login: panic: m_copym0: short mbuf chain Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND * 31355 81340 0 0x12 0 0 sshd db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff823b45c7) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd805851f600,38c,2ec,2) at m_copym+0x553 sys/kern/uipc_mbuf.c:695 tcp_output(ffff800000abfee0) at tcp_output+0x154d sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd805da684b8,9,fffffd805851f100,0,0,ffff80001d717c40) at tcp_usrreq+0xa54 sosend(fffffd805da684b8,0,ffff80001d6cac18,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:549 dofilewritev(ffff80001d717c40,4,ffff80001d6cac18,0,ffff80001d6cad00) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d717c40,ffff80001d6cacb0,ffff80001d6cad00) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d6cad80) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffc02f0, count: 5 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 m_copym0: short mbuf chain ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff823b45c7) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd805851f600,38c,2ec,2) at m_copym+0x553 sys/kern/uipc_mbuf.c:695 tcp_output(ffff800000abfee0) at tcp_output+0x154d sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd805da684b8,9,fffffd805851f100,0,0,ffff80001d717c40) at tcp_usrreq+0xa54 sosend(fffffd805da684b8,0,ffff80001d6cac18,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:549 dofilewritev(ffff80001d717c40,4,ffff80001d6cac18,0,ffff80001d6cad00) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d717c40,ffff80001d6cacb0,ffff80001d6cad00) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d6cad80) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffc02f0, count: -10 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff80001d6ca6e0 rbx 0xffff80001d6ca790 rdx 0x2 rcx 0 rax 0x1 r8 0xffffffff821959cf kprintf+0x15f r9 0x1 r10 0x2 r11 0xb36335e2b089bb13 r12 0x3000000008 r13 0xffff80001d6ca6f0 r14 0x100 r15 0x1 rip 0xffffffff81e0dea8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff80001d6ca6d0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (sshd) pid=31355 stat=onproc flags process=12 proc=0 pri=24, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff80001d718390,0xffff80001d717500 process=0xffff8000ffff8018 user=0xffff80001d6c5000, vmspace=0xfffffd806bc0a550 estcpu=0, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 40347 321063 70664 0 2 0x2 syz-executor.0 12781 523800 70664 0 2 0x2 syz-executor.1 70664 485697 80514 0 3 0x82 thrsleep syz-fuzzer 70664 101225 80514 0 2 0x4000002 syz-fuzzer 70664 68919 80514 0 3 0x4000082 thrsleep syz-fuzzer 70664 92219 80514 0 3 0x4000082 thrsleep syz-fuzzer 70664 218310 80514 0 2 0x4000002 syz-fuzzer 70664 297343 80514 0 3 0x4000082 thrsleep syz-fuzzer 70664 376528 80514 0 3 0x4000082 thrsleep syz-fuzzer 80514 23915 81340 0 3 0x10008a pause ksh *81340 31355 32324 0 7 0x12 sshd 47848 207350 1 0 3 0x100083 ttyin getty 32324 421752 1 0 3 0x80 select sshd 92798 50995 74354 73 3 0x100090 kqread syslogd 74354 372006 1 0 3 0x100082 netio syslogd 7504 251204 1 77 3 0x100090 poll dhclient 80971 7515 1 0 