panic: tcp_output Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 159413 48706 32767 0x10 0 1 syz-executor.1 *414678 48706 32767 0x10 0x4000000 0 syz-executor.1 db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff8257e05d) at panic+0x177 sys/kern/subr_prf.c:198 tcp_output(ffff800000bba900) at tcp_output+0x2cd2 sys/netinet/tcp_output.c:727 tcp_send(fffffd80671143f8,fffffd806730d500,0,fffffd807059ed00) at tcp_send+0xc4 sys/netinet/tcp_usrreq.c:944 sosend(fffffd80671143f8,0,ffff800027207e40,0,fffffd807059ed00,0) at sosend+0x62a pru_send sys/sys/protosw.h:331 [inline] sosend(fffffd80671143f8,0,ffff800027207e40,0,fffffd807059ed00,0) at sosend+0x62a sys/kern/uipc_socket.c:646 sendit(ffff800029656a80,5,ffff800027207fc0,0,ffff8000272080b0) at sendit+0x65d sys/kern/uipc_syscalls.c:694 sys_sendmsg(ffff800029656a80,ffff800027208068,ffff8000272080b0) at sys_sendmsg+0x198 sys/kern/uipc_syscalls.c:601 syscall(ffff800027208130) at syscall+0x4c3 mi_syscall sys/sys/syscall_mi.h:101 [inline] syscall(ffff800027208130) at syscall+0x4c3 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7ee878b5750, 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(ffffffff8257e05d) at panic+0x177 sys/kern/subr_prf.c:198 tcp_output(ffff800000bba900) at tcp_output+0x2cd2 sys/netinet/tcp_output.c:727 tcp_send(fffffd80671143f8,fffffd806730d500,0,fffffd807059ed00) at tcp_send+0xc4 sys/netinet/tcp_usrreq.c:944 sosend(fffffd80671143f8,0,ffff800027207e40,0,fffffd807059ed00,0) at sosend+0x62a pru_send sys/sys/protosw.h:331 [inline] sosend(fffffd80671143f8,0,ffff800027207e40,0,fffffd807059ed00,0) at sosend+0x62a sys/kern/uipc_socket.c:646 sendit(ffff800029656a80,5,ffff800027207fc0,0,ffff8000272080b0) at sendit+0x65d sys/kern/uipc_syscalls.c:694 sys_sendmsg(ffff800029656a80,ffff800027208068,ffff8000272080b0) at sys_sendmsg+0x198 sys/kern/uipc_syscalls.c:601 syscall(ffff800027208130) at syscall+0x4c3 mi_syscall sys/sys/syscall_mi.h:101 [inline] syscall(ffff800027208130) at syscall+0x4c3 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7ee878b5750, count: -9 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff800027207aa0 rbx 0xffffffff829b9b8f cpu_info_full_primary+0x2b8f rdx 0xffff800000bd1480 rcx 0 rax 0xffff800029656a80 r8 0x101010101010101 r9 0x8080808080808080 r10 0xbfc3136793717316 r11 0x8e66253b0a167a9d r12 0xffffffff829b9990 cpu_info_full_primary+0x2990 r13 0 r14 0 r15 0x1 rip 0xffffffff824835f8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800027207a90 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor.1) pid=414678 stat=onproc flags process=10 proc=4000000 pri=32, usrpri=82, nice=20 forw=0xffffffffffffffff, list=0xffff800029656fc0,0xffff800029656550 process=0xffff8000ffff8c80 user=0xffff800027203000, vmspace=0xfffffd8070ebc8b0 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 48706 159413 41643 32767 7 0x10 syz-executor.1 *48706 414678 41643 32767 7 0x4000010 syz-executor.1 41726 392260 37731 32767 2 0x10 syz-executor.4 41726 453050 37731 32767 3 0x4000090 fsleep syz-executor.4 94727 390301 82490 32767 2 0x10 syz-executor.6 94727 89453 82490 32767 3 0x4000090 fsleep syz-executor.6 