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 189108 50584 0 0x2 0 1 syz-executor.1 *168463 88900 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(ffffffff82206ea2,ffffffff82204a3b,2cc,ffffffff8218c169) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd80653be858) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff825538c0) at arptimer+0x95 sys/netinet/if_ether.c:120 timeout_run(ffffffff825538c0) at timeout_run+0xc4 timeout_sync_leave sys/kern/kern_timeout.c:177 [inline] timeout_run(ffffffff825538c0) at timeout_run+0xc4 sys/kern/kern_timeout.c:474 softclock_thread(ffff800020a10ed0) 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(ffffffff82206ea2,ffffffff82204a3b,2cc,ffffffff8218c169) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd80653be858) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff825538c0) at arptimer+0x95 sys/netinet/if_ether.c:120 timeout_run(ffffffff825538c0) at timeout_run+0xc4 timeout_sync_leave sys/kern/kern_timeout.c:177 [inline] timeout_run(ffffffff825538c0) at timeout_run+0xc4 sys/kern/kern_timeout.c:474 softclock_thread(ffff800020a10ed0) 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 0xffff800020a24ed0 rbx 0xffff800020a24f80 rdx 0xffff800020a10ed0 rcx 0 rax 0 r8 0xffffffff81ee69df kprintf+0x16f r9 0x1 r10 0x25 r11 0xb5b251c0601062be r12 0x3000000008 r13 0xffff800020a24ee0 r14 0x100 r15 0x1 rip 0xffffffff81d72d68 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020a24ec0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (softclock) pid=168463 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff800020a11148,0xffff800020a10c68 process=0xffff800020a12380 user=0xffff800020a20000, vmspace=0xffffffff8264c400 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 13347 436410 54169 0 2 0 syz-executor.0 13347 519427 54169 0 2 0x4000000 syz-executor.0 13347 367907 54169 0 2 0x4000000 syz-executor.0 30509 308080 50584 0 2 0 syz-executor.1 30509 464111 50584 0 2 0x4000000 syz-executor.1 30509 264296 50584 0 2 0x4000000 syz-executor.1 54169 409912 70551 0 2 0x482 syz-executor.0 50584 189108 70551 0 7 0x2 syz-executor.1 75596 489042 1 0 3 0x100083 ttyin getty 69094 368640 0 0 3 0x14200 bored sosplice 70551 380976 91513 0 3 0x82 thrsleep syz-fuzzer 70551 456892 91513 0 3 0x4000082 thrsleep syz-fuzzer 70551 221774 91513 0 3 0x4000082 thrsleep syz-fuzzer 70551 140912 91513 0 3 0x4000082 thrsleep syz-fuzzer 70551 177827 91513 0 3 0x4000082 thrsleep syz-fuzzer 70551 4611 91513 0 3 0x4000082 kqread syz-fuzzer 70551 396018 91513 0 3 0x4000082 thrsleep syz-fuzzer 70551 262974 91513 0 3 0x4000082 thrsleep syz-fuzzer 70551 449204 91513 0 3 0x4000082 thrsleep syz-fuzzer 70551 294577 91513 0 3 0x4000082 thrsleep syz-fuzzer 91513 395273 29496 0 3 0x10008a pause ksh 29496 510133 70584 0 3 0x92 select sshd 70584 168377 1 0 3 0x80 select sshd 88544 254141 63738 74 2 0x100092 pflogd 63738 489114 1 0 3 0x80 netio pflogd 61972 383807 62680 73 3 0x100090 kqread syslogd 62680 176726 1 0 3 0x100082 netio syslogd 41770 464075 1 77 3 0x100090 poll dhclient 73006 184750 1 0 3 0x80 poll dhclient 70792 37306 0 0 