login: panic: m_copym0: short mbuf chain Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *121272 32362 0 0x12 0 0 sshd db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff823cb330) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd8066555e00,40c,20c,2) at m_copym+0x553 sys/kern/uipc_mbuf.c:695 tcp_output(ffff800000ac2320) at tcp_output+0x154d sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd805da73008,9,fffffd8066555d00,0,0,ffff80001d71c760) at tcp_usrreq+0xa54 sosend(fffffd805da73008,0,ffff80001d7236d8,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:555 dofilewritev(ffff80001d71c760,4,ffff80001d7236d8,0,ffff80001d7237c0) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d71c760,ffff80001d723770,ffff80001d7237c0) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d723840) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffc7520, 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(ffffffff823cb330) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd8066555e00,40c,20c,2) at m_copym+0x553 sys/kern/uipc_mbuf.c:695 tcp_output(ffff800000ac2320) at tcp_output+0x154d sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd805da73008,9,fffffd8066555d00,0,0,ffff80001d71c760) at tcp_usrreq+0xa54 sosend(fffffd805da73008,0,ffff80001d7236d8,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:555 dofilewritev(ffff80001d71c760,4,ffff80001d7236d8,0,ffff80001d7237c0) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d71c760,ffff80001d723770,ffff80001d7237c0) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d723840) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffc7520, count: -10 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff80001d7231a0 rbx 0xffff80001d723250 rdx 0x2 rcx 0 rax 0x1 r8 0xffffffff81b03daf kprintf+0x15f r9 0x1 r10 0x2 r11 0xc81d3a06f0a015ed r12 0x3000000008 r13 0xffff80001d7231b0 r14 0x100 r15 0x1 rip 0xffffffff81f9d8f8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff80001d723190 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (sshd) pid=121272 stat=onproc flags process=12 proc=0 pri=24, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff80001d71d600,0xffff80001d71c290 process=0xffff80001d706e98 user=0xffff80001d71e000, vmspace=0xfffffd806bc0a770 estcpu=0, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 48020 521289 11357 0 2 0 syz-executor.0 48020 225248 11357 0 2 0x4000000 syz-executor.0 55323 391748 0 0 3 0x14200 acct acct 71478 455290 87816 0 2 0x2 syz-executor.1 11357 175358 87816 0 3 0x82 nanosleep syz-executor.0 87816 337431 3560 0 3 0x82 thrsleep syz-fuzzer 87816 499318 3560 0 3 0x4000082 nanosleep syz-fuzzer 87816 349586 3560 0 2 0x4000002 syz-fuzzer 87816 114921 3560 0 3 0x4000082 thrsleep syz-fuzzer 87816 116177 3560 0 3 0x4000082 thrsleep syz-fuzzer 87816 58356 3560 0 3 0x4000082 thrsleep syz-fuzzer 87816 232808 3560 0 3 0x4000082 thrsleep syz-fuzzer 3560 210013 32362 0 3 0x10008a pause ksh *32362 121272 13862 0 7 0x12 sshd 94917 480157 1 0 3 0x100083 ttyin getty 13862 504008 1 0 3 0x80 select sshd 44076 497734 46631 73 3 0x100090 kqread syslogd 46631 457799 1 0 3 0x100082 netio syslogd 70020 490396 1 77 3 0x100090 poll dhclient 78448 24376 1 0 3 0x80 poll dhclient 23653 185444 0 0 3 0x14200 bored smr 88007 53177 0 0 2 0x14200 zerothread 11303 44382 0 0 3 0x14200 aiodoned aiodoned 33102 475589 0 0 3 0x14200 syncer update 79941 63465 0 0 3 0x14200 cleaner cleaner 98233 441127 0 0 3 0x14200 reaper reaper 44656 144125 0 0 3 0x14200 pgdaemon pagedaemon 77141 60460 0 0 3 0x14200 bored crynlk 31464 407068 0 0 3 0x14200 bored crypto 51589 74126 0 0 3 0x40014200 acpi0 acpi0 23442 13620 0 0 3 0x14200 bored softnet 93030 355817 0 0 3 0x14200 bored systqmp 50505 131625 0 0 3 0x14200 bored systq 31893 484692 0 0 3 0x40014200 bored softclock 81383 394 0 0 3 0x40014200 idle0 1 256213 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 9457 6327K 6453K 78643K 10578 0 pcb 13 8K 8K 78643K 27 0 rtable 106 3K 7K 78643K 248 0 ifaddr 44 10K 11K 78643K 62 0 counters 21 16K 16K 78643K 21 0 ioctlops 0 0K 4K 78643K 19 0 iov 0 0K 2K 78643K 4 0 mount 1 1K 1K 78643K 1 0 vnodes 1216 76K 77K 78643K 1227 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 2 0K 0K 78643K 2 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 195K 288K 78643K 12938 0 file desc 5 13K 25K 78643K 54 0 proc 48 38K 54K 78643K 359 0 subproc 32 2K 2K 78643K 34 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 in_multi 33 2K 2K 78643K 33 0 ether_multi 1 0K 0K 78643K 1 