panic: tcp_output Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND * 65201 82323 0 0x2 0 0 syz-executor1542169591 db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff8257b2ef) at panic+0x177 sys/kern/subr_prf.c:198 tcp_output(ffff800000bcec00) at tcp_output+0x2cd2 sys/netinet/tcp_output.c:727 tcp_send(fffffd806d734d70,fffffd807f00b200,0,fffffd806d72e500) at tcp_send+0xc4 sys/netinet/tcp_usrreq.c:953 sosend(fffffd806d734d70,0,ffff8000212c8a70,0,fffffd806d72e500,4) at sosend+0x62a pru_send sys/sys/protosw.h:331 [inline] sosend(fffffd806d734d70,0,ffff8000212c8a70,0,fffffd806d72e500,4) at sosend+0x62a sys/kern/uipc_socket.c:646 sendit(ffff800021233508,6,ffff8000212c8bf0,4,ffff8000212c8ce0) at sendit+0x65d sys/kern/uipc_syscalls.c:694 sys_sendmsg(ffff800021233508,ffff8000212c8c98,ffff8000212c8ce0) at sys_sendmsg+0x198 sys/kern/uipc_syscalls.c:601 syscall(ffff8000212c8d60) at syscall+0x4c3 mi_syscall sys/sys/syscall_mi.h:101 [inline] syscall(ffff8000212c8d60) at syscall+0x4c3 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffde5f0, 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{0}> ddb{0}> set $lines = 0 ddb{0}> set $maxwidth = 0 ddb{0}> show panic *cpu0: tcp_output ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff8257b2ef) at panic+0x177 sys/kern/subr_prf.c:198 tcp_output(ffff800000bcec00) at tcp_output+0x2cd2 sys/netinet/tcp_output.c:727 tcp_send(fffffd806d734d70,fffffd807f00b200,0,fffffd806d72e500) at tcp_send+0xc4 sys/netinet/tcp_usrreq.c:953 sosend(fffffd806d734d70,0,ffff8000212c8a70,0,fffffd806d72e500,4) at sosend+0x62a pru_send sys/sys/protosw.h:331 [inline] sosend(fffffd806d734d70,0,ffff8000212c8a70,0,fffffd806d72e500,4) at sosend+0x62a sys/kern/uipc_socket.c:646 sendit(ffff800021233508,6,ffff8000212c8bf0,4,ffff8000212c8ce0) at sendit+0x65d sys/kern/uipc_syscalls.c:694 sys_sendmsg(ffff800021233508,ffff8000212c8c98,ffff8000212c8ce0) at sys_sendmsg+0x198 sys/kern/uipc_syscalls.c:601 syscall(ffff8000212c8d60) at syscall+0x4c3 mi_syscall sys/sys/syscall_mi.h:101 [inline] syscall(ffff8000212c8d60) at syscall+0x4c3 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffde5f0, count: -9 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff8000212c86d0 rbx 0xffffffff829a1b8f cpu_info_full_primary+0x2b8f rdx 0x3fd rcx 0 rax 0x12 r8 0x101010101010101 r9 0x8080808080808080 r10 0xd13ca4fbc730977f r11 0xd30dd340996230f2 r12 0xffffffff829a1990 cpu_info_full_primary+0x2990 r13 0 r14 0 r15 0x1 rip 0xffffffff81a16d08 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000212c86c0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor1542169591) pid=65201 stat=onproc flags process=2 proc=0 pri=51, usrpri=51, nice=20 forw=0xffffffffffffffff, list=0xffff800021233a48,0xffffffff82af9b68 process=0xffff800021298860 user=0xffff8000212c3000, vmspace=0xfffffd8008752730 estcpu=1, cpticks=1, pctcpu=0.0 user=0, sys=0, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND *82323 65201 54418 0 7 0x2 syz-executor1542169591 54418 435044 92984 0 3 0x10008a sigsusp ksh 92984 32299 18790 0 3 0x9a kqread sshd 82512 30056 1 0 3 0x100083 ttyin getty 18790 349399 1 0 3 0x88 kqread sshd 23823 510811 24200 73 3 0x1100090 kqread syslogd 24200 48907 1 0 3 0x100082 netio syslogd 13912 178941 1 0 3 0x100080 kqread resolvd 75816 384 88708 77 3 0x100092 kqread dhcpleased 79712 111377 88708 77 3 0x100092 