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 795 30893 74 0x100012 0x480 1 pflogd *173665 65355 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(ffffffff822069c1,ffffffff82206561,2cc,ffffffff8218dd42) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd80642401c8) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff8261c100) at arptimer+0x95 sys/netinet/if_ether.c:120 timeout_run(ffffffff8261c100) at timeout_run+0xc4 timeout_sync_leave sys/kern/kern_timeout.c:177 [inline] timeout_run(ffffffff8261c100) at timeout_run+0xc4 sys/kern/kern_timeout.c:474 softclock_thread(ffff800020a104f0) 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(ffffffff822069c1,ffffffff82206561,2cc,ffffffff8218dd42) at __assert+0x2b sys/kern/subr_prf.c:154 arptfree(fffffd80642401c8) at arptfree+0xfb sys/netinet/if_ether.c:716 arptimer(ffffffff8261c100) at arptimer+0x95 sys/netinet/if_ether.c:120 timeout_run(ffffffff8261c100) at timeout_run+0xc4 timeout_sync_leave sys/kern/kern_timeout.c:177 [inline] timeout_run(ffffffff8261c100) at timeout_run+0xc4 sys/kern/kern_timeout.c:474 softclock_thread(ffff800020a104f0) 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 0xffff800020a24d50 rbx 0xffff800020a24e00 rdx 0xffff800020a104f0 rcx 0 rax 0 r8 0xffffffff81f734ef kprintf+0x16f r9 0x1 r10 0x25 r11 0x3a35ed1a47ba0fe7 r12 0x3000000008 r13 0xffff800020a24d60 r14 0x100 r15 0x1 rip 0xffffffff81194cb8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020a24d40 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (softclock) pid=173665 stat=onproc flags process=14000 proc=40000200 pri=0, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff800020a10c58,0xffff800020a10288 process=0xffff800020a12a80 user=0xffff800020a20000, vmspace=0xffffffff826768f8 estcpu=0, cpticks=2, pctcpu=0.0 user=0, sys=2, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 30383 263327 67248 0 2 0 syz-executor.0 30383 36738 67248 0 3 0x4000080 fsleep syz-executor.0 67248 163724 16330 0 2 0x482 syz-executor.0 36285 254932 16330 0 2 0x2 syz-executor.1 77966 357953 0 0 3 0x14200 acct acct 76203 38764 0 0 3 0x14200 bored sosplice 16330 412657 67766 0 3 0x82 kqread syz-fuzzer 16330 193624 67766 0 2 0x4000482 syz-fuzzer 16330 241484 67766 0 3 0x4000082 thrsleep syz-fuzzer 16330 336967 67766 0 2 0x4000482 syz-fuzzer 16330 369301 67766 0 3 0x4000082 thrsleep syz-fuzzer 16330 220360 67766 0 3 0x4000082 thrsleep syz-fuzzer 16330 27417 67766 0 2 0x4000482 syz-fuzzer 16330 255798 67766 0 3 0x4000082 thrsleep syz-fuzzer 16330 360261 67766 0 3 0x4000082 thrsleep syz-fuzzer 16330 163256 67766 0 3 0x4000082 thrsleep syz-fuzzer 16330 317410 67766 0 3 0x4000082 thrsleep syz-fuzzer 67766 182351 55787 0 3 0x10008a pause ksh 55787 72345 82790 0 3 0x92 select sshd 20636 487159 1 0 3 0x100083 ttyin getty 82790 238029 1 0 3 0x80 select sshd 30893 795 62926 74 7 0x100492 pflogd 62926 416231 1 0 3 0x80 netio pflogd 91605 433386 50549 73 3 0x100090 kqread syslogd 50549 427862 1 0 3 0x100082 netio syslogd 19503 66117 1 77 3 0x100090 poll dhclient 7333 353049 1 0 3 0x80 poll dhclient 97070 236217 0 0 3 0x14200 pgzero zerothread 72475 60096 0 0 3 0x14200 aiodoned aiodoned 69188 494889 0 0 2 0x14200 update 99826 500888 0 0 3 0x14200 cleaner cleaner 64934 228637 0 0 3 0x14200 reaper reaper 39352 101332 0 0 3 0x14200 pgdaemon pagedaemon 95999 240211 0 0 3 0x14200 bored crynlk 98583 91689 0 0 3 0x14200 bored crypto 19017 500226 0 0 3 0x40014200 acpi0 acpi0 60688 64438 0 0 3 0x40014200 idle1 73723 455330 0 0 2 0x14200 softnet 76157 154845 