panic: m_copym0: m == NULL and not COPYALL Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *249356 18667 0 0x12 0 0 sshd db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff82427d43) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd80537fed00,16c,574,2) at m_copym+0x589 sys/kern/uipc_mbuf.c:664 tcp_output(ffff800000ac2aa0) at tcp_output+0x154d sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd805da6f7d8,9,fffffd80537fec00,0,0,ffff80001d71c4f0) at tcp_usrreq+0xa54 sosend(fffffd805da6f7d8,0,ffff80001d6ccfd8,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:555 dofilewritev(ffff80001d71c4f0,4,ffff80001d6ccfd8,0,ffff80001d6cd0c0) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d71c4f0,ffff80001d6cd070,ffff80001d6cd0c0) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d6cd140) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7fffff6f50, 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(ffffffff82427d43) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd80537fed00,16c,574,2) at m_copym+0x589 sys/kern/uipc_mbuf.c:664 tcp_output(ffff800000ac2aa0) at tcp_output+0x154d sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd805da6f7d8,9,fffffd80537fec00,0,0,ffff80001d71c4f0) at tcp_usrreq+0xa54 sosend(fffffd805da6f7d8,0,ffff80001d6ccfd8,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:555 dofilewritev(ffff80001d71c4f0,4,ffff80001d6ccfd8,0,ffff80001d6cd0c0) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d71c4f0,ffff80001d6cd070,ffff80001d6cd0c0) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d6cd140) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7fffff6f50, count: -10 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff80001d6ccaa0 rbx 0xffff80001d6ccb50 rdx 0x2 rcx 0 rax 0x1 r8 0xffffffff81443f7f kprintf+0x15f r9 0x1 r10 0x2 r11 0x15448dc284f8fa0a r12 0x3000000008 r13 0xffff80001d6ccab0 r14 0x100 r15 0x1 rip 0xffffffff8197d558 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff80001d6cca90 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (sshd) pid=249356 stat=onproc flags process=12 proc=0 pri=24, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff80001d71ceb0,0xffff80001d71c020 process=0xffff80001d706af8 user=0xffff80001d6c8000, vmspace=0xfffffd806bc0a440 estcpu=0, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 34337 123239 33697 0 2 0 syz-executor.1 34337 76729 33697 0 3 0x4000080 msgwait syz-executor.1 33697 279554 78640 0 3 0x82 nanosleep syz-executor.1 1478 416255 78640 0 2 0x2 syz-executor.0 78640 28286 32187 0 3 0x82 thrsleep syz-fuzzer 78640 214519 32187 0 2 0x4000482 syz-fuzzer 78640 484001 32187 0 3 0x4000082 thrsleep syz-fuzzer 78640 111421 32187 0 3 0x4000082 thrsleep syz-fuzzer 78640 271110 32187 0 3 0x4000082 thrsleep syz-fuzzer 78640 427044 32187 0 2 0x4000002 syz-fuzzer 78640 432201 32187 0 3 0x4000082 thrsleep syz-fuzzer 78640 105437 32187 0 3 0x4000082 thrsleep syz-fuzzer 32187 226706 18667 0 3 0x10008a pause ksh *18667 249356 9331 0 7 0x12 