3 0x80 poll dhclient 36168 42326 0 0 3 0x14200 bored smr 76118 88442 0 0 3 0x14200 pgzero zerothread 34861 39084 0 0 3 0x14200 aiodoned aiodoned 83644 370389 0 0 3 0x14200 syncer update 8369 510497 0 0 3 0x14200 cleaner cleaner 95670 58711 0 0 3 0x14200 reaper reaper 45399 162763 0 0 3 0x14200 pgdaemon pagedaemon 13679 348635 0 0 3 0x14200 bored crynlk 29079 286924 0 0 3 0x14200 bored crypto 73213 260688 0 0 3 0x40014200 acpi0 acpi0 86098 482639 0 0 3 0x14200 bored softnet 47131 367402 0 0 3 0x14200 bored systqmp 87988 237452 0 0 3 0x14200 bored systq 29239 211385 0 0 3 0x40014200 bored softclock 95900 256963 0 0 3 0x40014200 idle0 1 305324 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 devbuf 9473 6340K 6461K 78643K 10609 0 pcb 13 8K 8K 78643K 65 0 rtable 105 3K 3K 78643K 197 0 ifaddr 52 11K 11K 78643K 55 0 counters 21 16K 16K 78643K 21 0 ioctlops 0 0K 2K 78643K 19 0 iov 0 0K 12K 78643K 12 0 mount 1 1K 1K 78643K 1 0 vnodes 1218 77K 77K 78643K 1234 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 3 0 VM map 2 0K 0K 78643K 2 0 sem 11 0K 1K 78643K 18 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 195K 288K 78643K 12938 0 file desc 4 9K 25K 78643K 66 0 proc 49 38K 54K 78643K 363 0 subproc 32 2K 2K 78643K 34 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 3 0 in_multi 33 2K 2K 78643K 38 0 ether_multi 1 0K 0K 78643K 3 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 43 201K 201K 78643K 43 0 exec 0 0K 1K 78643K 185 0 pagedep 1 8K 8K 78643K 1 0 inodedep 1 32K 32K 78643K 1 0 newblk 1 0K 0K 78643K 1 0 VM swap 7 26K 26K 78643K 7 0 UVM amap 118 22K 38K 78643K 998 0 UVM aobj 2 2K 2K 78643K 2 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 12 0 NDP 8 0K 0K 78643K 12 0 temp 73 3839K 3903K 78643K 1854 0 kqueue 3 4K 8K 78643K 5 0 SYN cache 2 16K 16K 78643K 2 0 ddb> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 6 0 0 1 0 1 1 0 8 0 rtpcb 80 19 0 17 1 0 1 1 0 8 0 rtentry 112 45 0 1 2 0 2 2 0 8 0 unpcb 120 53 0 45 1 0 1 1 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpqe 32 632 0 632 1 0 1 1 0 8 1 tcpcb 544 20 0 16 1 0 1 1 0 8 0 inpcb 280 112 0 105 2 0 2 2 0 8 1 nd6 48 6 0 0 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 188 0 0 12 0 12 12 0 8 0 art_table 32 189 0 0 2 0 2 2 0 8 0 art_node 16 44 0 4 1 0 1 1 0 8 0 sysvmsgpl 40 4 0 4 1 0 1 1 0 8 1 semupl 112 1 0 1 1 0 1 1 0 8 1 semapl 112 10 0 1 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1462 0 64 88 0 88 88 0 8 0 ffsino 240 1462 0 64 83 0 83 83 0 8 0 nchpl 144 1732 0 131 60 0 60 60 0 8 0 uvmvnodes 72 1514 0 0 28 0 28 28 0 8 0 vnodes 208 1514 0 0 80 0 80 80 0 8 0 namei 1024 4312 0 4312 2 1 1 1 0 8 1 scxspl 192 5023 0 5023 1 0 1 1 0 8 1 plimitpl 152 16 0 9 1 0 1 1 0 8 0 sigapl 424 252 0 225 4 0 4 4 0 8 0 futexpl 56 799 0 799 1 0 1 1 0 8 1 knotepl 112 63 0 44 1 0 1 1 0 8 0 kqueuepl 144 6 0 4 1 0 1 1 0 8 0 pipepl 272 74 0 64 1 0 1 1 0 8 0 fdescpl 432 238 0 225 2 0 2 2 0 8 0 filepl 120 1244 0 1149 4 0 4 4 0 8 1 lockfpl 104 5 0 4 1 0 1 1 0 8 0 lockfspl 48 3 0 2 1 0 1 1 0 8 0 sessionpl 112 17 0 7 1 0 1 1 0 8 0 pgrppl 48 17 0 7 1 0 1 1 0 8 0 ucredpl 96 68 0 61 1 0 1 1 0 8 0 zombiepl 