0 0 2 0x14200 systqmp 65002 19525 0 0 3 0x14200 bored systq *65355 173665 0 0 7 0x40014200 softclock 27853 249957 0 0 3 0x40014200 idle0 28728 112995 0 0 3 0x14200 bored smr 1 408524 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 36285 (syz-executor.1) thread 0xffff800023b978d8 (254932) exclusive rrwlock inode r = 0 (0xfffffd8075c800a8) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 rw_enter+0x447 sys/kern/kern_rwlock.c:306 #2 rrw_enter+0x4f sys/kern/kern_rwlock.c:435 #3 VOP_LOCK+0xf0 sys/kern/vfs_vops.c:615 #4 vn_lock+0x81 sys/kern/vfs_vnops.c:574 #5 vget+0x1c3 sys/kern/vfs_subr.c:672 #6 ufs_ihashget+0x141 sys/ufs/ufs/ufs_ihash.c:119 #7 ffs_vget+0x74 sys/ufs/ffs/ffs_vfsops.c:1323 #8 ufs_lookup+0x14b4 sys/ufs/ufs/ufs_lookup.c:487 #9 VOP_LOOKUP+0x5b sys/kern/vfs_vops.c:91 #10 vfs_lookup+0x7a6 sys/kern/vfs_lookup.c:568 #11 namei+0x63c sys/kern/vfs_lookup.c:249 #12 dounlinkat+0x99 sys/kern/vfs_syscalls.c:1785 #13 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #13 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #14 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd8079771f80) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 rw_enter+0x447 sys/kern/kern_rwlock.c:306 #2 rrw_enter+0x4f sys/kern/kern_rwlock.c:435 #3 VOP_LOCK+0xf0 sys/kern/vfs_vops.c:615 #4 vn_lock+0x81 sys/kern/vfs_vnops.c:574 #5 vfs_lookup+0xe6 sys/kern/vfs_lookup.c:419 #6 namei+0x63c sys/kern/vfs_lookup.c:249 #7 dounlinkat+0x99 sys/kern/vfs_syscalls.c:1785 #8 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] #8 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 #9 Xsyscall+0x128 Process 65355 (softclock) thread 0xffff800020a104f0 (173665) exclusive rwlock netlock r = 0 (0xffffffff824f3758) #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 (0xffffffff8246b058) #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 (0xffffffff8262a6d0) #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 9624 7172K 8260K 78643K 26488 0 0 pcb 13 10K 12K 78643K 566 0 0 rtable 136 15K 15K 78643K 1896 0 0 ifaddr 97 19K 21K 78643K 551 0 0 counters 39 33K 33K 78643K 39 0 0 ioctlops 0 0K 4K 78643K 1638 0 0 iov 0 0K 24K 78643K 875 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1233 77K 78K 78643K 6061 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 32 0 0 VM map 39 19K 20K 78643K 45 0 0 sem 12 0K 0K 78643K 3973 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1809 196K 290K 78643K 12766 0 0 file desc 5 13K 25K 78643K 3688 0 0 sigio 0 0K 0K 78643K 30 0 0 proc 62 63K 95K 78643K 1623 0 0 subproc 32 2K 2K 78643K 412 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 1670 0 0 in_multi 30 1K 2K 78643K 373 0 0 ether_multi 1 0K 0K 78643K 30 0 0 mrt 1 0K 0K 78643K 25 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 96 424K 424K 78643K 96 0 0 exec 0 0K 1K 78643K 762 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 174 300K 309K 78643K 13832 0 0 UVM aobj 130 5K 5K 78643K 131 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 661 0 0 NDP 22 0K 1K 78643K 178 0 0 temp 242 3565K 4205K 78643K 82688 0 0 kqueue 0 0K 0K 78643K 18 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 60 0 53 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 267 0 265 1 0 1 1 0 8 0 rtentry 112 349 0 299 2 0 2 2 0 8 0 unpcb 120 3992 0 3980 3 2 1 2 0 8 0 syncache 264 18 0 18 10 10 0 1 0 8 0 sackhl 24 1 0 1 1 1 0 1 0 8 0 tcpqe 32 17 0 17 2 2 0 1 0 8 0 tcpcb 544 1730 0 1725 30 29 1 13 0 8 0 inpcb 280 6152 0 6144 31 29 2 9 0 8 1 rttmr 72 8 0 8 7 6 1 1 0 8 1 ip6q 72 2 0 2 1 1 0 1 0 