panic: tcp_output Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *387476 19690 0 0 0x4000000 0 syz-executor.6 db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff82550c9e) at panic+0x161 sys/kern/subr_prf.c:198 tcp_output(ffff800000ecb5a8) at tcp_output+0x2a72 sys/netinet/tcp_output.c:727 tcp_send(fffffd807929e978,fffffd806460a800,fffffd806460ab00,fffffd806460a100) at tcp_send+0xc4 sys/netinet/tcp_usrreq.c:944 sosend(fffffd807929e978,fffffd806460ab00,ffff800023029840,0,fffffd806460a100,0) at sosend+0x62a pru_send sys/sys/protosw.h:331 [inline] sosend(fffffd807929e978,fffffd806460ab00,ffff800023029840,0,fffffd806460a100,0) at sosend+0x62a sys/kern/uipc_socket.c:646 sendit(ffff8000231e02a8,4,ffff8000230299c0,0,ffff800023029ac0) at sendit+0x64d sys/kern/uipc_syscalls.c:694 sys_sendmsg(ffff8000231e02a8,ffff800023029a68,ffff800023029ac0) at sys_sendmsg+0x198 sys/kern/uipc_syscalls.c:601 syscall(ffff800023029b30) at syscall+0x447 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x2daadf9b1c0, 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> ddb> set $lines = 0 ddb> set $maxwidth = 0 ddb> show panic *cpu0: tcp_output ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff82550c9e) at panic+0x161 sys/kern/subr_prf.c:198 tcp_output(ffff800000ecb5a8) at tcp_output+0x2a72 sys/netinet/tcp_output.c:727 tcp_send(fffffd807929e978,fffffd806460a800,fffffd806460ab00,fffffd806460a100) at tcp_send+0xc4 sys/netinet/tcp_usrreq.c:944 sosend(fffffd807929e978,fffffd806460ab00,ffff800023029840,0,fffffd806460a100,0) at sosend+0x62a pru_send sys/sys/protosw.h:331 [inline] sosend(fffffd807929e978,fffffd806460ab00,ffff800023029840,0,fffffd806460a100,0) at sosend+0x62a sys/kern/uipc_socket.c:646 sendit(ffff8000231e02a8,4,ffff8000230299c0,0,ffff800023029ac0) at sendit+0x64d sys/kern/uipc_syscalls.c:694 sys_sendmsg(ffff8000231e02a8,ffff800023029a68,ffff800023029ac0) at sys_sendmsg+0x198 sys/kern/uipc_syscalls.c:601 syscall(ffff800023029b30) at syscall+0x447 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x2daadf9b1c0, count: -9 ddb> show registers rdi 0 rsi 0x1 rbp 0xffff8000230294b0 rbx 0x68 rdx 0xffff800000d811c0 rcx 0 rax 0xffff8000231e02a8 r8 0x101010101010101 r9 0x8080808080808080 r10 0x9459ac9d0776fedc r11 0xc58f4471ac5c4b0e r12 0 r13 0 r14 0 r15 0x1 rip 0xffffffff81685218 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000230294a0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb> show proc PROC (syz-executor.6) pid=387476 stat=onproc flags process=0 proc=4000000 pri=32, usrpri=80, nice=20 forw=0xffffffffffffffff, list=0xffff8000231e0d28,0xffff800026621d00 process=0xffff800026a46820 user=0xffff800023024000, vmspace=0xfffffd805bc62998 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 51470 344317 12545 0 2 0 syz-executor.7 51470 489124 12545 0 3 0x4000080 fsleep syz-executor.7 