652 0 0 3 0x14200 bored systqmp 17193 43367 0 0 3 0x14200 bored systq *35461 473410 0 0 7 0x40014200 softclock 12071 94521 0 0 3 0x40014200 idle0 26472 289422 0 0 3 0x14200 bored smr 1 418758 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 35461 (softclock) thread 0xffff800020a113c0 (473410) exclusive rwlock netlock r = 0 (0xffffffff824d7598) #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 (0xffffffff82506c88) #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 (0xffffffff826603d0) #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 9638 7120K 9825K 78643K 52096 0 0 pcb 13 12K 14K 78643K 1595 0 0 rtable 121 6K 7K 78643K 4395 0 0 ifaddr 135 34K 36K 78643K 1464 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 4K 78643K 2070 0 0 iov 0 0K 32K 78643K 1517 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1235 78K 78K 78643K 12962 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 100 0 0 VM map 56 28K 28K 78643K 86 0 0 sem 12 1K 1K 78643K 255 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12765 0 0 file desc 4 9K 25K 78643K 7587 0 0 sigio 0 0K 0K 78643K 50 0 0 proc 62 63K 95K 78643K 3137 0 0 subproc 32 2K 2K 78643K 782 0 0 NFS srvsock 1 0K 0K 78643K 1 0 0 NFS daemon 1 16K 16K 78643K 1 0 0 ip_moptions 0 0K 0K 78643K 638 0 0 in_multi 43 2K 3K 78643K 896 0 0 ether_multi 1 0K 0K 78643K 85 0 0 mrt 0 0K 0K 78643K 41 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 114 503K 503K 78643K 114 0 0 exec 0 0K 1K 78643K 1555 0 0 pfkey data 0 0K 0K 78643K 2 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 208 463K 465K 78643K 27905 0 0 UVM aobj 130 5K 6K 78643K 140 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 1660 0 0 NDP 25 0K 1K 78643K 444 0 0 temp 264 3561K 4201K 78643K 261333 0 0 kqueue 0 0K 0K 78643K 84 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 64 108 0 99 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 5793 0 5791 1 0 1 1 0 8 0 rtentry 112 700 0 656 2 0 2 2 0 8 0 unpcb 120 4430 0 4418 7 6 1 2 0 8 0 syncache 264 44 0 44 19 18 1 1 0 8 1 tcpqe 32 81 0 81 10 10 0 1 0 8 0 tcpcb 544 3120 0 3116 29 28 1 13 0 8 0 inpcb 280 14795 0 14788 45 40 5 13 0 8 4 rttmr 72 12 0 11 4 3 1 1 0 8 0 ip6q 72 6 0 6 4 4 0 1 0 8 0 ip6af 40 15 0 15 3 3 0 1 0 8 0 nd6 48 117 0 115 4 3 1 1 0 8 0 pkpcb 40 50 0 50 16 16 0 1 0 8 0 swfcl 56 4 0 0 1 0 1 1 0 8 0 ppxss 1128 189 0 189 20 19 1 1 0 8 1 pffrag 232 163 0 163 24 23 1 1 0 482 1 pffrnode 88 163 0 163 24 23 1 1 0 8 1 pffrent 40 4451 0 4451 24 23 1 1 0 8 1 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 24 609 0 547 1 0 1 1 0 8 0 pfstkey 112 610 0 548 3 0 3 3 0 8 0 pfstate 328 610 0 548 8 2 6 8 0 8 0 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 12 0 10 8 6 2 3 0 8 0 art_heap4 256 3208 0 2958 49 30 19 19 0 8 0 art_table 32 3220 0 2968 3 0 3 3 0 8 0 art_node 16 694 0 653 1 0 1 1 0 8 0 sysvmsgpl 40 55 0 47 1 0 1 1 0 8 0 semupl 112 3 0 3 1 1 0 1 0 8 0 