2 0x14200 zerothread 78437 302634 0 0 3 0x14200 aiodoned aiodoned 35180 174332 0 0 3 0x14200 syncer update 81021 7690 0 0 3 0x14200 cleaner cleaner 31106 149526 0 0 3 0x14200 reaper reaper 62944 67928 0 0 3 0x14200 pgdaemon pagedaemon 66565 301580 0 0 3 0x14200 bored crynlk 37051 46508 0 0 3 0x14200 bored crypto 13006 385017 0 0 3 0x40014200 acpi0 acpi0 48321 219329 0 0 3 0x40014200 idle1 5683 405897 0 0 3 0x14200 bored softnet 46774 505944 0 0 3 0x14200 bored systqmp 77862 26529 0 0 3 0x14200 bored systq *88900 168463 0 0 7 0x40014200 softclock 87362 100722 0 0 3 0x40014200 idle0 72701 451371 0 0 3 0x14200 bored smr 1 301134 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 88900 (softclock) thread 0xffff800020a10ed0 (168463) exclusive rwlock netlock r = 0 (0xffffffff82464b38) #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 (0xffffffff8248c8f0) #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 (0xffffffff8266bc00) #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 9661 6793K 15050K 78643K 60876 0 0 pcb 13 12K 14K 78643K 1738 0 0 rtable 106 13K 15K 78643K 6209 0 0 ifaddr 109 27K 30K 78643K 1737 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 4K 78643K 2079 0 0 iov 0 0K 32K 78643K 6308 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1221 77K 78K 78643K 15670 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 126 0 0 VM map 107 53K 53K 78643K 130 0 0 sem 12 0K 1K 78643K 3698 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1808 196K 290K 78643K 12765 0 0 file desc 6 17K 25K 78643K 9182 0 0 sigio 0 0K 0K 78643K 182 0 0 proc 62 63K 95K 78643K 4098 0 0 subproc 32 2K 2K 78643K 1173 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 896 0 0 in_multi 20 1K 2K 78643K 1212 0 0 ether_multi 1 0K 0K 78643K 90 0 0 mrt 0 0K 0K 78643K 47 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 1960 0 0 pfkey data 0 0K 0K 78643K 4 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 298 890K 895K 78643K 33886 0 0 UVM aobj 130 8K 9K 78643K 185 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 1842 0 0 NDP 26 0K 1K 78643K 560 0 0 temp 270 3566K 4206K 78643K 313296 0 0 kqueue 0 0K 0K 78643K 46 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 64 200 0 195 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 864 0 862 1 0 1 1 0 8 0 rtentry 112 1121 0 1087 2 0 2 2 0 8 0 unpcb 120 7461 0 7441 12 11 1 2 0 8 0 syncache 264 63 0 63 23 23 0 1 0 8 0 tcpqe 32 51 0 51 15 15 0 1 0 8 0 tcpcb 544 3602 0 3597 32 30 2 13 0 8 1 inpcb 280 14184 0 14176 68 66 2 13 0 8 1 rttmr 72 15 0 15 3 3 0 1 0 8 0 ip6q 72 4 0 4 3 3 0 1 0 8 0 ip6af 40 12 0 12 3 3 0 1 0 8 0 nd6 48 174 0 174 4 3 1 1 0 8 1 pkpcb 40 38 0 38 14 14 0 1 0 8 0 swfcl 56 9 0 0 1 0 1 1 0 8 0 ppxss 1128 235 0 235 30 29 1 1 0 8 1 pffrag 232 186 0 186 40 39 1 1 0 482 1 pffrnode 88 186 0 186 40 39 1 1 0 8 1 pffrent 40 5153 0 5153 40 39 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 24 708 0 672 1 0 1 1 0 8 0 pfstkey 112 710 0 674 3 0 3 3 0 8 0 pfstate 328 710 0 674 9 3 6 7 0 8 0 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 44 0 42 26 24 2 3 0 8 0 art_heap4 256 