8 0 ip6af 40 4 0 4 1 1 0 1 0 8 0 nd6 48 55 0 53 3 2 1 1 0 8 0 pkpcb 40 16 0 16 4 4 0 1 0 8 0 swfcl 56 6 0 0 1 0 1 1 0 8 0 ppxss 1128 59 0 59 19 18 1 1 0 8 1 pffrag 232 315 0 315 19 19 0 9 0 482 0 pffrnode 88 68 0 68 7 7 0 1 0 8 0 pffrent 40 1701 0 1701 9 9 0 2 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 24 444 0 437 2 0 2 2 0 8 0 pfstkey 112 446 0 439 8 6 2 7 0 8 0 pfstate 328 446 0 439 25 23 2 20 0 8 0 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 4 0 0 4 0 4 4 0 8 0 art_heap4 256 1513 0 1299 27 12 15 16 0 8 0 art_table 32 1517 0 1299 3 0 3 3 0 8 0 art_node 16 348 0 305 1 0 1 1 0 8 0 sysvmsgpl 40 34 0 19 1 0 1 1 0 8 0 semupl 112 2 0 2 1 1 0 1 0 8 0 semapl 112 3971 0 3961 1 0 1 1 0 8 0 shmpl 112 129 0 1 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 6499 0 5080 46 0 46 46 0 8 0 ffsino 272 6499 0 5080 95 0 95 95 0 8 0 nchpl 144 11753 0 11285 61 40 21 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 39626 0 39626 3 2 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 vcpupl 1984 37 0 0 5 0 5 5 0 8 0 vmpool 552 43 0 6 3 0 3 3 0 8 0 scsiplug 64 5 0 5 3 3 0 1 0 8 0 scxspl 192 36519 0 36519 32 31 1 7 0 8 1 plimitpl 152 212 0 204 1 0 1 1 0 8 0 sigapl 432 3820 0 3805 5 3 2 3 0 8 0 futexpl 56 96043 0 96042 2 1 1 1 0 8 0 knotepl 112 601 0 582 1 0 1 1 0 8 0 kqueuepl 104 1014 0 1012 7 6 1 4 0 8 0 pipepl 112 3990 0 3971 7 6 1 2 0 8 0 fdescpl 488 3821 0 3805 3 0 3 3 0 8 0 filepl 152 32985 0 32883 39 34 5 14 0 8 0 lockfpl 104 1384 0 1383 1 0 1 1 0 8 0 lockfspl 48 447 0 446 1 0 1 1 0 8 0 sessionpl 112 40 0 29 1 0 1 1 0 8 0 pgrppl 48 68 0 57 1 0 1 1 0 8 0 ucredpl 96 2757 0 2748 1 0 1 1 0 8 0 zombiepl 144 3806 0 3806 1 0 1 1 0 8 1 processpl 896 3839 0 3806 6 2 4 5 0 8 0 procpl 632 11871 0 11827 6 1 5 5 0 8 0 srpgc 64 40 0 40 15 15 0 1 0 8 0 sosppl 128 52 0 52 8 8 0 1 0 8 0 sockpl 384 10453 0 10431 49 45 4 14 0 8 0 mcl64k 65536 181 0 0 19 1 18 19 0 8 1 mcl16k 16384 16 0 0 2 0 2 2 0 8 0 mcl12k 12288 25 0 0 2 0 2 2 0 8 0 mcl9k 9216 17 0 0 2 0 2 2 0 8 0 mcl8k 8192 27 0 0 3 0 3 3 0 8 0 mcl4k 4096 46 0 0 5 1 4 5 0 8 0 mcl2k2 2112 11 0 0 1 0 1 1 0 8 0 mcl2k 2048 175 0 0 20 1 19 20 0 8 0 mtagpl 80 367 0 0 4 0 4 4 0 8 0 mbufpl 256 1227 0 0 61 0 61 61 0 8 0 bufpl 256 14889 0 7831 442 0 442 442 0 8 0 anonpl 16 434732 0 413244 172 73 99 103 0 124 12 amapchunkpl 152 26891 0 26718 41 32 9 20 0 158 0 amappl16 192 18621 0 17424 148 84 64 71 0 8 4 amappl15 184 1393 0 1393 3 3 0 1 0 8 0 amappl14 176 971 0 966 1 0 1 1 0 8 0 amappl13 168 265 0 264 1 0 1 1 0 8 0 amappl12 160 304 0 303 4 3 1 1 0 8 0 amappl11 152 566 0 549 1 0 1 1 0 8 0 amappl10 144 373 0 369 1 0 1 1 0 8 0 amappl9 136 1124 0 1121 1 0 1 1 0 8 0 amappl8 128 706 0 665 2 0 2 2 0 8 0 amappl7 120 479 0 470 1 0 1 1 0 8 0 amappl6 112 503 0 490 1 0 1 1 0 8 0 amappl5 104 626 0 612 1 0 1 1 0 8 0 amappl4 96 3873 0 3838 2 1 1 2 0 8 0 amappl3 88 1442 0 1436 1 0 1 1 0 8 0 amappl2 80 29431 0 29357 3 1 2 3 0 8 0 amappl1 72 96456 0 96020 26 16 10 20 0 8 0 amappl 80 12570 0 12504 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 18 0 17 1 0 1 1 0 8 0 aobjpl 64 130 0 1 3 0 3 3 0 8 0 uaddrrnd 24 3864 0 3805 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 3864 0 3805 1 0 1 1 0 8 0 vmmpekpl 168 36256 0 36217 4 1 3 3 0 8 0 vmmpepl 168 491612 0 489158 336 220 116 157 0 357 1 vmsppl 368 3820 0 3805 2 0 2 2 0 8 0 pdppl 4096 7735 0 7659 15 5 10 11 0 8 0 pvpl 32 1157895 0 1133926 386 155 231 235 0 265 36 pmappl 232 3863 0 3811 4 0 4 4 0 8 0 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 735 0 54 20 0 20 20 0 8 0