sshd 99819 261239 1 0 3 0x100083 ttyin getty 9331 88281 1 0 3 0x80 select sshd 93175 137594 95567 73 3 0x100090 kqread syslogd 95567 278864 1 0 3 0x100082 netio syslogd 87257 296959 1 77 3 0x100090 poll dhclient 54375 522795 1 0 3 0x80 poll dhclient 1129 126028 0 0 3 0x14200 bored smr 30220 49566 0 0 2 0x14200 zerothread 17053 108673 0 0 3 0x14200 aiodoned aiodoned 25172 478978 0 0 3 0x14200 syncer update 95773 450571 0 0 3 0x14200 cleaner cleaner 47622 274465 0 0 3 0x14200 reaper reaper 89808 434062 0 0 3 0x14200 pgdaemon pagedaemon 47684 469583 0 0 3 0x14200 bored crynlk 50128 333681 0 0 3 0x14200 bored crypto 94944 34355 0 0 3 0x40014200 acpi0 acpi0 21797 306922 0 0 3 0x14200 bored softnet 26243 269809 0 0 3 0x14200 bored systqmp 96915 7929 0 0 3 0x14200 bored systq 34068 276153 0 0 3 0x40014200 bored softclock 40452 22230 0 0 3 0x40014200 idle0 1 284926 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 9455 6326K 6453K 78643K 10577 0 pcb 13 8K 8K 78643K 23 0 rtable 105 3K 3K 78643K 191 0 ifaddr 44 10K 10K 78643K 46 0 counters 21 16K 16K 78643K 21 0 ioctlops 0 0K 2K 78643K 19 0 iov 0 0K 12K 78643K 3 0 mount 1 1K 1K 78643K 1 0 vnodes 1220 77K 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 6 0K 1K 78643K 8 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 195K 288K 78643K 12938 0 file desc 5 13K 25K 78643K 70 0 proc 48 38K 54K 78643K 376 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 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 113 22K 38K 78643K 1008 0 UVM aobj 5 2K 2K 78643K 7 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 4 0 NDP 6 0K 0K 78643K 10 0 temp 79 3851K 3914K 78643K 1864 0 kqueue 3 4K 16K 78643K 17 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 45 0 1 2 0 2 2 0 8 0 unpcb 120 97 0 89 1 0 1 1 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpqe 32 138 0 138 2 2 0 1 0 8 0 tcpcb 544 30 0 25 1 0 1 1 0 8 0 inpcb 296 62 0 54 1 0 1 1 0 8 0 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 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 4 0 0 1 0 1 1 0 8 0 shmpl 112 4 0 2 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1464 0 65 88 0 88 88 0 8 0 ffsino 240 1464 0 65 83 0 83 83 0 8 0 nchpl 144 1768 0 164 60 0 60 60 0 8 0 uvmvnodes 72 1512 0 0 28 0 28 28 0 8 0 vnodes 208 1512 0 0 80 0 80 80 0 8 0 namei 1024 4379 0 4379 2 1 1 1 0 8 1 vmpool 528 2 0 2 1 1 0 1 0 8 0 scxspl 192 5233 0 5233 1 0 1 1 0 8 1 plimitpl 152 16 0 9 1 0 1 1 0 8 0 sigapl 424 256 0 228 4 0 4 4 0 8 0 futexpl 56 892 0 892 2 1 1 1 0 8 1 knotepl 112 75 0 56 1 0 1 1 0 8 0 kqueuepl 144 50 0 48 1 0 1 1 0 8 0 pipepl 272 70 0 60 1 0 1 1 0 8 0 fdescpl 432 242 0 228 2 0 2 2 0 8 0 filepl 120 1312 0 1216 4 0 4 4 0 8 1 lockfpl 104 7 0 6 1 0 1 1 0 8 0 lockfspl 48 4 0 3 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 79 0 72 1 0 1 1 0 8 0 zombiepl 144 228 0 228 1 0 1 1 0 8 1 processpl 928 256 0 228 4 0 4 4 0 8 0 procpl 624 315 0 279 5 1 4 4 0 8 1 sockpl 400 180 0 162 6 2 4 4 0 8 2 mcl64k 65536 515 0 515 33 