panic: m_copym0: m == NULL and not COPYALL Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *451216 33704 0 0x12 0 0 sshd db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff8242606d) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd80594a4300,ac4,1d4,2) at m_copym+0x589 sys/kern/uipc_mbuf.c:664 tcp_output(ffff800000ac2320) at tcp_output+0x154d sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd805da5d4b8,9,fffffd80594a4200,0,0,ffff80001d717760) at tcp_usrreq+0xa54 sosend(fffffd805da5d4b8,0,ffff80001d71ea88,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:555 dofilewritev(ffff80001d717760,4,ffff80001d71ea88,0,ffff80001d71eb70) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d717760,ffff80001d71eb20,ffff80001d71eb70) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d71ebf0) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffcf620, 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: m == NULL and not COPYALL ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff8242606d) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd80594a4300,ac4,1d4,2) at m_copym+0x589 sys/kern/uipc_mbuf.c:664 tcp_output(ffff800000ac2320) at tcp_output+0x154d sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd805da5d4b8,9,fffffd80594a4200,0,0,ffff80001d717760) at tcp_usrreq+0xa54 sosend(fffffd805da5d4b8,0,ffff80001d71ea88,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:555 dofilewritev(ffff80001d717760,4,ffff80001d71ea88,0,ffff80001d71eb70) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d717760,ffff80001d71eb20,ffff80001d71eb70) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d71ebf0) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffcf620, count: -10 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff80001d71e550 rbx 0xffff80001d71e600 rdx 0x2 rcx 0 rax 0x1 r8 0xffffffff8139b17f kprintf+0x15f r9 0x1 r10 0x2 r11 0x5f5edf24fdd9300e r12 0x3000000008 r13 0xffff80001d71e560 r14 0x100 r15 0x1 rip 0xffffffff8171c378 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff80001d71e540 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (sshd) pid=451216 stat=onproc flags process=12 proc=0 pri=24, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff80001d718870,0xffff80001d717290 process=0xffff8000ffff8e78 user=0xffff80001d719000, vmspace=0xfffffd806bc09990 estcpu=0, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 8703 136058 86587 0 2 0x2 syz-executor.1 87022 19395 86587 0 2 0x2 syz-executor.0 86587 188190 84666 0 3 0x82 thrsleep syz-fuzzer 86587 207150 84666 0 2 0x4000002 syz-fuzzer 86587 195477 84666 0 3 0x4000082 thrsleep syz-fuzzer 86587 103826 84666 0 3 0x4000082 thrsleep syz-fuzzer 86587 444506 84666 0 2 0x4000002 syz-fuzzer 86587 55461 84666 0 3 0x4000082 thrsleep syz-fuzzer 86587 472545 84666 0 3 0x4000082 thrsleep syz-fuzzer 84666 384230 33704 0 3 0x10008a pause ksh *33704 451216 62605 0 7 0x12 sshd 92709 72998 1 0 3 0x100083 ttyin getty 62605 165069 1 0 3 0x80 select sshd 89136 428893 21317 73 3 0x100090 kqread syslogd 21317 105204 1 0 3 0x100082 netio syslogd 90010 478474 1 77 3 0x100090 poll dhclient 62056 33211 1 0 3 0x80 poll dhclient 59358 514033 0 0 3 0x14200 bored smr 93531 327461 0 0 3 0x14200 pgzero zerothread 78141 70320 0 0 3 0x14200 aiodoned aiodoned 50699 477828 0 0 3 0x14200 syncer update 66490 510215 0 0 3 0x14200 cleaner cleaner 94377 159840 0 0 3 0x14200 reaper reaper 31115 417617 0 0 3 0x14200 pgdaemon pagedaemon 80767 124328 0 0 3 0x14200 bored crynlk 9054 292914 0 0 3 0x14200 bored crypto 35964 304752 0 0 3 0x40014200 acpi0 acpi0 86160 404624 0 0 2 0x14200 softnet 16761 189169 0 0 3 0x14200 bored systqmp 75021 364439 0 0 3 0x14200 bored systq 40676 439441 0 0 3 0x40014200 bored softclock 78464 322264 0 0 3 0x40014200 idle0 1 101690 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 9466 6330K 6459K 78643K 10618 0 pcb 13 8K 8K 78643K 33 0 rtable 108 3K 4K 78643K 208 0 ifaddr 48 11K 11K 78643K 56 0 counters 21 16K 16K 78643K 21 0 ioctlops 0 0K 4K 78643K 27 0 iov 0 0K 4K 78643K 34 0 mount 1 1K 1K 78643K 1 0 vnodes 1218 77K 77K 78643K 1235 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 4 0K 0K 78643K 4 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 195K 288K 78643K 12938 0 file desc 4 9K 25K 78643K 72 0 proc 49 38K 63K 78643K 365 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 62 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 38K 40K 78643K 1040 0 UVM aobj 4 2K 2K 78643K 4 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 16 