semapl 112 251 0 241 1 0 1 1 0 8 0 shmpl 112 138 0 10 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 12596 0 11162 48 1 47 47 0 8 0 ffsino 272 12596 0 11162 96 0 96 96 0 8 0 nchpl 144 23783 0 23264 61 40 21 61 0 8 0 uvmvnodes 72 6344 0 0 116 0 116 116 0 8 0 vnodes 208 6344 0 0 334 0 334 334 0 8 0 namei 1024 92832 0 92832 2 1 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 vcpupl 1984 54 0 0 7 0 7 7 0 8 0 vmpool 552 84 0 30 8 4 4 4 0 8 0 scsiplug 64 9 0 9 7 7 0 1 0 8 0 scxspl 192 82841 0 82841 43 42 1 6 0 8 1 plimitpl 152 600 0 592 1 0 1 1 0 8 0 sigapl 432 7658 0 7644 5 3 2 3 0 8 0 futexpl 56 184407 0 184407 2 1 1 1 0 8 1 knotepl 112 1870 0 1851 2 1 1 2 0 8 0 kqueuepl 104 2118 0 2116 7 6 1 4 0 8 0 pipepl 112 4364 0 4345 15 14 1 2 0 8 0 fdescpl 488 7659 0 7644 3 0 3 3 0 8 0 filepl 152 73790 0 73690 63 55 8 14 0 8 4 lockfpl 104 2466 0 2465 1 0 1 1 0 8 0 lockfspl 48 838 0 837 1 0 1 1 0 8 0 sessionpl 112 65 0 54 1 0 1 1 0 8 0 pgrppl 48 851 0 840 1 0 1 1 0 8 0 ucredpl 96 8338 0 8329 1 0 1 1 0 8 0 zombiepl 144 7648 0 7647 2 1 1 1 0 8 0 processpl 896 7680 0 7647 6 2 4 5 0 8 0 procpl 632 24731 0 24689 6 1 5 5 0 8 0 srpgc 64 67 0 67 21 21 0 1 0 8 0 sosppl 128 162 0 162 20 19 1 1 0 8 1 sockpl 384 25329 0 25308 82 75 7 22 0 8 4 mcl64k 65536 268 0 0 33 29 4 33 0 8 0 mcl16k 16384 24 0 0 3 1 2 3 0 8 0 mcl12k 12288 17 0 0 2 0 2 2 0 8 0 mcl9k 9216 23 0 0 2 0 2 2 0 8 0 mcl8k 8192 17 0 0 3 0 3 3 0 8 0 mcl4k 4096 26 0 0 4 1 3 3 0 8 0 mcl2k2 2112 8 0 0 1 0 1 1 0 8 0 mcl2k 2048 201 0 0 20 4 16 20 0 8 0 mtagpl 80 641 0 0 8 0 8 8 0 8 0 mbufpl 256 1160 0 0 52 0 52 52 0 8 0 bufpl 256 26142 0 19094 441 0 441 441 0 8 0 anonpl 16 971473 0 953070 221 130 91 93 0 124 8 amapchunkpl 152 54828 0 54681 71 63 8 14 0 158 0 amappl16 192 44892 0 43828 294 228 66 66 0 8 12 amappl15 184 1150 0 1150 4 4 0 1 0 8 0 amappl14 176 2011 0 2009 1 0 1 1 0 8 0 amappl13 168 588 0 587 1 0 1 1 0 8 0 amappl12 160 703 0 697 1 0 1 1 0 8 0 amappl11 152 565 0 550 1 0 1 1 0 8 0 amappl10 144 1499 0 1495 1 0 1 1 0 8 0 amappl9 136 1729 0 1723 1 0 1 1 0 8 0 amappl8 128 1386 0 1330 2 0 2 2 0 8 0 amappl7 120 1712 0 1704 1 0 1 1 0 8 0 amappl6 112 516 0 502 1 0 1 1 0 8 0 amappl5 104 1197 0 1180 1 0 1 1 0 8 0 amappl4 96 7295 0 7262 2 1 1 2 0 8 0 amappl3 88 2856 0 2842 1 0 1 1 0 8 0 amappl2 80 58821 0 58757 3 1 2 3 0 8 0 amappl1 72 182474 0 182049 25 15 10 20 0 8 0 amappl 80 25855 0 25783 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 64 139 0 10 3 0 3 3 0 8 0 uaddrrnd 24 7743 0 7644 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 7743 0 7644 1 0 1 1 0 8 0 vmmpekpl 168 65512 0 65468 3 0 3 3 0 8 0 vmmpepl 168 996803 0 994547 380 240 140 145 0 357 30 vmsppl 368 7658 0 7644 2 0 2 2 0 8 0 pdppl 4096 15493 0 15402 17 4 13 13 0 8 1 pvpl 32 2524735 0 2503472 441 227 214 216 0 265 29 pmappl 232 7742 0 7674 7 2 5 5 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 766 0 107 20 0 20 20 0 8 0