kqread dhcpleased 88708 333291 1 0 3 0x80 kqread dhcpleased 37236 513596 0 0 3 0x14200 bored smr 77458 356678 0 0 3 0x14200 pgzero zerothread 6802 269262 0 0 3 0x14200 aiodoned aiodoned 33728 309107 0 0 3 0x14200 syncer update 99364 154418 0 0 3 0x14200 cleaner cleaner 11263 49198 0 0 3 0x14200 reaper reaper 87328 90134 0 0 3 0x14200 pgdaemon pagedaemon 98395 482150 0 0 3 0x14200 bored viomb 23352 489136 0 0 3 0x40014200 acpi0 acpi0 78048 186073 0 0 7 0x40014200 idle1 63030 323640 0 0 3 0x14200 bored softnet 27988 267343 0 0 3 0x14200 bored softnet 24755 30121 0 0 3 0x14200 bored softnet 70835 215993 0 0 3 0x14200 bored softnet 17903 111500 0 0 3 0x14200 bored systqmp 17400 166023 0 0 3 0x14200 bored systq 71996 79124 0 0 3 0x40014200 bored softclock 77729 281554 0 0 3 0x40014200 idle0 1 404537 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 82323 (syz-executor1542169591) thread 0xffff800021233508 (65201) exclusive rwlock netlock r = 0 (0xffffffff8291ebe0) #0 witness_lock+0x44d #1 sosend+0x500 sys/kern/uipc_socket.c:632 #2 sendit+0x65d sys/kern/uipc_syscalls.c:694 #3 sys_sendmsg+0x198 sys/kern/uipc_syscalls.c:601 #4 syscall+0x4c3 mi_syscall sys/sys/syscall_mi.h:101 [inline] #4 syscall+0x4c3 sys/arch/amd64/amd64/trap.c:585 #5 Xsyscall+0x128 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10149 6388K 6419K 78643K 11239 0 pcb 13 8K 8K 78643K 13 0 rtable 58 1K 2K 78643K 103 0 ifaddr 25 7K 7K 78643K 25 0 counters 40 33K 33K 78643K 40 0 ioctlops 0 0K 2K 78643K 25 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1166 73K 73K 78643K 1179 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 1K 1K 78643K 2 0 sem 2 0K 0K 78643K 2 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 1 0K 0K 78643K 1 0 proc 55 78K 79K 78643K 226 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 in_multi 11 0K 0K 78643K 11 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 25 122K 122K 78643K 25 0 exec 0 0K 2K 78643K 390 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 54 3K 4K 78643K 1421 0 UVM aobj 3 2K 2K 78643K 3 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 NDP 3 0K 0K 78643K 3 0 temp 18 4709K 4773K 78643K 2251 0 kqueue 11 16K 18K 78643K 24 0 SYN cache 2 16K 16K 78643K 2 0 ddb{0}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle plcache 128 22 0 0 1 0 1 1 0 8 0 rtpcb 120 17 0 14 1 0 1 1 0 8 0 rtentry 112 23 0 1 1 0 1 1 0 8 0 unpcb 144 33 0 20 1 0 1 1 0 8 0 syncache 296 5 0 5 2 1 1 1 0 8 1 tcpcb 768 9 0 5 1 0 1 1 0 8 0 arp 120 2 0 0 1 0 1 1 0 8 0 inpcb 368 28 0 19 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 97 0 0 7 0 7 7 0 8 0 art_table 32 98 0 0 1 0 1 1 0 8 0 art_node 16 22 0 2 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1415 0 38 87 0 87 87 0 8 0 ffsino 272 1415 0 38 92 0 92 92 0 8 0 nchpl 144 1600 0 46 58 0 58 58 0 8 0 uvmvnodes 80 1424 0 0 30 0 30 30 0 8 0 vnodes 216 1424 0 0 80 0 80 80 0 8 0 namei 1024 4094 0 4094 2 1 1 1 0 8 1 percpumem 16 32 0 0 1 0 1 1 0 8 0 kstatmem 264 6 0 0 1 0 1 1 0 8 0 scxspl 216 3972 0 3967 9 1 8 8 0 8 7 plimitpl 152 15 0 9 1 0 1 1 0 8 0 sigapl 424 294 0 264 4 0 4 4 0 8 0 knotepl 120 43 0 0 2 0 2 2 0 8 0 kqueuepl 216 20 0 13 1 0 1 1 0 8 0 pipepl 320 79 0 76 2 1 1 1 0 8 0 fdescpl 496 277 0 264 3 1 2 3 0 8 0 filepl 152 1047 0 990 3 0 3 3 0 8 0 lockfpl 104 6 0 4 1 0 1 1 0 8 0 lockfspl 48 4 0 2 1 0 1 1 0 8 0 sessionpl 144 17 