144 225 0 225 2 1 1 1 0 8 1 processpl 920 252 0 225 4 0 4 4 0 8 0 procpl 624 296 0 263 4 0 4 4 0 8 1 sockpl 400 186 0 169 3 0 3 3 0 8 1 mcl64k 65536 12 0 12 1 0 1 1 0 8 1 mcl12k 12288 3 0 3 1 0 1 1 0 8 1 mcl4k 4096 13 0 13 2 1 1 1 0 8 1 mcl2k 2048 71077 0 71019 21 6 15 18 0 8 6 mtagpl 80 6 0 2 2 1 1 1 0 8 0 mbufpl 256 113225 0 113138 13 2 11 11 0 8 1 bufpl 280 3307 0 126 228 0 228 228 0 8 0 anonpl 16 38089 0 23084 63 2 61 61 0 107 0 amapchunkpl 152 1827 0 1699 19 0 19 19 0 158 12 amappl16 192 1064 0 247 42 0 42 42 0 8 1 amappl15 184 26 0 23 1 0 1 1 0 8 0 amappl14 176 26 0 19 1 0 1 1 0 8 0 amappl13 168 26 0 23 1 0 1 1 0 8 0 amappl12 160 9 0 8 1 0 1 1 0 8 0 amappl11 152 61 0 51 1 0 1 1 0 8 0 amappl10 144 15 0 10 1 0 1 1 0 8 0 amappl9 136 375 0 373 1 0 1 1 0 8 0 amappl8 128 341 0 302 2 0 2 2 0 8 0 amappl7 120 109 0 95 1 0 1 1 0 8 0 amappl6 112 23 0 20 1 0 1 1 0 8 0 amappl5 104 199 0 188 1 0 1 1 0 8 0 amappl4 96 418 0 394 1 0 1 1 0 8 0 amappl3 88 105 0 98 1 0 1 1 0 8 0 amappl2 80 1099 0 1040 2 0 2 2 0 8 0 amappl1 72 14098 0 13706 23 9 14 17 0 8 4 amappl 80 528 0 489 1 0 1 1 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 1 0 0 1 0 1 1 0 8 0 uaddrrnd 24 238 0 225 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 238 0 225 1 0 1 1 0 8 0 vmmpekpl 168 5811 0 5789 2 0 2 2 0 8 0 vmmpepl 168 36029 0 34239 150 7 143 143 0 357 59 vmsppl 272 237 0 225 2 0 2 2 0 8 1 pdppl 4096 482 0 450 6 0 6 6 0 8 1 pvpl 32 130721 0 112839 151 0 151 151 0 265 4 pmappl 200 237 0 225 1 0 1 1 0 8 0 extentpl 40 53 0 36 1 0 1 1 0 8 0 phpool 112 245 0 12 7 0 7 7 0 8 0 ddb> machine ddbcpu 0 No such command ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff823b45c7) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd805851f600,38c,2ec,2) at m_copym+0x553 sys/kern/uipc_mbuf.c:695 tcp_output(ffff800000abfee0) at tcp_output+0x154d sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd805da684b8,9,fffffd805851f100,0,0,ffff80001d717c40) at tcp_usrreq+0xa54 sosend(fffffd805da684b8,0,ffff80001d6cac18,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:549 dofilewritev(ffff80001d717c40,4,ffff80001d6cac18,0,ffff80001d6cad00) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d717c40,ffff80001d6cacb0,ffff80001d6cad00) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d6cad80) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffc02f0, count: -10 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff823b45c7) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd805851f600,38c,2ec,2) at m_copym+0x553 sys/kern/uipc_mbuf.c:695 tcp_output(ffff800000abfee0) at tcp_output+0x154d sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd805da684b8,9,fffffd805851f100,0,0,ffff80001d717c40) at tcp_usrreq+0xa54 sosend(fffffd805da684b8,0,ffff80001d6cac18,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:549 dofilewritev(ffff80001d717c40,4,ffff80001d6cac18,0,ffff80001d6cad00) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d717c40,ffff80001d6cacb0,ffff80001d6cad00) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d6cad80) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffc02f0, count: -10