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 31 148K 148K 78643K 31 0 exec 0 0K 1K 78643K 181 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 113 22K 23K 78643K 958 0 UVM aobj 5 2K 2K 78643K 5 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 2 0 NDP 6 0K 0K 78643K 10 0 temp 67 3848K 3912K 78643K 1864 0 kqueue 3 4K 4K 78643K 3 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 32 465 0 465 2 2 0 1 0 8 0 tcpcb 544 15 0 11 1 0 1 1 0 8 0 inpcb 296 52 0 45 1 0 1 1 0 8 0 nd6 48 6 0 0 1 0 1 1 0 8 0 pfrktable 1344 28 0 28 2 1 1 1 0 8 1 pftag 88 4 0 4 1 1 0 1 0 8 0 pfrule 1360 4 0 4 2 1 1 1 0 8 1 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 187 0 0 12 0 12 12 0 8 0 art_table 32 188 0 0 2 0 2 2 0 8 0 art_node 16 44 0 4 1 0 1 1 0 8 0 shmpl 112 2 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1447 0 49 88 0 88 88 0 8 0 ffsino 240 1447 0 49 83 0 83 83 0 8 0 nchpl 144 1700 0 97 60 0 60 60 0 8 0 uvmvnodes 72 1494 0 0 28 0 28 28 0 8 0 vnodes 208 1494 0 0 79 0 79 79 0 8 0 namei 1024 4201 0 4201 1 0 1 1 0 8 1 pfiaddrpl 120 8 0 8 2 1 1 1 0 8 1 scxspl 192 4867 0 4867 1 0 1 1 0 8 1 plimitpl 152 16 0 9 1 0 1 1 0 8 0 sigapl 424 241 0 212 4 0 4 4 0 8 0 futexpl 56 495 0 495 1 0 1 1 0 8 1 knotepl 112 61 0 42 1 0 1 1 0 8 0 kqueuepl 144 2 0 0 1 0 1 1 0 8 0 pipepl 272 68 0 58 1 0 1 1 0 8 0 fdescpl 432 226 0 212 2 0 2 2 0 8 0 filepl 120 1139 0 1044 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 64 0 57 1 0 1 1 0 8 0 zombiepl 144 212 0 212 1 0 1 1 0 8 1 processpl 928 241 0 212 4 0 4 4 0 8 0 procpl 624 279 0 243 4 0 4 4 0 8 1 sockpl 400 124 0 107 3 0 3 3 0 8 1 mcl16k 16384 2 0 2 2 1 1 1 0 8 1 mcl8k 8192 4 0 4 2 1 1 1 0 8 1 mcl4k 4096 8 0 8 1 1 0 1 0 8 0 mcl2k 2048 76241 0 76182 19 7 12 17 0 8 2 mtagpl 96 4 0 2 2 1 1 1 0 8 0 mbufpl 256 121066 0 120966 15 4 11 11 0 8 1 bufpl 280 3297 0 126 227 0 227 227 0 8 0 anonpl 16 41965 0 26098 80 2 78 78 0 107 13 amapchunkpl 152 1011 0 870 8 1 7 8 0 158 0 amappl16 192 1266 0 413 53 0 53 53 0 8 10 amappl15 184 1 0 0 1 0 1 1 0 8 0 amappl14 176 33 0 26 1 0 1 1 0 8 0 amappl13 168 26 0 23 1 0 1 1 0 8 0 amappl12 160 16 0 12 1 0 1 1 0 8 0 amappl11 152 55 0 45 1 0 1 1 0 8 0 amappl10 144 16 0 12 1 0 1 1 0 8 0 amappl9 136 369 0 367 1 0 1 1 0 8 0 amappl8 128 313 0 276 2 0 2 2 0 8 0 amappl7 120 107 0 95 1 0 1 1 0 8 0 amappl6 112 33 0 28 1 0 1 1 0 8 0 amappl5 104 185 0 174 1 0 1 1 0 8 0 amappl4 96 418 0 395 1 0 1 1 0 8 0 amappl3 88 108 0 100 1 0 1 1 0 8 0 amappl2 80 940 0 875 2 0 2 2 0 8 0 amappl1 72 13946 0 13529 23 13 10 17 0 8 0 amappl 80 499 0 459 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 4 0 0 1 0 1 1 0 8 0 uaddrrnd 24 226 0 212 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 226 0 212 1 0 1 1 0 8 0 vmmpekpl 168 5715 0 5688 2 0 2 2 0 8 0 vmmpepl 168 35559 0 33611 124 8 116 119 0 357 31 vmsppl 272 225 0 212 2 1 1 2 0 8 0 pdppl 4096 458 0 424 6 1 5 6 0 8 0 pvpl 32 133092 0 114275 184 0 184 184 0 265 32 pmappl 200 225 0 212 1 0 1 1 0 8 0 extentpl 40 53 0 36 1 0 1 1 0 8 0 phpool 112 248 0 19 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(ffffffff823cb330) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd8066555e00,40c,20c,2) at m_copym+0x553 sys/kern/uipc_mbuf.c:695 tcp_output(ffff800000ac2320) at tcp_output+0x154d sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd805da73008,9,fffffd8066555d00,0,0,ffff80001d71c760) at tcp_usrreq+0xa54 sosend(fffffd805da73008,0,ffff80001d7236d8,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:555 dofilewritev(ffff80001d71c760,4,ffff80001d7236d8,0,ffff80001d7237c0) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d71c760,ffff80001d723770,ffff80001d7237c0) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d723840) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffc7520, 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(ffffffff823cb330) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd8066555e00,40c,20c,2) at m_copym+0x553 sys/kern/uipc_mbuf.c:695 tcp_output(ffff800000ac2320) at tcp_output+0x154d sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd805da73008,9,fffffd8066555d00,0,0,ffff80001d71c760) at tcp_usrreq+0xa54 sosend(fffffd805da73008,0,ffff80001d7236d8,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:555 dofilewritev(ffff80001d71c760,4,ffff80001d7236d8,0,ffff80001d7237c0) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d71c760,ffff80001d723770,ffff80001d7237c0) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d723840) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffc7520, count: -10