65364 154734 85782 0 2 0 syz-executor.2 65364 509214 85782 0 3 0x4000080 fsleep syz-executor.2 19690 416253 95968 0 2 0 syz-executor.6 *19690 387476 95968 0 7 0x4000000 syz-executor.6 96839 371158 35746 0 2 0 syz-executor.3 96839 370791 35746 0 3 0x4000080 fsleep syz-executor.3 96839 371866 35746 0 3 0x4000080 fsleep syz-executor.3 80366 260733 17460 0 2 0 syz-executor.4 80366 138134 17460 0 3 0x4000080 fsleep syz-executor.4 80366 266453 17460 0 3 0x4000080 fsleep syz-executor.4 27129 223039 9226 0 2 0 syz-executor.0 27129 338583 9226 0 3 0x4000080 fsleep syz-executor.0 12545 330132 32916 0 3 0x82 nanoslp syz-executor.7 85782 245538 32916 0 3 0x82 nanoslp syz-executor.2 95968 505467 32916 0 3 0x82 nanoslp syz-executor.6 17460 278185 32916 0 3 0x82 nanoslp syz-executor.4 20351 100609 32916 0 3 0x82 nanoslp syz-executor.5 59114 230962 1 0 3 0x100083 ttyin getty 340 408568 32916 0 3 0x82 nanoslp syz-executor.1 35746 12363 32916 0 3 0x82 nanoslp syz-executor.3 97623 48337 0 0 3 0x14200 acct acct 9226 96317 32916 0 3 0x82 nanoslp syz-executor.0 22702 492505 0 0 3 0x14280 nfsidl nfsio 53222 441708 0 0 3 0x14280 nfsidl nfsio 11451 448887 0 0 3 0x14280 nfsidl nfsio 64234 41351 0 0 3 0x14280 nfsidl nfsio 66043 112671 0 0 3 0x14280 nfsidl nfsio 71212 420222 0 0 3 0x14280 nfsidl nfsio 37715 158169 0 0 3 0x14280 nfsidl nfsio 46462 315238 0 0 3 0x14280 nfsidl nfsio 53171 166351 0 0 3 0x14280 nfsidl nfsio 91565 311401 0 0 3 0x14280 nfsidl nfsio 26966 478174 0 0 3 0x14280 nfsidl nfsio 61939 8673 0 0 3 0x14280 nfsidl nfsio 78692 325729 0 0 3 0x14280 nfsidl nfsio 17398 475669 0 0 3 0x14280 nfsidl nfsio 91062 159152 0 0 3 0x14280 nfsidl nfsio 83613 34044 0 0 3 0x14280 nfsidl nfsio 22862 498002 0 0 3 0x14280 nfsidl nfsio 67481 207033 0 0 3 0x14280 nfsidl nfsio 81868 312729 0 0 3 0x14280 nfsidl nfsio 40830 56430 0 0 3 0x14280 nfsidl nfsio 13972 466637 0 0 3 0x14200 bored sosplice 32916 280734 22377 0 3 0x82 wait syz-fuzzer 32916 331237 22377 0 3 0x4000082 nanoslp syz-fuzzer 32916 418474 22377 0 3 0x4000082 thrsleep syz-fuzzer 32916 321021 22377 0 3 0x4000082 thrsleep syz-fuzzer 32916 203658 22377 0 3 0x4000082 wait syz-fuzzer 32916 242516 22377 0 3 0x4000082 wait syz-fuzzer 32916 325807 22377 0 3 0x4000082 wait syz-fuzzer 32916 489775 22377 0 3 0x4000082 wait syz-fuzzer 32916 138921 22377 0 3 0x4000082 thrsleep syz-fuzzer 32916 185094 22377 0 3 0x4000082 kqread syz-fuzzer 32916 245143 22377 0 3 0x4000082 wait syz-fuzzer 32916 433736 22377 0 3 0x4000082 wait syz-fuzzer 32916 462866 22377 0 3 0x4000082 thrsleep syz-fuzzer 32916 49792 22377 0 3 0x4000082 wait syz-fuzzer 22377 343556 25413 0 3 0x10008a sigsusp ksh 25413 189835 28476 0 3 0x9a kqread sshd 28476 204541 1 0 3 0x88 kqread sshd 87317 88218 53959 73 3 0x1100090 kqread syslogd 53959 235283 1 0 3 0x100082 netio syslogd 27591 46553 1 0 3 0x100080 kqread