panic(ffffffff82208062) at panic+0x15c sys/kern/subr_prf.c:207 tcp_output(ffff800000a0b320) at tcp_output+0x2c4b tcp_setpersist sys/netinet/tcp_output.c:1130 [inline] tcp_output(ffff800000a0b320) at tcp_output+0x2c4b sys/netinet/tcp_output.c:333 tcp_usrreq(fffffd806eb77af8,9,fffffd80677e7f00,0,0,ffff800020adeeb0) at tcp_usrreq+0xa55 sosend(fffffd806eb77af8,0,ffff800020acfbf8,0,0,80) at sosend+0x671 sys/kern/uipc_socket.c:549 dofilewritev(ffff800020adeeb0,4,ffff800020acfbf8,0,ffff800020acfce0) at dofilewritev+0x1b6 sys/kern/sys_generic.c:365 sys_write(ffff800020adeeb0,ffff800020acfc90,ffff800020acfce0) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff800020acfd60) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800020acfd60) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffb9100, count: 6 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{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic tcp_output: template len != hdrlen - optlen ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff82208062) at panic+0x15c sys/kern/subr_prf.c:207 tcp_output(ffff800000a0b320) at tcp_output+0x2c4b tcp_setpersist sys/netinet/tcp_output.c:1130 [inline] tcp_output(ffff800000a0b320) at tcp_output+0x2c4b sys/netinet/tcp_output.c:333 tcp_usrreq(fffffd806eb77af8,9,fffffd80677e7f00,0,0,ffff800020adeeb0) at tcp_usrreq+0xa55 sosend(fffffd806eb77af8,0,ffff800020acfbf8,0,0,80) at sosend+0x671 sys/kern/uipc_socket.c:549 dofilewritev(ffff800020adeeb0,4,ffff800020acfbf8,0,ffff800020acfce0) at dofilewritev+0x1b6 sys/kern/sys_generic.c:365 sys_write(ffff800020adeeb0,ffff800020acfc90,ffff800020acfce0) at sys_write+0x83 sys/kern/sys_generic.c:285 syscall(ffff800020acfd60) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800020acfd60) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffb9100, count: -9 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff800020acf760 rbx 0xffff800020acf810 rdx 0xffff800020adeeb0 rcx 0 rax 0 r8 0xffffffff81963d9f kprintf+0x16f r9 0x1 r10 0x25 r11 0x8bb633487d12f418 r12 0x3000000008 r13 0xffff800020acf770 r14 0x100 r15 0x1 rip 0xffffffff81d1f4b8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020acf750 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (sshd) pid=220658 stat=onproc flags process=12 proc=0 pri=50, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff800020adec40,0xffff800020adf610 process=0xffff800020ac83f0 user=0xffff800020aca000, vmspace=0xfffffd806e9a7458 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 29758 351253 20671 0 2 0 syz-executor.0 29758 352411 20671 0 2 0x4000000 syz-executor.0 24212 236353 0 0 3 0x14200 bored sosplice 18833 304902 86843 0 7 0x2 syz-executor.1 20671 87951 86843 0 3 0x82 nanosleep syz-executor.0 86843 486250 89591 0 3 0x82 thrsleep syz-fuzzer 86843 314715 89591 0 3 0x4000082 nanosleep syz-fuzzer 86843 2719 89591 0 3 0x4000082 thrsleep syz-fuzzer 86843 213673 89591 0 3 0x4000082 thrsleep syz-fuzzer 86843 213559 89591 0 3 0x4000082 thrsleep syz-fuzzer 86843 392810 89591 0 3 0x4000082 thrsleep syz-fuzzer 86843 178336 89591 0 3 0x4000082 thrsleep syz-fuzzer 86843 269608 89591 0 3 0x4000082 thrsleep syz-fuzzer 86843 507214 89591 0 3 0x4000082 thrsleep syz-fuzzer 86843 381852 89591 0 2 0x4000002 syz-fuzzer 89591 471257 45559 0 3 0x10008a pause ksh *45559 220658 71795 0 7 0x12 sshd 35039 192667 1 0 3 0x100083 ttyin