0 9 1 0 1 1 0 8 0 pgrppl 48 17 0 9 1 0 1 1 0 8 0 ucredpl 104 64 0 54 1 0 1 1 0 8 0 zombiepl 144 264 0 264 2 1 1 1 0 8 1 processpl 1064 294 0 264 3 0 3 3 0 8 0 procpl 672 294 0 264 3 0 3 3 0 8 0 sockpl 488 78 0 53 4 0 4 4 0 8 0 mcl8k 8192 4 0 0 1 0 1 1 0 8 0 mcl4k 4096 3 0 0 1 0 1 1 0 8 0 mcl2k 2048 73 0 0 9 0 9 9 0 8 0 mtagpl 96 3 0 0 1 0 1 1 0 8 0 mbufpl 256 118 0 0 8 0 8 8 0 8 0 bufpl 288 1912 0 77 132 0 132 132 0 8 0 anonpl 24 35132 0 33280 15 3 12 13 0 186 0 amapchunkpl 152 2574 0 2483 5 1 4 5 0 158 0 amappl16 200 26 0 25 2 1 1 1 0 8 0 amappl15 192 61 0 56 1 0 1 1 0 8 0 amappl13 176 32 0 31 2 1 1 1 0 8 0 amappl12 168 3 0 3 2 1 1 1 0 8 1 amappl11 160 60 0 47 1 0 1 1 0 8 0 amappl9 144 473 0 471 1 0 1 1 0 8 0 amappl8 136 334 0 333 2 1 1 1 0 8 0 amappl7 128 63 0 56 1 0 1 1 0 8 0 amappl6 120 78 0 71 1 0 1 1 0 8 0 amappl5 112 81 0 73 1 0 1 1 0 8 0 amappl4 104 570 0 551 1 0 1 1 0 8 0 amappl3 96 406 0 382 1 0 1 1 0 8 0 amappl2 88 285 0 258 1 0 1 1 0 8 0 amappl1 80 8731 0 8345 11 2 9 9 0 8 0 amappl 88 1167 0 1130 2 1 1 2 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 2 0 0 1 0 1 1 0 8 0 uaddrrnd 24 278 0 265 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 278 0 265 1 0 1 1 0 8 0 vmmpekpl 168 5902 0 5884 1 0 1 1 0 8 0 vmmpepl 168 24783 0 23992 43 5 38 38 0 357 3 vmsppl 368 277 0 265 2 0 2 2 0 8 0 rwobjpl 56 8970 0 7018 29 0 29 29 0 8 0 pdppl 4096 563 0 530 51 18 33 41 0 8 0 pvpl 32 116016 0 112305 40 7 33 33 0 265 2 pmappl 248 277 0 265 2 1 1 2 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 400 0 21 11 0 11 11 0 8 0 ddb{0}> machine ddbcpu 0 Invalid cpu 0 ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff8257b2ef) at panic+0x177 sys/kern/subr_prf.c:198 tcp_output(ffff800000bcec00) at tcp_output+0x2cd2 sys/netinet/tcp_output.c:727 tcp_send(fffffd806d734d70,fffffd807f00b200,0,fffffd806d72e500) at tcp_send+0xc4 sys/netinet/tcp_usrreq.c:953 sosend(fffffd806d734d70,0,ffff8000212c8a70,0,fffffd806d72e500,4) at sosend+0x62a pru_send sys/sys/protosw.h:331 [inline] sosend(fffffd806d734d70,0,ffff8000212c8a70,0,fffffd806d72e500,4) at sosend+0x62a sys/kern/uipc_socket.c:646 sendit(ffff800021233508,6,ffff8000212c8bf0,4,ffff8000212c8ce0) at sendit+0x65d sys/kern/uipc_syscalls.c:694 sys_sendmsg(ffff800021233508,ffff8000212c8c98,ffff8000212c8ce0) at sys_sendmsg+0x198 sys/kern/uipc_syscalls.c:601 syscall(ffff8000212c8d60) at syscall+0x4c3 mi_syscall sys/sys/syscall_mi.h:101 [inline] syscall(ffff8000212c8d60) at syscall+0x4c3 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffde5f0, count: -9 ddb{0}> machine ddbcpu 1 Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp x86_ipi_db(ffff800020dd8ff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:393 x86_ipi_handler() at x86_ipi_handler+0xb7 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23 acpicpu_idle() at acpicpu_idle+0x312 sys/dev/acpi/acpicpu.c:1206 sched_idle(ffff800020dd8ff0) at sched_idle+0x417 sys/kern/kern_sched.c:175 end trace frame: 0x0, count: 10 ddb{1}> trace x86_ipi_db(ffff800020dd8ff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:393 x86_ipi_handler() at x86_ipi_handler+0xb7 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23 acpicpu_idle() at acpicpu_idle+0x312 sys/dev/acpi/acpicpu.c:1206 sched_idle(ffff800020dd8ff0) at sched_idle+0x417 sys/kern/kern_sched.c:175 end trace frame: 0x0, count: -5 ddb{1}>