panic: m_copym0: m == NULL and not COPYALL Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *363338 67724 0 0x12 0 0 sshd db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff8241bf9c) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd806994b800,184,33c,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(fffffd805da6e008,9,fffffd806994b700,0,0,ffff80001d7174f0) at tcp_usrreq+0xa54 sosend(fffffd805da6e008,0,ffff80001d6c9e48,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:555 dofilewritev(ffff80001d7174f0,4,ffff80001d6c9e48,0,ffff80001d6c9f30) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d7174f0,ffff80001d6c9ee0,ffff80001d6c9f30) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d6c9fb0) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7fffff4c10, 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(ffffffff8241bf9c) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd806994b800,184,33c,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(fffffd805da6e008,9,fffffd806994b700,0,0,ffff80001d7174f0) at tcp_usrreq+0xa54 sosend(fffffd805da6e008,0,ffff80001d6c9e48,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:555 dofilewritev(ffff80001d7174f0,4,ffff80001d6c9e48,0,ffff80001d6c9f30) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d7174f0,ffff80001d6c9ee0,ffff80001d6c9f30) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d6c9fb0) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7fffff4c10, count: -10 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff80001d6c9910 rbx 0xffff80001d6c99c0 rdx 0x2 rcx 0 rax 0x1 r8 0xffffffff819dd21f kprintf+0x15f r9 0x1 r10 0x2 r11 0x847c3333687c654a r12 0x3000000008 r13 0xffff80001d6c9920 r14 0x100 r15 0x1 rip 0xffffffff820d2da8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff80001d6c9900 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (sshd) pid=363338 stat=onproc flags process=12 proc=0 pri=24, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff80001d718ae0,0xffff80001d717020 process=0xffff8000ffff8748 user=0xffff80001d6c5000, vmspace=0xfffffd806bc09880 estcpu=0, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 92525 252931 40995 0 2 0 syz-executor.1 92525 194467 40995 0 2 0x4000000 syz-executor.1 40995 221343 75692 0 3 0x82 nanosleep syz-executor.1 14670 49551 75692 0 2 0x2 syz-executor.0 75692 491776 60336 0 2 0x2 syz-fuzzer 75692 113288 60336 0 2 0x4000002 syz-fuzzer 75692 370213 60336 0 3 0x4000082 thrsleep syz-fuzzer 75692 367397 60336 0 3 0x4000082 thrsleep syz-fuzzer 75692 23667 60336 0 3 0x4000082 thrsleep syz-fuzzer 75692 515814 60336 0 3 0x4000082 thrsleep syz-fuzzer 75692 465892 60336 0 3 0x4000082 thrsleep syz-fuzzer 75692 504453 60336 0 3 0x4000082 thrsleep syz-fuzzer 60336 217949 67724 0 3 0x10008a pause ksh *67724 363338 7588 0 7 0x12 sshd 77628 186524 1 0 3 0x100083 ttyin getty 7588 83687 1 0 3 0x80 select sshd 42470 59165 16068 73 3 0x100090 kqread syslogd 16068 420312 1 0 3 0x100082 netio syslogd 11950 268367 1 77 3 0x100090 poll dhclient 31340 172237 1 0 3 0x80 poll dhclient 38840 191393 0 0 3 0x14200 bored smr 86834 92076 0 0 2 0x14200 zerothread 96861 83154 0 0 3 0x14200 aiodoned aiodoned 52149 216585 0 0 3 0x14200 syncer update 23677 238539 0 0 3 0x14200 cleaner cleaner 88370 137489 0 0 3 0x14200 reaper reaper 82313 205142 0 0 3 0x14200 pgdaemon pagedaemon 87552 38666 0 0 3 0x14200 bored crynlk 90698 60592 0 0 3 0x14200 bored crypto 99384 448039 0 0 3 0x40014200 acpi0 acpi0 85093 192423 0 0 3 0x14200 bored softnet 83337 123373 0 0 3 0x14200 bored systqmp 98159 356520 0 0 3 0x14200 bored systq 77682 451681 0 0 3 0x40014200 bored softclock 26750 180917 0 0 3 0x40014200 idle0 1 306451 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 9495 6718K 6726K 78643K 10702 0 pcb 13 8K 8K 78643K 33 0 rtable 124 8K 8K 78643K 276 0 ifaddr 57 13K 13K 78643K 80 0 counters 21 16K 16K 78643K 23 0 ioctlops 0 0K 4K 78643K 25 0 iov 0 0K 12K 78643K 6 0 mount 1 1K 1K 78643K 1 0 vnodes 1220 77K 77K 78643K 1260 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 1K 78643K 2 0 VM map 2 0K 0K 78643K 2 0 sem 6 0K 0K 78643K 6 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 195K 288K 78643K 12938 0 file desc 5 13K 25K 78643K 81 0 sigio 0 0K 0K 78643K 2 0 proc 47 38K 54K 78643K 368 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 34 0 in_multi 33 2K 2K 78643K 84 0 ether_multi 1 0K 0K 78643K 7 0 mrt 0 0K 0K 78643K 2 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 25 122K 122K 78643K 25 