panic: Data modified on freelist: word 5 of object 0xffff8000006a0300 size 0xc0 previous type devbuf (0xd != 0xdeadbeef) Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *119579 10937 0 0 0 0 dhclient db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic() at panic+0x15c sys/kern/subr_prf.c:207 malloc(c0,5,9) at malloc+0xa23 sys/kern/kern_malloc.c:331 rtm_report(fffffd8036d681c0,4,c4406da1,0) at rtm_report+0x2d9 sys/net/rtsock.c:654 route_output(fffffd802e0ea400,fffffd8037002180,0,0) at route_output+0x6b7 sys/net/rtsock.c:824 route_usrreq(fffffd8037002180,9,fffffd802e0ea400,0,0,ffff8000ffff8280) at route_usrreq+0x363 sys/net/rtsock.c:275 sosend(fffffd8037002180,0,ffff800014886a90,0,0,0) at sosend+0x63d sys/kern/uipc_socket.c:524 dofilewritev(ffff8000ffff8280,6,ffff800014886a90,0,ffff800014886b80) at dofilewritev+0x1ac sys/kern/sys_generic.c:364 sys_writev(ffff8000ffff8280,ffff800014886b30,ffff800014886b80) at sys_writev+0xa7 sys/kern/sys_generic.c:311 syscall(ffff800014886c00) at syscall+0x507 sys/arch/amd64/amd64/trap.c:555 Xsyscall(0,79,0,79,c4406da1,f8593a1a000) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffe7dd0, count: 4 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> ddb> set $lines = 0 ddb> set $maxwidth = 0 ddb> show panic Data modified on freelist: word 5 of object 0xffff8000006a0300 size 0xc0 previous type devbuf (0xd != 0xdeadbeef) ddb> 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 malloc(c0,5,9) at malloc+0xa23 sys/kern/kern_malloc.c:331 rtm_report(fffffd8036d681c0,4,c4406da1,0) at rtm_report+0x2d9 sys/net/rtsock.c:654 route_output(fffffd802e0ea400,fffffd8037002180,0,0) at route_output+0x6b7 sys/net/rtsock.c:824 route_usrreq(fffffd8037002180,9,fffffd802e0ea400,0,0,ffff8000ffff8280) at route_usrreq+0x363 sys/net/rtsock.c:275 sosend(fffffd8037002180,0,ffff800014886a90,0,0,0) at sosend+0x63d sys/kern/uipc_socket.c:524 dofilewritev(ffff8000ffff8280,6,ffff800014886a90,0,ffff800014886b80) at dofilewritev+0x1ac sys/kern/sys_generic.c:364 sys_writev(ffff8000ffff8280,ffff800014886b30,ffff800014886b80) at sys_writev+0xa7 sys/kern/sys_generic.c:311 syscall(ffff800014886c00) at syscall+0x507 sys/arch/amd64/amd64/trap.c:555 Xsyscall(0,79,0,79,c4406da1,f8593a1a000) at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffe7dd0, count: -11 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff8000148863a0 rbx 0xffff800014886450 rdx 0x2 rcx 0 rax 0 r8 0xffff800014886360 r9 0x1 r10 0 r11 0x3cb0e7313acdeb4c r12 0x3000000008 r13 0xffff8000148863b0 r14 0x100 r15 0x1 rip 0xffffffff82159ec8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800014886390 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (dhclient) pid=119579 stat=onproc flags process=0 proc=0 pri=50, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff8000ffff9150,0xffff8000ffff8780 process=0xffff8000ffff66d0 user=0xffff800014881000, vmspace=0xfffffd803f014330 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 8213 489720 1538 0 2 0 syz-executor.1 8213 56340 1538 0 2 0x4000000 syz-executor.1 1538 318063 93648 0 3 0x82 nanosleep syz-executor.1 29608 223078 1 0 3 0x100083 ttyin