0 33 33 0 8 33 mcl8k 8192 1 0 1 1 0 1 1 0 8 1 mcl4k 4096 12 0 12 2 2 0 1 0 8 0 mcl2k2 2112 1 0 1 1 0 1 1 0 8 1 mcl2k 2048 93667 0 93617 17 9 8 14 0 8 1 mtagpl 96 6 0 2 2 1 1 1 0 8 0 mbufpl 256 147746 0 147651 22 0 22 22 0 8 10 bufpl 280 3453 0 126 238 0 238 238 0 8 0 anonpl 16 43999 0 28198 81 1 80 80 0 107 16 amapchunkpl 152 1591 0 1463 21 2 19 19 0 158 13 amappl16 192 1380 0 503 55 0 55 55 0 8 11 amappl15 184 1 0 0 1 0 1 1 0 8 0 amappl14 176 26 0 22 1 0 1 1 0 8 0 amappl13 168 54 0 48 1 0 1 1 0 8 0 amappl12 160 31 0 26 1 0 1 1 0 8 0 amappl11 152 47 0 37 1 0 1 1 0 8 0 amappl10 144 31 0 25 1 0 1 1 0 8 0 amappl9 136 302 0 301 1 0 1 1 0 8 0 amappl8 128 322 0 283 2 0 2 2 0 8 0 amappl7 120 121 0 110 1 0 1 1 0 8 0 amappl6 112 27 0 20 1 0 1 1 0 8 0 amappl5 104 310 0 299 1 0 1 1 0 8 0 amappl4 96 443 0 413 1 0 1 1 0 8 0 amappl3 88 120 0 113 1 0 1 1 0 8 0 amappl2 80 1059 0 993 2 0 2 2 0 8 0 amappl1 72 14409 0 13987 23 13 10 17 0 8 0 amappl 80 543 0 504 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 6 0 2 1 0 1 1 0 8 0 uaddrrnd 24 244 0 230 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 244 0 230 1 0 1 1 0 8 0 vmmpekpl 168 5771 0 5740 2 0 2 2 0 8 0 vmmpepl 168 37502 0 35520 122 13 109 116 0 357 22 vmsppl 272 243 0 230 2 1 1 2 0 8 0 pdppl 4096 494 0 460 6 1 5 6 0 8 0 pvpl 32 139981 0 121216 189 1 188 188 0 265 36 pmappl 200 243 0 230 1 0 1 1 0 8 0 extentpl 40 53 0 36 1 0 1 1 0 8 0 phpool 112 287 0 19 8 0 8 8 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(ffffffff82427d43) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd80537fed00,16c,574,2) at m_copym+0x589 sys/kern/uipc_mbuf.c:664 tcp_output(ffff800000ac2aa0) at tcp_output+0x154d sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd805da6f7d8,9,fffffd80537fec00,0,0,ffff80001d71c4f0) at tcp_usrreq+0xa54 sosend(fffffd805da6f7d8,0,ffff80001d6ccfd8,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:555 dofilewritev(ffff80001d71c4f0,4,ffff80001d6ccfd8,0,ffff80001d6cd0c0) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d71c4f0,ffff80001d6cd070,ffff80001d6cd0c0) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d6cd140) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7fffff6f50, 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(ffffffff82427d43) at panic+0x15c sys/kern/subr_prf.c:207 m_copym(fffffd80537fed00,16c,574,2) at m_copym+0x589 sys/kern/uipc_mbuf.c:664 tcp_output(ffff800000ac2aa0) at tcp_output+0x154d sys/netinet/tcp_output.c:673 tcp_usrreq(fffffd805da6f7d8,9,fffffd80537fec00,0,0,ffff80001d71c4f0) at tcp_usrreq+0xa54 sosend(fffffd805da6f7d8,0,ffff80001d6ccfd8,0,0,80) at sosend+0x669 sys/kern/uipc_socket.c:555 dofilewritev(ffff80001d71c4f0,4,ffff80001d6ccfd8,0,ffff80001d6cd0c0) at dofilewritev+0x1ab sys/kern/sys_generic.c:365 sys_write(ffff80001d71c4f0,ffff80001d6cd070,ffff80001d6cd0c0) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff80001d6cd140) at syscall+0x507 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7fffff6f50, count: -10