51688 291120 76288 32767 3 0x90 nanoslp syz-executor.3 51688 348173 76288 32767 3 0x4000090 fsleep syz-executor.3 51688 390570 76288 32767 3 0x4000090 fsleep syz-executor.3 51688 31910 76288 32767 3 0x4000090 fsleep syz-executor.3 25025 216184 47740 32767 2 0x10 syz-executor.5 25025 72620 47740 32767 3 0x4000090 fsleep syz-executor.5 6609 251851 91933 32767 3 0x90 nanoslp syz-executor.0 6609 278513 91933 32767 2 0x4000010 syz-executor.0 6609 418612 91933 32767 3 0x4000090 fsleep syz-executor.0 6609 363126 91933 32767 3 0x4000090 fsleep syz-executor.0 37731 76359 8684 32767 3 0x90 nanoslp syz-executor.4 8684 512301 3907 0 3 0x82 wait syz-executor.4 91933 354475 99719 32767 3 0x90 nanoslp syz-executor.0 99719 373040 3907 0 3 0x82 wait syz-executor.0 98837 290616 95036 32767 3 0x90 nanoslp syz-executor.2 95036 387836 3907 0 3 0x82 wait syz-executor.2 51623 95408 0 0 3 0x14200 bored sosplice 82490 72424 44580 32767 2 0x10 syz-executor.6 8101 341365 52991 32767 3 0x90 nanoslp syz-executor.7 44580 96924 3907 0 3 0x82 wait syz-executor.6 47740 42623 47964 32767 3 0x90 nanoslp syz-executor.5 52991 328138 3907 0 3 0x82 wait syz-executor.7 47964 224456 3907 0 3 0x82 wait syz-executor.5 41643 282829 5356 32767 3 0x90 nanoslp syz-executor.1 76288 335570 50186 32767 3 0x90 nanoslp syz-executor.3 50186 136223 3907 0 3 0x82 wait syz-executor.3 5356 323795 3907 0 3 0x82 wait syz-executor.1 3907 27237 43206 0 3 0x82 thrsleep syz-fuzzer 3907 321614 43206 0 3 0x4000082 thrsleep syz-fuzzer 3907 38386 43206 0 3 0x4000082 wait syz-fuzzer 3907 514364 43206 0 3 0x4000082 wait syz-fuzzer 3907 225334 43206 0 3 0x4000082 thrsleep syz-fuzzer 3907 33502 43206 0 3 0x4000082 wait syz-fuzzer 3907 510017 43206 0 3 0x4000082 thrsleep syz-fuzzer 3907 397937 43206 0 3 0x4000082 thrsleep syz-fuzzer 3907 255025 43206 0 3 0x4000082 wait syz-fuzzer 3907 84605 43206 0 3 0x4000082 wait syz-fuzzer 3907 511867 43206 0 3 0x4000082 wait syz-fuzzer 3907 486122 43206 0 3 0x4000082 thrsleep syz-fuzzer 3907 358690 43206 0 3 0x4000082 wait syz-fuzzer 3907 267898 43206 0 3 0x4000082 wait syz-fuzzer 3907 178709 43206 0 3 0x4000082 kqread syz-fuzzer 3907 334088 43206 0 3 0x4000082 thrsleep syz-fuzzer 43206 46625 48067 0 3 0x10008a sigsusp ksh 48067 153820 18369 0 3 0x9a kqread sshd 58756 54496 1 0 3 0x100083 ttyin getty 18369 402321 1 0 3 0x88 kqread sshd 1293 279513 9953 73 3 0x1100090 kqread syslogd 9953 243932 1 0 3 0x100082 netio syslogd 33050 277886 1 0 3 0x100080 kqread resolvd 38399 418321 40494 77 3 0x100092 kqread dhcpleased 8968 254849 40494 77 3 0x100092 kqread dhcpleased 40494 339085 1 0 3 0x80 kqread dhcpleased 42319 389305 0 0 3 0x14200 bored smr 5324 171089 0 0 2 0x14200 zerothread 11398 221956 0 0 3 0x14200 aiodoned aiodoned 19593 233124 0 0 3 0x14200 syncer update 19151 21974 0 0 3 0x14200 cleaner cleaner 23785 298761 0 0 3 0x14200 reaper reaper 43698 56464 0 0 3 0x14200 pgdaemon pagedaemon 80582 353366 0 0 3 0x14200 bored viomb 71920 234761 0 0 3 0x40014200 acpi0 acpi0 61357 40796 0 0 3 0x40014200 idle1 70549 477446 0 0 3 0x14200 bored softnet 98778 469847 0 0 3 0x14200 bored softnet 21802 265341 0 0 3 0x14200 