getty 93481 212970 0 0 3 0x14200 bored sosplice 93648 389395 86162 0 3 0x82 thrsleep syz-fuzzer 93648 206743 86162 0 3 0x4000082 thrsleep syz-fuzzer 93648 168664 86162 0 3 0x4000082 thrsleep syz-fuzzer 93648 325333 86162 0 3 0x4000082 thrsleep syz-fuzzer 93648 353782 86162 0 3 0x4000082 kqread syz-fuzzer 93648 226728 86162 0 3 0x4000082 thrsleep syz-fuzzer 93648 121638 86162 0 3 0x4000082 thrsleep syz-fuzzer 93648 40975 86162 0 3 0x4000082 thrsleep syz-fuzzer 86162 256091 11706 0 3 0x10008a pause ksh 11706 205548 507 0 3 0x92 select sshd 507 385128 1 0 3 0x80 select sshd 29439 221267 57609 73 3 0x100090 kqread syslogd 57609 489283 1 0 3 0x100082 netio syslogd 11038 363672 1 77 2 0x100010 dhclient *10937 119579 1 0 7 0 dhclient 44406 397731 0 0 2 0x14200 zerothread 28301 39817 0 0 3 0x14200 aiodoned aiodoned 83206 200987 0 0 3 0x14200 syncer update 16882 413110 0 0 3 0x14200 cleaner cleaner 88792 70867 0 0 3 0x14200 reaper reaper 68392 121585 0 0 3 0x14200 pgdaemon pagedaemon 73261 199533 0 0 3 0x14200 bored crynlk 81491 362484 0 0 3 0x14200 bored crypto 40689 90114 0 0 3 0x40014200 acpi0 acpi0 77067 281419 0 0 2 0x14200 softnet 68800 110990 0 0 2 0x14200 systqmp 22335 399082 0 0 3 0x14200 bored systq 76635 241804 0 0 3 0x40014200 bored softclock 16401 456105 0 0 3 0x40014200 idle0 67306 483311 0 0 3 0x14200 bored smr 1 208777 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb> show all locks No such command ddb> show malloc Type InUse MemUse HighUse Limit Requests Type Lim Kern Lim devbuf 9591 6364K 7114K 78643K 13914 0 0 pcb 13 11K 13K 78643K 324 0 0 rtable 101 12K 13K 78643K 1248 0 0 ifaddr 87 17K 19K 78643K 364 0 0 counters 19 16K 16K 78643K 19 0 0 ioctlops 0 0K 2K 78643K 137 0 0 iov 0 0K 16K 78643K 409 0 0 mount 1 1K 1K 78643K 1 0 0 vnodes 1223 77K 77K 78643K 2661 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 34 0 0 VM map 11 2K 3K 78643K 18 0 0 sem 12 1K 1K 78643K 66 0 0 dirhash 12 2K 2K 78643K 12 0 0 ACPI 1793 195K 288K 78643K 12645 0 0 file desc 4 9K 25K 78643K 1578 0 0 sigio 0 0K 0K 78643K 34 0 0 proc 49 38K 55K 78643K 976 0 0 subproc 16 1K 2K 78643K 238 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 94 0 0 in_multi 21 1K 2K 78643K 268 0 0 ether_multi 1 0K 0K 78643K 26 0 0 mrt 0 0K 0K 78643K 4 0 0 ISOFS mount 1 32K 32K 78643K 1 0 0 MSDOSFS mount 1 16K 16K 78643K 1 0 0 ttys 150 662K 662K 78643K 150 0 0 exec 0 0K 1K 78643K 483 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 116 95K 112K 78643K 5007 0 0 UVM aobj 111 3K 4K 78643K 146 0 0 memdesc 1 4K 4K 78643K 1 0 0 crypto data 1 1K 1K 78643K 1 0 0 ip6_options 0 0K 0K 78643K 291 0 0 NDP 22 0K 0K 78643K 117 0 0 temp 224 3544K 3673K 78643K 84422 0 0 kqueue 0 0K 0K 78643K 22 0 0 SYN cache 2 16K 16K 78643K 2 0 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 35 0 30 1 0 1 1 0 8 0 rtpcb 80 253 0 251 1 0 1 1 0 8 0 rtentry 112 217 0 184 2 0 2 2 0 8 0 unpcb 120 943 0 935 2 1 1 2 0 8 0 syncache 264 12 0 12 4 4 0 1 0 8 0 tcpqe 32 37 0 37 3 3 0 1 0 8 0 tcpcb 544 757 0 753 16 15 1 15 0 8 0 ipq 40 899 0 899 3 2 1 1 0 8 1 ipqe 40 1977 0 1977 3 2 1 1 0 8 1 inpcb 280 3390 0 3381 17 15 2 9 0 8 1 rttmr 