resolvd 72731 396725 75706 77 3 0x100092 kqread dhcpleased 6731 356771 75706 77 3 0x100092 kqread dhcpleased 75706 270533 1 0 3 0x80 kqread dhcpleased 80576 186009 0 0 3 0x14200 bored smr 87560 461972 0 0 2 0x14200 zerothread 68686 502920 0 0 3 0x14200 aiodoned aiodoned 52347 160250 0 0 3 0x14200 syncer update 59054 95794 0 0 3 0x14200 cleaner cleaner 45839 199541 0 0 3 0x14200 reaper reaper 51695 133442 0 0 3 0x14200 pgdaemon pagedaemon 57766 134404 0 0 3 0x14200 bored viomb 218 322155 0 0 3 0x40014200 acpi0 acpi0 99176 419418 0 0 3 0x14200 bored softnet 78899 190279 0 0 3 0x14200 bored softnet 74499 12591 0 0 3 0x14200 bored softnet 80570 74766 0 0 3 0x14200 bored softnet 10806 501474 0 0 3 0x14200 bored systqmp 32823 28856 0 0 3 0x14200 bored systq 26525 380133 0 0 3 0x40014200 bored softclock 26753 508846 0 0 3 0x40014200 idle0 1 120343 0 0 3 0x80082 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 10215 6437K 8087K 78643K 40029 0 pcb 13 22K 25K 78643K 2954 0 rtable 180 12K 27K 78643K 4388 0 ifaddr 93 25K 28K 78643K 1799 0 sysctl 2 0K 2K 78643K 8 0 counters 27 17K 17K 78643K 368 0 ioctlops 0 0K 4K 78643K 7549 0 iov 0 0K 28K 78643K 1927 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1587 99K 99K 78643K 12575 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 9K 78643K 121 0 VM map 2 0K 0K 78643K 2 0 sem 17 17K 33K 78643K 929 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 16 57K 73K 78643K 17572 0 sigio 0 0K 0K 78643K 1426 0 proc 65 59K 75K 78643K 3419 0 subproc 104 6K 6K 78643K 1175 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 755 0 in_multi 63 4K 6K 78643K 1430 0 ether_multi 1 0K 0K 78643K 90 0 mrt 1 0K 0K 78643K 47 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 259 1155K 1155K 78643K 259 0 exec 0 0K 2K 78643K 4929 0 pfkey data 0 0K 0K 78643K 51 0 tdb 3 0K 0K 78643K 3 0 pagedep 1 8K 8K 78643K 1 0 inodedep 1 32K 32K 78643K 1 0 newblk 1 0K 0K 78643K 1 0 VM swap 8 62K 62K 78643K 8 0 UVM amap 582 1656K 1657K 78643K 98083 0 UVM aobj 131 4K 4K 78643K 132 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 768 0 NDP 14 0K 2K 78643K 483 0 temp 135 4718K 66414K 78643K 206261 0 kqueue 12 18K 28K 78643K 1542 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 rtpcb 120 1337 0 1334 17 16 1 3 0 8 0 rtentry 112 1337 0 1267 6 2 4 4 0 8 0 unpcb 144 15227 0 15149 175 172 3 10 0 8 0 syncache 296 90 0 90 22 22 0 1 0 8 0 tcpqe 32 208 0 208 10 10 0 1 0 8 0 tcpcb 768 34018 0 33988 940 925 15 37 0 8 12 arp 88 201 0 191 1 0 1 1 0 8 0 ipq 40 26 0 26 10 10 0 1 0 8 0 ipqe 40 79 0 79 10 10 0 1 0 8 0 inpcb 336 44509 0 44496 507 498 9 23 0 8 7 ip6q 72 4 0 4 2 2 0 1 0 8 0 ip6af 40 6 0 6 2 2 0 1 0 8 0 nd6 48 313 0 298 1 0 1 1 0 8 0 pkpcb 40 116 0 116 15 15 0 1 0 8 0 kcovpl 48 90 0 82 1 0 1 1 0 8 0 ppxss 1160 199 0 198 27 26 1 1 0 8 0 pfstscr 40 88 0 79 1 0 1 1 0 8 0 pfosfp 40 