bored softnet 80407 229029 0 0 3 0x14200 bored softnet 78929 221632 0 0 3 0x14200 bored systqmp 20381 378342 0 0 3 0x14200 bored systq 32843 84355 0 0 3 0x40014200 bored softclock 96503 288657 0 0 3 0x40014200 idle0 1 111782 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 48706 (syz-executor.1) thread 0xffff800029656a80 (414678) exclusive rwlock netlock r = 0 (0xffffffff829ae840) #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 10212 6412K 6419K 78643K 11346 0 pcb 13 12K 14K 78643K 17 0 rtable 242 6K 7K 78643K 1623 0 ifaddr 82 17K 17K 78643K 184 0 sysctl 3 1K 3K 78643K 15 0 counters 56 35K 35K 78643K 84 0 ioctlops 0 0K 2K 78643K 136 0 iov 0 0K 28K 78643K 1666 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1271 79K 79K 78643K 4228 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 9K 78643K 105 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 0K 78643K 3485 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 24 89K 117K 78643K 11899 0 sigio 0 0K 0K 78643K 184 0 proc 56 78K 115K 78643K 1860 0 subproc 104 6K 6K 78643K 286 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 1047 0 in_multi 99 6K 7K 78643K 400 0 ether_multi 1 0K 0K 78643K 58 0 mrt 1 0K 0K 78643K 1 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 253 1129K 1129K 78643K 253 0 exec 0 0K 2K 78643K 2329 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 370 91K 102K 78643K 73724 0 UVM aobj 131 4K 4K 78643K 131 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 265 0 NDP 11 0K 2K 78643K 69 0 temp 124 4726K 4854K 78643K 31253 0 kqueue 12 18K 30K 78643K 1137 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 120 846 0 843 9 8 1 3 0 8 0 rtentry 112 281 0 167 4 0 4 4 0 8 0 unpcb 144 9470 0 9455 107 106 1 10 0 8 0 syncache 296 123 0 123 24 23 1 1 0 8 1 tcpqe 32 83 0 83 15 14 1 1 0 8 1 tcpcb 768 12513 0 12506 258 253 5 31 0 8 4 arp 120 49 0 31 1 0 1 1 0 8 0 ipq 40 20 0 20 9 9 0 1 0 8 0 ipqe 40 141 0 141 9 9 0 1 0 8 0 inpcb 368 17697 0 17689 175 171 4 20 0 8 3 nd6 48 79 0 51 1 0 1 1 0 8 0 kcovpl 48 22 0 14 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 1137 0 657 31 0 31 31 0 8 0 art_table 32 1138 0 657 4 0 4 4 0 8 0 art_node 16 280 0 176 1 0 1 1 0 8 0 sysvmsgpl 40 39 0 33 1 0 1 1 0 8 0 semupl 112 3 0 3 1 1 0 1 0 8 0 semapl 112 3478 0 3468 1 0 1 1 0 8 0 shmpl 112 128 0 0 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 18337 0 16884 92 0 92 92 0 8 0 ffsino 272 18337 0 16884 98 0 98 98 0 8 0 nchpl 144 34415 0 32771 63 0 63 63 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 117838 0 117838 3 2 1 2 0 8 1 percpumem 16 54 0 14 1 0 1 1 0 8 0 kstatmem 264 50 0 28 2 0 2 2 0 8 0 scxspl 216 99430 0 99430 39 38 1 8 0 8 1 plimitpl 152 2659 0 2637 13 12 1 2 0 8 0 sigapl 424 12156 0 12101 7 0 7 7 0 8 0 futexpl 64 111015 0 111007 4 3 1 1 0 8 0 knotepl 120 746 0 0 12 2 10 10 0 8 0 kqueuepl 216 3170 0 3162 47 46 1 6 0 8 0 pipepl 320 3221 0 3193 83 75 8 9 0 8 5 fdescpl 496 12138 0 12103 6 0 6 6 0 8 0 filepl 152 87922 0 87684 159 144 15 21 0 8 5 lockfpl 104 1824 0 1821 2 1 1 2 0 8 0 lockfspl 48 413 0 410 1 0 1 1 0 8 0 sessionpl 144 37 0 21 1 0 1 1 0 8 0 pgrppl 48 72 0 56 1 0 1 1 0 