getty 71795 166832 1 0 3 0x80 select sshd 93638 401193 22275 74 3 0x100092 bpf pflogd 22275 237419 1 0 3 0x80 netio pflogd 19663 364192 26383 73 3 0x100090 kqread syslogd 26383 90620 1 0 3 0x100082 netio syslogd 25857 161265 1 77 3 0x100090 poll dhclient 84316 14842 1 0 3 0x80 poll dhclient 76301 90053 0 0 3 0x14200 bored smr 84638 338744 0 0 2 0x14200 zerothread 93548 414608 0 0 3 0x14200 aiodoned aiodoned 80658 79110 0 0 3 0x14200 syncer update 92752 303542 0 0 3 0x14200 cleaner cleaner 53075 141878 0 0 3 0x14200 reaper reaper 11334 497085 0 0 3 0x14200 pgdaemon pagedaemon 28074 92594 0 0 3 0x14200 bored crynlk 50707 146112 0 0 3 0x14200 bored crypto 13349 87590 0 0 3 0x40014200 acpi0 acpi0 77017 144358 0 0 3 0x40014200 idle1 65394 216941 0 0 3 0x14200 bored softnet 73655 293621 0 0 3 0x14200 bored systqmp 68287 7430 0 0 3 0x14200 bored systq 80785 339328 0 0 3 0x40014200 bored softclock 75967 57847 0 0 3 0x40014200 idle0 1 29856 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks CPU 0: exclusive mutex &newfdp->fd_fd.fd_fplock r = 0 (0xfffffd806e903288) #0 witness_lock+0x4c5 sys/kern/subr_witness.c:1164 #1 mtx_enter_try+0x102 #2 mtx_enter+0x4b sys/kern/kern_lock.c:266 #3 fd_getfile+0x4b sys/kern/kern_descrip.c:241 #4 sys_getdents+0x66 getvnode sys/kern/vfs_syscalls.c:3201 [inline] #4 sys_getdents+0x66 sys/kern/vfs_syscalls.c:3092 #5 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #5 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #6 Xsyscall+0x128 Process 18833 (syz-executor.1) thread 0xffff800020a6d868 (304902) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82670648) #0 witness_lock+0x4c5 sys/kern/subr_witness.c:1164 #1 syscall+0x400 mi_syscall sys/sys/syscall_mi.h:93 [inline] #1 syscall+0x400 sys/arch/amd64/amd64/trap.c:570 #2 Xsyscall+0x128 Process 45559 (sshd) thread 0xffff800020adeeb0 (220658) exclusive rwlock netlock r = 0 (0xffffffff824d6d68) #0 witness_lock+0x4c5 sys/kern/subr_witness.c:1164 #1 solock+0x5a sys/kern/uipc_socket2.c:282 #2 sosend+0x559 sys/kern/uipc_socket.c:537 #3 dofilewritev+0x1b6 sys/kern/sys_generic.c:365 #4 sys_write+0x83 sys/kern/sys_generic.c:285 #5 syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] #5 syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 #6 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9501 6541K 6937K 78643K 10802 0 pcb 13 8K 8K 78643K 45 0 rtable 89 2K 3K 78643K 260 0 ifaddr 57 12K 13K 78643K 86 0 counters 43 33K 34K 78643K 51 0 ioctlops 0 0K 4K 78643K 1481 0 iov 0 0K 16K 78643K 14 0 mount 1 1K 1K 78643K 1 0 vnodes 1223 77K 77K 78643K 1293 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 1K 1K 78643K 2 0 sem 12 0K 0K 78643K 22 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 196K 290K 78643K 12766 0 file desc 5 13K 25K 78643K 149 0 sigio 0 0K 0K 78643K 5 0 proc 60 63K 95K 78643K 447 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 129 0 in_multi 39 2K 2K 78643K 68 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 55 254K 254K 78643K 55 0 exec 0 0K 1K 78643K 230 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 93 37K 37K 78643K 1404 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 1K 78643K 38 0 NDP 8 0K 0K 78643K 17 0 temp 78 3040K 3104K 78643K 3729 0 kqueue 3 4K 8K 78643K 8 0 SYN cache 2 16K 16K 78643K 2 0 ddb{1}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 7 0 0 