6 0 4 1 0 1 1 0 8 0 pfosfpen 112 6 0 4 1 0 1 1 0 8 0 pfrktable 1344 145 0 145 5 5 0 3 0 8 0 pfanchor 1280 224 0 68 14 0 14 14 0 8 0 pftag 88 5 0 0 1 0 1 1 0 8 0 pfqueue 264 4 0 4 2 2 0 1 0 8 0 pfstitem 24 14 0 4 1 0 1 1 0 8 0 pfstkey 120 158 0 152 1 0 1 1 0 8 0 pfstate 336 82 0 77 1 0 1 1 0 8 0 pfrule 1360 1051 0 1051 7 7 0 7 0 8 0 rttmr 136 9 0 9 3 3 0 1 0 8 0 art_heap8 4096 17 0 15 13 11 2 3 0 8 0 art_heap4 256 6131 0 5791 73 50 23 31 0 8 0 art_table 32 6148 0 5806 6 2 4 4 0 8 0 art_node 16 1320 0 1260 1 0 1 1 0 8 0 sysvmsgpl 40 18 0 11 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 911 0 896 1 0 1 1 0 8 0 shmpl 112 129 0 1 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 25481 0 23979 95 0 95 95 0 8 0 ffsino 240 25481 0 23979 89 0 89 89 0 8 0 nchpl 144 48103 0 46469 63 0 63 63 0 8 0 rtmask 32 8 0 8 3 3 0 1 0 8 0 uvmvnodes 80 5926 0 0 121 0 121 121 0 8 0 vnodes 216 5926 0 0 330 0 330 330 0 8 0 namei 1024 180622 0 180622 7 6 1 2 0 8 1 vcpupl 2048 146 0 0 19 0 19 19 0 8 0 vmpool 536 165 0 19 12 2 10 10 0 8 0 pfiaddrpl 120 107 0 107 2 2 0 2 0 8 0 kstatmem 264 540 0 512 3 0 3 3 0 8 0 scsiplug 72 19 0 19 4 4 0 1 0 8 0 scxspl 216 143024 0 143024 31 30 1 8 0 8 1 plimitpl 152 2269 0 2255 1 0 1 1 0 8 0 sigapl 424 17743 0 17676 10 2 8 8 0 8 0 futexpl 64 193493 0 193486 3 2 1 1 0 8 0 knotepl 120 270520 0 270440 84 77 7 16 0 8 3 kqueuepl 184 3733 0 3725 46 45 1 4 0 8 0 pipepl 288 4901 0 4873 96 91 5 8 0 8 2 fdescpl 432 17683 0 17656 4 0 4 4 0 8 0 filepl 120 154733 0 154427 232 220 12 19 0 8 2 lockfpl 104 4397 0 4395 12 11 1 4 0 8 0 lockfspl 48 1270 0 1268 1 0 1 1 0 8 0 sessionpl 144 112 0 96 1 0 1 1 0 8 0 pgrppl 48 311 0 295 1 0 1 1 0 8 0 ucredpl 104 15877 0 15867 1 0 1 1 0 8 0 zombiepl 144 17678 0 17676 6 5 1 1 0 8 0 processpl 1000 17743 0 17676 11 2 9 9 0 8 0 procpl 672 46033 0 45945 50 42 8 9 0 8 0 sosppl 168 175 0 175 28 28 0 1 0 8 0 sockpl 456 61210 0 61113 1395 1382 13 46 0 8 0 mcl64k 65536 591 0 588 33 32 1 2 0 8 0 mcl16k 16384 182 0 182 45 45 0 1 0 8 0 mcl12k 12288 537 0 537 39 38 1 1 0 8 1 mcl9k 9216 285 0 285 41 41 0 1 0 8 0 mcl8k 8192 997 0 997 35 34 1 1 0 8 1 mcl4k 4096 2010 0 2010 18 17 1 1 0 8 1 mcl2k2 2112 170 0 170 48 48 0 1 0 8 0 mcl2k 2048 105722 0 105547 47 24 23 24 0 8 0 mtagpl 96 2892 0 2427 31 16 15 16 0 8 0 mbufpl 256 325865 0 325197 179 128 51 53 0 8 0 bufpl 288 33884 0 27480 458 0 458 458 0 8 0 anonpl 24 3448821 0 3427756 395 249 146 207 0 188 5 amapchunkpl 152 302398 0 301398 185 145 40 66 0 158 0 amappl16 200 50792 0 50087 218 177 41 50 0 8 3 amappl15 192 1642 0 1636 1 0 1 1 0 8 0 amappl14 184 1301 0 1295 1 0 1 1 0 8 0 amappl13 176 2786 0 2782 1 0 1 1 0 8 0 amappl12 168 2013 0 2007 1 0 1 1 0 8 0 amappl11 160 2075 0 2058 1 0 1 1 0 8 0 amappl10 152 3242 0 3240 1 0 1 1 0 8 0 amappl9 144 3577 0 3570 1 0 1 1 0 8 0 amappl8 136 3990 0 3895 4 0 4 4 0 8 0 amappl7 128 