8 0 ucredpl 104 17332 0 17314 1 0 1 1 0 8 0 zombiepl 144 12103 0 12101 1 0 1 1 0 8 0 processpl 1064 12156 0 12101 4 0 4 4 0 8 0 procpl 672 35726 0 35646 20 12 8 9 0 8 0 sosppl 168 186 0 186 11 10 1 1 0 8 1 sockpl 488 28313 0 28287 492 485 7 35 0 8 3 mcl64k 65536 34 0 0 4 1 3 3 0 8 0 mcl16k 16384 17 0 0 3 0 3 3 0 8 0 mcl12k 12288 17 0 0 2 0 2 2 0 8 0 mcl9k 9216 47 0 0 4 0 4 4 0 8 0 mcl8k 8192 25 0 0 4 1 3 3 0 8 0 mcl4k 4096 25 0 0 3 0 3 3 0 8 0 mcl2k2 2112 5 0 0 1 0 1 1 0 8 0 mcl2k 2048 410 0 0 40 10 30 40 0 8 0 mtagpl 96 22 0 0 1 0 1 1 0 8 0 mbufpl 256 1438 0 0 58 0 58 58 0 8 0 bufpl 288 23305 0 16972 453 0 453 453 0 8 0 anonpl 24 2563683 0 2550615 241 136 105 119 0 186 0 amapchunkpl 152 212864 0 212191 103 67 36 40 0 158 7 amappl16 200 44042 0 43657 231 208 23 42 0 8 0 amappl15 192 947 0 940 1 0 1 1 0 8 0 amappl14 184 82 0 78 1 0 1 1 0 8 0 amappl13 176 1894 0 1888 1 0 1 1 0 8 0 amappl12 168 3149 0 3137 1 0 1 1 0 8 0 amappl11 160 2139 0 2122 1 0 1 1 0 8 0 amappl10 152 116 0 111 1 0 1 1 0 8 0 amappl9 144 2965 0 2957 1 0 1 1 0 8 0 amappl8 136 2600 0 2436 6 0 6 6 0 8 0 amappl7 128 1700 0 1679 1 0 1 1 0 8 0 amappl6 120 2804 0 2787 2 1 1 2 0 8 0 amappl5 112 10403 0 10384 1 0 1 1 0 8 0 amappl4 104 5001 0 4965 3 1 2 2 0 8 0 amappl3 96 40430 0 40362 2 0 2 2 0 8 0 amappl2 88 2790 0 2745 2 0 2 2 0 8 0 amappl1 80 303038 0 302290 22 5 17 19 0 8 0 amappl 88 72190 0 71989 6 0 6 6 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 72 130 0 0 3 0 3 3 0 8 0 uaddrrnd 24 12139 0 12104 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 12139 0 12104 1 0 1 1 0 8 0 vmmpekpl 168 101692 0 101623 5 1 4 4 0 8 0 vmmpepl 168 1212419 0 1209518 305 169 136 146 0 357 2 vmsppl 368 12138 0 12104 4 0 4 4 0 8 0 rwobjpl 56 310450 0 302888 124 13 111 112 0 8 0 pdppl 4096 24285 0 24208 338 257 81 91 0 8 4 pvpl 32 4713218 0 4694853 523 318 205 256 0 265 22 pmappl 248 12138 0 12104 3 0 3 3 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 1313 0 444 26 0 26 26 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(ffffffff8257e05d) at panic+0x177 sys/kern/subr_prf.c:198 tcp_output(ffff800000bba900) at tcp_output+0x2cd2 sys/netinet/tcp_output.c:727 tcp_send(fffffd80671143f8,fffffd806730d500,0,fffffd807059ed00) at tcp_send+0xc4 sys/netinet/tcp_usrreq.c:944 sosend(fffffd80671143f8,0,ffff800027207e40,0,fffffd807059ed00,0) at sosend+0x62a pru_send sys/sys/protosw.h:331 [inline] sosend(fffffd80671143f8,0,ffff800027207e40,0,fffffd807059ed00,0) at sosend+0x62a sys/kern/uipc_socket.c:646 sendit(ffff800029656a80,5,ffff800027207fc0,0,ffff8000272080b0) at sendit+0x65d sys/kern/uipc_syscalls.c:694 sys_sendmsg(ffff800029656a80,ffff800027208068,ffff8000272080b0) at sys_sendmsg+0x198 sys/kern/uipc_syscalls.c:601 syscall(ffff800027208130) at syscall+0x4c3 mi_syscall sys/sys/syscall_mi.h:101 [inline] syscall(ffff800027208130) at syscall+0x4c3 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7ee878b5750, 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 end of kernel end trace frame: 0x7f7ffffe37e0, count: 12 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 end of kernel end trace frame: 0x7f7ffffe37e0, count: -3