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 119 22K 23K 78643K 1018 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 12 0 NDP 7 0K 0K 78643K 19 0 temp 75 3854K 3918K 78643K 7765 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 21 0 19 1 0 1 1 0 8 0 rtentry 112 63 0 20 2 0 2 2 0 8 0 unpcb 120 35 0 27 1 0 1 1 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpqe 32 89 0 89 1 1 0 1 0 8 0 tcpcb 544 38 0 34 1 0 1 1 0 8 0 inpcb 296 137 0 130 2 0 2 2 0 8 1 nd6 48 14 0 9 1 0 1 1 0 8 0 pfrktable 1344 14 0 4 1 0 1 1 0 8 0 pftag 88 2 0 0 1 0 1 1 0 8 0 pfrule 1360 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 256 261 0 88 13 0 13 13 0 8 0 art_table 32 262 0 88 2 0 2 2 0 8 0 art_node 16 62 0 23 1 0 1 1 0 8 0 semupl 112 2 0 2 1 0 1 1 0 8 1 semapl 112 4 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 1484 0 88 88 0 88 88 0 8 0 ffsino 240 1484 0 88 83 0 83 83 0 8 0 nchpl 144 1770 0 167 60 0 60 60 0 8 0 uvmvnodes 72 1561 0 0 29 0 29 29 0 8 0 vnodes 208 1561 0 0 83 0 83 83 0 8 0 namei 1024 4425 0 4425 1 0 1 1 0 8 1 pfiaddrpl 120 8 0 0 1 0 1 1 0 8 0 scxspl 192 5151 0 5151 1 0 1 1 0 8 1 plimitpl 152 16 0 9 1 0 1 1 0 8 0 sigapl 424 267 0 239 4 0 4 4 0 8 0 futexpl 56 1203 0 1203 1 0 1 1 0 8 1 knotepl 112 63 0 44 1 0 1 1 0 8 0 kqueuepl 144 8 0 6 1 0 1 1 0 8 0 pipepl 272 82 0 72 1 0 1 1 0 8 0 fdescpl 432 253 0 239 2 0 2 2 0 8 0 filepl 120 1349 0 1254 4 0 4 4 0 8 1 lockfpl 104 12 0 11 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 50 0 43 1 0 1 1 0 8 0 zombiepl 144 239 0 239 1 0 1 1 0 8 1 processpl 920 267 0 239 4 0 4 4 0 8 0 procpl 624 334 0 298 4 0 4 4 0 8 0 sockpl 400 193 0 176 3 0 3 3 0 8 1 mcl64k 65536 4 0 4 1 0 1 1 0 8 1 mcl12k 12288 3 0 3 1 0 1 1 0 8 1 mcl9k 9216 1 0 1 1 0 1 1 0 8 1 mcl8k 8192 4 0 4 1 0 1 1 0 8 1 mcl4k 4096 14 0 14 2 1 1 1 0 8 1 mcl2k2 2112 1 0 1 1 0 1 1 0 8 1 mcl2k 2048 78306 0 78256 16 2 14 14 0 8 7 mtagpl 96 17 0 2 2 1 1 1 0 8 0 mbufpl 256 124488 0 124266 20 5 15 15 0 8 1 bufpl 280 3390 0 125 234 0 234 234 0 8 0 anonpl 16 39645 0 24185 65 2 63 63 0 107 0 amapchunkpl 152 1261 0 1133 8 0 8 8 0 158 2 amappl16 192 1176 0 301 44 0 44 44 0 8 0 amappl15 184 10 0 7 1 0 1 1 0 8 0 amappl14 176 27 0 22 1 0 1 1 0 8 0 amappl13 168 26 0 23 1 0 1 1 0 8 0 amappl12 160 6 0 4 1 0 1 1 0 8 0 amappl11 152 45 0 36 1 0 1 1 0 8 0 amappl10 144 14 0 10 1 0 1 1 0 8 0 amappl9 136 412 0 408 1 0 1 1 0 8 0 amappl8 128 331 0 294 2 0 2 2 0 8 0 amappl7 120 106 0 94 1 0 1 1 0 8 0 amappl6 112 29 0 19 1 0 1 1 0 8 0 amappl5 104 206 0 195 1 0 1 1 0 8 0 amappl4 96 421 0 392 1 0 1 1 0 8 0 amappl3 88 105 0 100 1 0 1 1 0 8 0 amappl2 80 1161 0 1095 3 1 2 2 0 8 0 amappl1 72 14531 0 14124 24 10 14 17 0 8 5 amappl 80 552 0 513 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 3 0 0 1 0 1 1 0 8 0 uaddrrnd 24 253 0 239 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 253 0 239 1 0 1 1 0 8 0 vmmpekpl 168 5870 0 5841 2 0 2 2 0 8 0 vmmpepl 168 37791 0 35843 122 11 111 111 0 357 26 vmsppl 272 252 0 239 2 0 2 2 0 8 1 pdppl 4096 512 0 478 6 0 6 6 0 8 1 pvpl 32 135544 0 117125 153 0 153 153 0 265 3 pmappl 200 252 0 239 1 0 1 1 0 8 0 extentpl 40 53 0 36 1 0 1 1 0 8 0 phpool 112 249 0 10 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(ffffffff8241bf9c) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd806994b800,184,33c,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(fffffd805da6e008,9,fffffd806994b700,0,0,ffff80001d7174f0) at tcp_usrreq+0xa54 sosend(fffffd805da6e008,0,ffff80001d6c9e48,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:555 dofilewritev(ffff80001d7174f0,4,ffff80001d6c9e48,0,ffff80001d6c9f30) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d7174f0,ffff80001d6c9ee0,ffff80001d6c9f30) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d6c9fb0) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7fffff4c10, 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(ffffffff8241bf9c) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd806994b800,184,33c,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(fffffd805da6e008,9,fffffd806994b700,0,0,ffff80001d7174f0) at tcp_usrreq+0xa54 sosend(fffffd805da6e008,0,ffff80001d6c9e48,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:555 dofilewritev(ffff80001d7174f0,4,ffff80001d6c9e48,0,ffff80001d6c9f30) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d7174f0,ffff80001d6c9ee0,ffff80001d6c9f30) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d6c9fb0) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7fffff4c10, count: -10