72 1 0 1 1 1 0 1 0 8 0 nd6 48 32 0 31 3 2 1 1 0 8 0 pkpcb 40 4 0 4 2 2 0 1 0 8 0 swfcl 56 2 0 0 1 0 1 1 0 8 0 ppxss 1128 36 0 36 8 7 1 1 0 8 1 art_heap8 4096 8 0 7 6 5 1 3 0 8 0 art_heap4 256 999 0 827 25 13 12 17 0 8 0 art_table 32 1007 0 834 3 1 2 3 0 8 0 art_node 16 216 0 182 1 0 1 1 0 8 0 sysvmsgpl 40 18 0 15 1 0 1 1 0 8 0 semupl 112 3 0 3 1 1 0 1 0 8 0 semapl 112 64 0 54 1 0 1 1 0 8 0 shmpl 112 144 0 35 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 3739 0 2345 46 0 46 46 0 8 0 ffsino 240 3739 0 2345 83 0 83 83 0 8 0 nchpl 144 6108 0 5618 60 41 19 60 0 8 0 uvmvnodes 72 4846 0 0 89 0 89 89 0 8 0 vnodes 208 4846 0 0 256 0 256 256 0 8 0 namei 1024 21772 0 21772 2 1 1 1 0 8 1 vcpupl 1984 10 0 1 2 0 2 2 0 8 0 vmpool 520 16 0 7 1 0 1 1 0 8 0 scsiplug 64 2 0 2 1 1 0 1 0 8 0 scxspl 192 19907 0 19907 14 13 1 7 0 8 1 plimitpl 152 162 0 156 1 0 1 1 0 8 0 sigapl 432 1714 0 1702 2 0 2 2 0 8 0 futexpl 56 45566 0 45566 2 1 1 1 0 8 1 knotepl 112 724 0 711 3 1 2 2 0 8 1 kqueuepl 104 667 0 665 4 3 1 4 0 8 0 pipepl 112 1926 0 1913 11 9 2 2 0 8 1 fdescpl 424 1715 0 1702 2 0 2 2 0 8 0 filepl 120 16655 0 16581 20 16 4 10 0 8 0 lockfpl 104 587 0 586 1 0 1 1 0 8 0 lockfspl 48 199 0 198 1 0 1 1 0 8 0 sessionpl 112 30 0 21 1 0 1 1 0 8 0 pgrppl 48 52 0 43 1 0 1 1 0 8 0 ucredpl 96 2806 0 2799 1 0 1 1 0 8 0 zombiepl 144 1703 0 1703 2 1 1 1 0 8 1 processpl 864 1731 0 1703 4 0 4 4 0 8 0 procpl 632 3720 0 3684 4 0 4 4 0 8 0 sosppl 128 19 0 19 6 5 1 1 0 8 1 sockpl 384 4646 0 4627 27 23 4 14 0 8 2 mcl64k 65536 203 0 203 4 3 1 1 0 8 1 mcl16k 16384 63 0 63 6 5 1 1 0 8 1 mcl12k 12288 72 0 72 5 5 0 1 0 8 0 mcl9k 9216 57 0 57 6 5 1 1 0 8 1 mcl8k 8192 335 0 335 4 3 1 1 0 8 1 mcl4k 4096 140 0 140 5 4 1 1 0 8 1 mcl2k2 2112 4 0 4 4 4 0 1 0 8 0 mcl2k 2048 70837 0 70795 25 19 6 13 0 8 0 mtagpl 80 69 0 66 5 4 1 1 0 8 0 mbufpl 256 135937 0 135857 61 50 11 25 0 8 2 bufpl 256 11588 0 6370 332 5 327 327 0 8 0 anonpl 16 231037 0 216707 130 48 82 93 0 62 5 amapchunkpl 152 10004 0 9897 44 34 10 19 0 158 4 amappl16 192 9915 0 8856 107 51 56 66 0 8 2 amappl15 184 17 0 17 3 3 0 1 0 8 0 amappl14 176 589 0 586 1 0 1 1 0 8 0 amappl13 168 150 0 149 5 4 1 1 0 8 0 amappl12 160 9 0 7 1 0 1 1 0 8 0 amappl11 152 407 0 396 1 0 1 1 0 8 0 amappl10 144 253 0 250 1 0 1 1 0 8 0 amappl9 136 904 0 896 1 0 1 1 0 8 0 amappl8 128 441 0 405 3 1 2 2 0 8 0 amappl7 120 333 0 325 1 0 1 1 0 8 0 amappl6 112 390 0 379 1 0 1 1 0 8 0 amappl5 104 302 0 293 1 0 1 1 0 8 0 amappl4 96 2067 0 2039 1 0 1 1 0 8 0 amappl3 88 404 0 398 1 0 1 1 0 8 0 amappl2 80 12385 0 12321 3 1 2 3 0 8 0 amappl1 72 42164 0 41761 26 16 10 20 0 8 0 amappl 80 4152 0 4112 4 2 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 64 145 0 35 2 0 2 2 0 8 0 uaddrrnd 24 1731 0 1702 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1731 0 1702 1 0 1 1 0 8 0 vmmpekpl 168 16965 0 16938 2 0 2 2 0 8 0 vmmpepl 168 217666 0 215600 230 102 128 141 0 357 29 vmsppl 272 1714 0 1702 5 4 1 2 0 8 0 pdppl 4096 3468 0 3427 7 1 6 6 0 8 0 pvpl 32 583201 0 565893 268 74 194 215 0 265 15 pmappl 200 1730 0 1709 2 0 2 2 0 8 0 extentpl 40 41 0 26 1 0 1 1 0 8 0 phpool 112 586 0 130 14 0 14 14 0 8 0