4780 0 4608 64 47 17 23 0 8 1 art_table 32 4824 0 4650 4 1 3 3 0 8 0 art_node 16 1120 0 1088 1 0 1 1 0 8 0 sysvmsgpl 40 44 0 36 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 3694 0 3684 1 0 1 1 0 8 0 shmpl 112 183 0 55 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 14769 0 13323 47 0 47 47 0 8 0 ffsino 272 14769 0 13323 99 2 97 97 0 8 0 nchpl 144 27725 0 27252 61 41 20 61 0 8 0 uvmvnodes 72 7466 0 0 136 0 136 136 0 8 0 vnodes 208 7466 0 0 393 0 393 393 0 8 0 namei 1024 103231 0 103231 3 2 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 vcpupl 1984 106 0 1 14 0 14 14 0 8 0 vmpool 552 128 0 23 8 0 8 8 0 8 0 scsiplug 64 13 0 13 9 9 0 1 0 8 0 scxspl 192 92834 0 92834 69 68 1 6 0 8 1 plimitpl 152 746 0 738 1 0 1 1 0 8 0 sigapl 432 9183 0 9167 7 5 2 3 0 8 0 futexpl 56 213952 0 213952 2 1 1 1 0 8 1 knotepl 112 2609 0 2590 7 5 2 3 0 8 1 kqueuepl 104 2528 0 2524 7 6 1 4 0 8 0 pipepl 112 17094 0 17075 39 37 2 2 0 8 1 fdescpl 488 9184 0 9167 3 0 3 3 0 8 0 filepl 152 89726 0 89619 76 70 6 14 0 8 1 lockfpl 104 2969 0 2968 1 0 1 1 0 8 0 lockfspl 48 989 0 988 1 0 1 1 0 8 0 sessionpl 112 87 0 76 1 0 1 1 0 8 0 pgrppl 48 288 0 277 1 0 1 1 0 8 0 ucredpl 96 8147 0 8136 1 0 1 1 0 8 0 zombiepl 144 9176 0 9176 2 1 1 1 0 8 1 processpl 896 9209 0 9176 6 2 4 5 0 8 0 procpl 632 29586 0 29540 9 4 5 5 0 8 1 srpgc 64 109 0 109 38 37 1 1 0 8 1 sosppl 128 160 0 160 31 31 0 1 0 8 0 sockpl 384 22755 0 22725 99 93 6 23 0 8 2 mcl64k 65536 588 0 0 70 67 3 34 0 8 0 mcl16k 16384 25 0 0 3 0 3 3 0 8 0 mcl12k 12288 50 0 0 2 0 2 2 0 8 0 mcl9k 9216 17 0 0 2 0 2 2 0 8 0 mcl8k 8192 41 0 0 5 2 3 3 0 8 0 mcl4k 4096 33 0 0 4 1 3 3 0 8 0 mcl2k2 2112 17 0 0 2 0 2 2 0 8 0 mcl2k 2048 189 0 0 20 4 16 20 0 8 0 mtagpl 80 100 0 0 1 0 1 1 0 8 0 mbufpl 256 1005 0 0 31 0 31 31 0 8 0 bufpl 256 36012 0 28545 467 0 467 467 0 8 0 anonpl 16 1143045 0 1119138 372 271 101 116 0 124 0 amapchunkpl 152 70787 0 70604 158 150 8 21 0 158 0 amappl16 192 50291 0 48884 403 332 71 85 0 8 0 amappl15 184 2685 0 2681 7 6 1 1 0 8 0 amappl14 176 1757 0 1752 1 0 1 1 0 8 0 amappl13 168 1060 0 1059 1 0 1 1 0 8 0 amappl12 160 1177 0 1173 1 0 1 1 0 8 0 amappl11 152 2093 0 2078 1 0 1 1 0 8 0 amappl10 144 304 0 299 1 0 1 1 0 8 0 amappl9 136 2259 0 2252 1 0 1 1 0 8 0 amappl8 128 1873 0 1806 5 2 3 3 0 8 0 amappl7 120 587 0 578 1 0 1 1 0 8 0 amappl6 112 1916 0 1901 1 0 1 1 0 8 0 amappl5 104 1821 0 1805 1 0 1 1 0 8 0 amappl4 96 9399 0 9359 7 6 1 2 0 8 0 amappl3 88 2781 0 2757 1 0 1 1 0 8 0 amappl2 80 69972 0 69873 7 4 3 3 0 8 0 amappl1 72 219492 0 219026 25 15 10 20 0 8 0 amappl 80 31156 0 31057 3 0 3 3 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 64 184 0 55 3 0 3 3 0 8 0 uaddrrnd 24 9312 0 9167 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 9312 0 9167 1 0 1 1 0 8 0 vmmpekpl 168 97674 0 97621 3 0 3 3 0 8 0 vmmpepl 168 1187963 0 1184893 557 385 172 175 0 357 33 vmsppl 368 9183 0 9167 2 0 2 2 0 8 0 pdppl 4096 18631 0 18485 23 4 19 19 0 8 0 pvpl 32 2882265 0 2860237 641 445 196 232 0 265 12 pmappl 232 9311 0 9190 9 1 8 8 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 856 0 186 21 0 21 21 0 8 0