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 23 0 21 1 0 1 1 0 8 0 rtentry 112 55 0 19 2 0 2 2 0 8 0 unpcb 120 83 0 73 1 0 1 1 0 8 0 syncache 264 7 0 7 2 1 1 1 0 8 1 tcpqe 32 67 0 67 1 1 0 1 0 8 0 tcpcb 544 212 0 208 2 0 2 2 0 8 1 inpcb 280 451 0 444 2 0 2 2 0 8 1 rttmr 72 1 0 1 1 0 1 1 0 8 1 nd6 48 7 0 3 1 0 1 1 0 8 0 pffrag 232 2 0 2 1 0 1 1 0 482 1 pffrnode 88 2 0 2 1 0 1 1 0 8 1 pffrent 40 90 0 90 1 0 1 1 0 8 1 pfosfp 40 846 0 423 5 0 5 5 0 8 0 pfosfpen 112 1428 0 714 21 0 21 21 0 8 0 pfstitem 24 31 0 1 1 0 1 1 0 8 0 pfstkey 112 31 0 1 1 0 1 1 0 8 0 pfstate 328 31 0 0 3 0 3 3 0 8 0 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 285 0 112 13 0 13 13 0 8 1 art_table 32 286 0 112 2 0 2 2 0 8 0 art_node 16 54 0 23 1 0 1 1 0 8 0 semupl 112 2 0 2 1 0 1 1 0 8 1 semapl 112 20 0 10 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 dino1pl 128 1599 0 189 46 0 46 46 0 8 0 ffsino 272 1599 0 189 95 0 95 95 0 8 0 nchpl 144 1985 0 380 61 0 61 61 0 8 0 uvmvnodes 72 1690 0 0 31 0 31 31 0 8 0 vnodes 208 1690 0 0 89 0 89 89 0 8 0 namei 1024 5215 0 5215 1 0 1 1 0 8 1 percpumem 16 36 0 4 1 0 1 1 0 8 0 vcpupl 1984 2 0 0 1 0 1 1 0 8 0 vmpool 560 4 0 2 1 0 1 1 0 8 0 scxspl 192 5946 0 5946 6 1 5 5 0 8 5 plimitpl 152 27 0 19 1 0 1 1 0 8 0 sigapl 424 365 0 333 4 0 4 4 0 8 0 futexpl 56 2264 0 2264 1 0 1 1 0 8 1 knotepl 112 59 0 40 1 0 1 1 0 8 0 kqueuepl 144 26 0 24 1 0 1 1 0 8 0 pipelkpl 48 88 0 78 1 0 1 1 0 8 0 pipepl 120 176 0 157 1 0 1 1 0 8 0 fdescpl 496 349 0 333 3 0 3 3 0 8 0 filepl 152 2074 0 1973 5 0 5 5 0 8 1 lockfpl 104 29 0 28 1 0 1 1 0 8 0 lockfspl 48 11 0 10 1 0 1 1 0 8 0 sessionpl 112 18 0 7 1 0 1 1 0 8 0 pgrppl 48 20 0 9 1 0 1 1 0 8 0 ucredpl 96 157 0 148 1 0 1 1 0 8 0 zombiepl 144 333 0 333 1 0 1 1 0 8 1 processpl 984 365 0 333 5 0 5 5 0 8 0 procpl 624 654 0 612 4 0 4 4 0 8 0 sosppl 128 4 0 4 1 0 1 1 0 8 1 sockpl 400 559 0 540 5 0 5 5 0 8 3 mcl64k 65536 4 0 0 1 0 1 1 0 8 0 mcl12k 12288 2 0 0 1 0 1 1 0 8 0 mcl9k 9216 2 0 0 1 0 1 1 0 8 0 mcl8k 8192 1 0 0 1 0 1 1 0 8 0 mcl4k 4096 8 0 0 1 0 1 1 0 8 0 mcl2k2 2112 1 0 0 1 0 1 1 0 8 0 mcl2k 2048 132 0 0 16 0 16 16 0 8 0 mtagpl 80 10 0 0 1 0 1 1 0 8 0 mbufpl 256 278 0 0 17 0 17 17 0 8 0 bufpl 280 4227 0 179 290 0 290 290 0 8 0 anonpl 16 46291 0 32737 68 1 67 67 0 124 12 amapchunkpl 152 1864 0 1734 8 0 8 8 0 158 1 amappl16 192 1528 0 802 46 1 45 46 0 8 8 amappl15 184 4 0 3 1 0 1 1 0 8 0 amappl14 176 2 0 2 2 2 0 1 0 8 0 amappl13 168 29 0 27 1 0 1 1 0 8 0 amappl12 160 13 0 12 2 1 1 1 0 8 0 amappl11 152 134 0 115 1 0 1 1 0 8 0 amappl10 144 78 0 69 1 0 1 1 0 8 0 amappl9 136 388 0 385 1 0 1 1 0 8 0 amappl8 128 299 0 287 1 0 1 1 0 8 0 amappl7 120 174 0 161 1 0 1 1 0 8 0 amappl6 112 81 0 77 1 0 1 1 0 8 0 amappl5 104 249 0 232 1 0 1 1 0 8 0 amappl4 96 505 0 472 2 1 1 2 0 8 0 amappl3 88 111 0 103 1 0 1 1 0 8 0 amappl2 80 1875 0 1805 3 0 3 3 0 8 0 amappl1 72 17880 0 17446 25 11 14 20 0 8 4 amappl 80 908 0 865 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 24 353 0 335 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 353 0 335 1 0 1 1 0 8 0 vmmpekpl 168 6626 0 6597 2 0 2 2 0 8 0 vmmpepl 168 49249 0 47398 106 5 101 101 0 357 18 vmsppl 368 352 0 335 2 0 2 2 0 8 0 pdppl 4096 714 0 672 6 0 6 6 0 8 0 pvpl 32 158894 0 142207 163 0 163 163 0 265 28 pmappl 232 352 0 335 2 0 2 2 0 8 1 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 172 0 3 5 0 5 5 0 8 0