2303 0 2275 1 0 1 1 0 8 0 amappl6 120 3852 0 3828 2 1 1 2 0 8 0 amappl5 112 16774 0 16760 1 0 1 1 0 8 0 amappl4 104 6017 0 5981 11 10 1 2 0 8 0 amappl3 96 53782 0 53717 2 0 2 2 0 8 0 amappl2 88 4255 0 4221 2 0 2 2 0 8 0 amappl1 80 432240 0 431571 19 4 15 19 0 8 0 amappl 88 95656 0 95389 8 1 7 7 0 92 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma1024 1024 1 0 0 1 0 1 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 72 131 0 1 3 0 3 3 0 8 0 uaddrrnd 24 17848 0 17675 2 0 2 2 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 17848 0 17675 2 0 2 2 0 8 0 vmmpekpl 168 132599 0 132514 5 0 5 5 0 8 0 vmmpepl 168 1741333 0 1738422 419 273 146 160 0 357 5 vmsppl 272 17847 0 17675 13 1 12 12 0 8 0 rwobjpl 24 418113 0 410190 50 0 50 50 0 8 0 pdppl 4096 35702 0 35496 1147 937 210 210 0 8 4 pvpl 32 6617107 0 6596914 500 304 196 313 0 265 0 pmappl 216 17847 0 17675 11 1 10 10 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 2888 0 1883 29 0 29 29 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:437 panic(ffffffff82550c9e) at panic+0x161 sys/kern/subr_prf.c:198 tcp_output(ffff800000ecb5a8) at tcp_output+0x2a72 sys/netinet/tcp_output.c:727 tcp_send(fffffd807929e978,fffffd806460a800,fffffd806460ab00,fffffd806460a100) at tcp_send+0xc4 sys/netinet/tcp_usrreq.c:944 sosend(fffffd807929e978,fffffd806460ab00,ffff800023029840,0,fffffd806460a100,0) at sosend+0x62a pru_send sys/sys/protosw.h:331 [inline] sosend(fffffd807929e978,fffffd806460ab00,ffff800023029840,0,fffffd806460a100,0) at sosend+0x62a sys/kern/uipc_socket.c:646 sendit(ffff8000231e02a8,4,ffff8000230299c0,0,ffff800023029ac0) at sendit+0x64d sys/kern/uipc_syscalls.c:694 sys_sendmsg(ffff8000231e02a8,ffff800023029a68,ffff800023029ac0) at sys_sendmsg+0x198 sys/kern/uipc_syscalls.c:601 syscall(ffff800023029b30) at syscall+0x447 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x2daadf9b1c0, count: -9 ddb> machine ddbcpu 1 No such command ddb> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff82550c9e) at panic+0x161 sys/kern/subr_prf.c:198 tcp_output(ffff800000ecb5a8) at tcp_output+0x2a72 sys/netinet/tcp_output.c:727 tcp_send(fffffd807929e978,fffffd806460a800,fffffd806460ab00,fffffd806460a100) at tcp_send+0xc4 sys/netinet/tcp_usrreq.c:944 sosend(fffffd807929e978,fffffd806460ab00,ffff800023029840,0,fffffd806460a100,0) at sosend+0x62a pru_send sys/sys/protosw.h:331 [inline] sosend(fffffd807929e978,fffffd806460ab00,ffff800023029840,0,fffffd806460a100,0) at sosend+0x62a sys/kern/uipc_socket.c:646 sendit(ffff8000231e02a8,4,ffff8000230299c0,0,ffff800023029ac0) at sendit+0x64d sys/kern/uipc_syscalls.c:694 sys_sendmsg(ffff8000231e02a8,ffff800023029a68,ffff800023029ac0) at sys_sendmsg+0x198 sys/kern/uipc_syscalls.c:601 syscall(ffff800023029b30) at syscall+0x447 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x2daadf9b1c0, count: -9