0 NDP 7 0K 0K 78643K 17 0 temp 78 3849K 3913K 78643K 1875 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 51 0 7 2 0 2 2 0 8 0 unpcb 120 47 0 39 1 0 1 1 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 sackhl 24 1 0 1 1 1 0 1 0 8 0 tcpqe 32 125 0 125 1 1 0 1 0 8 0 tcpcb 544 34 0 30 1 0 1 1 0 8 0 inpcb 296 88 0 81 2 0 2 2 0 8 1 nd6 48 12 0 6 1 0 1 1 0 8 0 pfrktable 1344 1 0 0 1 0 1 1 0 8 0 pfrule 1360 6 0 2 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 50 0 10 1 0 1 1 0 8 0 sysvmsgpl 40 14 0 3 1 0 1 1 0 8 0 semapl 112 2 0 0 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 1467 0 69 88 0 88 88 0 8 0 ffsino 240 1467 0 69 83 0 83 83 0 8 0 nchpl 144 1757 0 154 60 0 60 60 0 8 0 uvmvnodes 72 1520 0 0 28 0 28 28 0 8 0 vnodes 208 1520 0 0 80 0 80 80 0 8 0 namei 1024 4390 0 4389 1 0 1 1 0 8 0 vcpupl 1984 2 0 0 1 0 1 1 0 8 0 vmpool 528 2 0 0 1 0 1 1 0 8 0 scxspl 192 5154 0 5154 1 0 1 1 0 8 1 plimitpl 152 17 0 10 1 0 1 1 0 8 0 sigapl 424 258 0 231 4 0 4 4 0 8 0 futexpl 56 934 0 934 1 0 1 1 0 8 1 knotepl 112 61 0 42 1 0 1 1 0 8 0 kqueuepl 144 12 0 10 1 0 1 1 0 8 0 pipelkpl 16 73 0 63 1 0 1 1 0 8 0 pipepl 120 146 0 127 1 0 1 1 0 8 0 fdescpl 432 244 0 231 2 0 2 2 0 8 0 filepl 120 1284 0 1189 4 0 4 4 0 8 1 lockfpl 104 13 0 12 1 0 1 1 0 8 0 lockfspl 48 6 0 5 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 96 111 0 104 1 0 1 1 0 8 0 zombiepl 144 231 0 231 1 0 1 1 0 8 1 processpl 920 258 0 231 4 0 4 4 0 8 0 procpl 624 336 0 303 4 0 4 4 0 8 1 sockpl 400 154 0 137 3 0 3 3 0 8 1 mcl64k 65536 5 0 5 1 0 1 1 0 8 1 mcl12k 12288 2 0 2 1 0 1 1 0 8 1 mcl9k 9216 1 0 1 1 1 0 1 0 8 0 mcl8k 8192 4 0 4 1 0 1 1 0 8 1 mcl4k 4096 10 0 10 2 1 1 1 0 8 1 mcl2k 2048 77178 0 77117 23 13 10 19 0 8 1 mtagpl 96 8 0 2 2 1 1 1 0 8 0 mbufpl 256 122511 0 122356 15 3 12 12 0 8 0 bufpl 280 3444 0 126 237 0 237 237 0 8 0 anonpl 16 40848 0 24537 69 2 67 67 0 107 1 amapchunkpl 152 1345 0 1218 15 2 13 13 0 158 7 amappl16 192 1184 0 289 46 0 46 46 0 8 1 amappl15 184 2 0 1 1 0 1 1 0 8 0 amappl14 176 24 0 19 1 0 1 1 0 8 0 amappl13 168 26 0 23 1 0 1 1 0 8 0 amappl12 160 10 0 9 1 0 1 1 0 8 0 amappl11 152 45 0 34 1 0 1 1 0 8 0 amappl10 144 31 0 26 1 0 1 1 0 8 0 amappl9 136 379 0 378 1 0 1 1 0 8 0 amappl8 128 314 0 278 2 0 2 2 0 8 0 amappl7 120 115 0 101 1 0 1 1 0 8 0 amappl6 112 26 0 19 3 2 1 1 0 8 0 amappl5 104 167 0 158 1 0 1 1 0 8 0 amappl4 96 419 0 393 1 0 1 1 0 8 0 amappl3 88 106 0 99 1 0 1 1 0 8 0 amappl2 80 1121 0 1062 2 0 2 2 0 8 0 amappl1 72 14251 0 13856 23 13 10 17 0 8 0 amappl 80 572 0 533 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 3 0 0 1 0 1 1 0 8 0 uaddrrnd 24 246 0 231 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 246 0 231 1 0 1 1 0 8 0 vmmpekpl 168 5888 0 5863 2 0 2 2 0 8 0 vmmpepl 168 36916 0 35049 120 16 104 110 0 357 16 vmsppl 272 245 0 231 2 0 2 2 0 8 1 pdppl 4096 498 0 464 6 1 5 6 0 8 0 pvpl 32 137631 0 118456 163 0 163 163 0 265 7 pmappl 200 245 0 231 1 0 1 1 0 8 0 extentpl 40 53 0 36 1 0 1 1 0 8 0 phpool 112 249 0 20 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(ffffffff8242606d) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd80594a4300,ac4,1d4,2) at m_copym+0x589 sys/kern/uipc_mbuf.c:664 tcp_output(ffff800000ac2320) at tcp_output+0x154d sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd805da5d4b8,9,fffffd80594a4200,0,0,ffff80001d717760) at tcp_usrreq+0xa54 sosend(fffffd805da5d4b8,0,ffff80001d71ea88,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:555 dofilewritev(ffff80001d717760,4,ffff80001d71ea88,0,ffff80001d71eb70) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d717760,ffff80001d71eb20,ffff80001d71eb70) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d71ebf0) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffcf620, 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(ffffffff8242606d) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd80594a4300,ac4,1d4,2) at m_copym+0x589 sys/kern/uipc_mbuf.c:664 tcp_output(ffff800000ac2320) at tcp_output+0x154d sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd805da5d4b8,9,fffffd80594a4200,0,0,ffff80001d717760) at tcp_usrreq+0xa54 sosend(fffffd805da5d4b8,0,ffff80001d71ea88,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:555 dofilewritev(ffff80001d717760,4,ffff80001d71ea88,0,ffff80001d71eb70) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d717760,ffff80001d71eb20,ffff80001d71eb70) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d71ebf0) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffcf620, count: -10