panic: tcp_output Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 14151 58302 32767 0x10 0 1 syz-executor.6 * 59155 29812 32767 0x10 0x4000000 0 syz-executor.2 db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff8257befc) at panic+0x177 sys/kern/subr_prf.c:198 tcp_output(ffff800000c712e8) at tcp_output+0x2cd2 sys/netinet/tcp_output.c:727 tcp_send(fffffd80715dd008,fffffd806d50fe00,0,fffffd8069228400) at tcp_send+0xc4 sys/netinet/tcp_usrreq.c:953 sosend(fffffd80715dd008,0,ffff8000295f6560,0,fffffd8069228400,0) at sosend+0x62a pru_send sys/sys/protosw.h:331 [inline] sosend(fffffd80715dd008,0,ffff8000295f6560,0,fffffd8069228400,0) at sosend+0x62a sys/kern/uipc_socket.c:646 sendit(ffff8000212b17a0,5,ffff8000295f66e0,0,ffff8000295f67d0) at sendit+0x65d sys/kern/uipc_syscalls.c:694 sys_sendmsg(ffff8000212b17a0,ffff8000295f6788,ffff8000295f67d0) at sys_sendmsg+0x198 sys/kern/uipc_syscalls.c:601 syscall(ffff8000295f6850) at syscall+0x4c3 mi_syscall sys/sys/syscall_mi.h:101 [inline] syscall(ffff8000295f6850) at syscall+0x4c3 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xec8e4a443f0, 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(ffffffff8257befc) at panic+0x177 sys/kern/subr_prf.c:198 tcp_output(ffff800000c712e8) at tcp_output+0x2cd2 sys/netinet/tcp_output.c:727 tcp_send(fffffd80715dd008,fffffd806d50fe00,0,fffffd8069228400) at tcp_send+0xc4 sys/netinet/tcp_usrreq.c:953 sosend(fffffd80715dd008,0,ffff8000295f6560,0,fffffd8069228400,0) at sosend+0x62a pru_send sys/sys/protosw.h:331 [inline] sosend(fffffd80715dd008,0,ffff8000295f6560,0,fffffd8069228400,0) at sosend+0x62a sys/kern/uipc_socket.c:646 sendit(ffff8000212b17a0,5,ffff8000295f66e0,0,ffff8000295f67d0) at sendit+0x65d sys/kern/uipc_syscalls.c:694 sys_sendmsg(ffff8000212b17a0,ffff8000295f6788,ffff8000295f67d0) at sys_sendmsg+0x198 sys/kern/uipc_syscalls.c:601 syscall(ffff8000295f6850) at syscall+0x4c3 mi_syscall sys/sys/syscall_mi.h:101 [inline] syscall(ffff8000295f6850) at syscall+0x4c3 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xec8e4a443f0, count: -9 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff8000295f61c0 rbx 0xffffffff82934b8f cpu_info_full_primary+0x2b8f rdx 0xffff800000bd19c0 rcx 0 rax 0xffff8000212b17a0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x9a6e5aa78e14ec87 r11 0xe089d4666a26db90 r12 0xffffffff82934990 cpu_info_full_primary+0x2990 r13 0 r14 0 r15 0x1 rip 0xffffffff823fc058 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000295f61b0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor.2) pid=59155 stat=onproc flags process=10 proc=4000000 pri=82, usrpri=82, nice=20 forw=0xffffffffffffffff, list=0xffff80002c252d20,0xffff8000212b1510 process=0xffff80002129b1f0 user=0xffff8000295f1000, vmspace=0xfffffd8067e96a28 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 58302 14151 59041 32767 7 0x10 syz-executor.6 58302 438362 59041 32767 2 0x4000090 syz-executor.6 40143 238590 20549 32767 2 0x10 syz-executor.1 40143 297135 20549 32767 3 0x4000090 fsleep syz-executor.1 40143 249827 20549 32767 3 0x4000090 fsleep syz-executor.1 40143 498513 20549 32767 3 0x4000090 fsleep syz-executor.1 56435 327874 59380 32767 2 0x10 syz-executor.3 56435 269477 59380 32767 3 0x4000090 fsleep syz-executor.3 51007 95309 73009 32767 2 0x10 syz-executor.7 51007 237794 73009 32767 3 0x4000090 fsleep syz-executor.7 51007 513304 73009 32767 3 0x4000090 fsleep syz-executor.7 45652 419392 66190 32767 3 0x90 nanoslp syz-executor.5 45652 389336 66190 32767 3 0x4000090 netcon syz-executor.5 45652 251333 66190 32767 3 0x4000090 fsleep syz-executor.5 29812 269708 35102 32767 2 0x10 syz-executor.2 *29812 59155 35102 32767 7 0x4000010 syz-executor.2 63603 53223 7325 32767 2 0x10 syz-executor.4 63603 385965 7325 32767 3 0x4000090 netio syz-executor.4 63603 466276 7325 32767 3 0x4000090 fsleep syz-executor.4 67169 83943 49923 32767 3 0x90 nanoslp syz-executor.0 67169 467988 49923 32767 3 0x4000090 netcon syz-executor.0 67169 436808 49923 32767 3 0x4000090 netcon syz-executor.0 67169 423437 49923 32767 3 0x4000090 fsleep syz-executor.0 20549 200600 25982 32767 3 0x90 nanoslp syz-executor.1 25982 124220 18123 0 3 0x82 wait syz-executor.1 7325 341181 56049 32767 3 0x90 nanoslp syz-executor.4 56049 392409 18123 0 3 0x82 wait syz-executor.4 86912 480072 0 0 3 0x14200 bored sosplice 73009 214530 58573 32767 3 0x90 nanoslp syz-executor.7 58573 456929 18123 0 3 0x82 wait syz-executor.7 66190 196812 97870 32767 3 0x90 nanoslp syz-executor.5 97870 78569 18123 0 3 0x82 wait syz-executor.5 59041 45789 51022 32767 3 0x90 nanoslp syz-executor.6 51022 416353 18123 0 3 0x82 wait syz-executor.6 59380 115788 4928 32767 3 0x90 nanoslp syz-executor.3 35102 430955 57022 32767 3 0x90 nanoslp syz-executor.2 49923 429460 52732 32767 3 0x90 nanoslp syz-executor.0 4928 168186 18123 0 3 0x82 wait syz-executor.3 52732 27800 18123 0 3 0x82 wait syz-executor.0 57022 46039 18123 0 3 0x82 wait syz-executor.2 18123 181760 60887 0 3 0x82 wait syz-fuzzer 18123 105510 60887 0 3 0x4000082 nanoslp syz-fuzzer 18123 92209 60887 0 3 0x4000082 wait syz-fuzzer 18123 519729 60887 0 3 0x4000082 thrsleep syz-fuzzer 18123 53001 60887 0 3 0x4000082 kqread syz-fuzzer 18123 22895 60887 0 3 0x4000082 thrsleep syz-fuzzer 18123 385500 60887 0 3 0x4000082 wait syz-fuzzer 18123 309116 60887 0 3 0x4000082 thrsleep syz-fuzzer 18123 81725 60887 0 3 0x4000082 wait syz-fuzzer 18123 188614 60887 0 3 0x4000082 wait syz-fuzzer 18123 286933 60887 0 3 0x4000082 wait syz-fuzzer 18123 203252 60887 0 3 0x4000082 wait syz-fuzzer 18123 73839 60887 0 3 0x4000082 thrsleep syz-fuzzer 18123 12343 60887 0 3 0x4000082 wait syz-fuzzer 18123 174470 60887 0 3 0x4000082 thrsleep syz-fuzzer 18123 202225 60887 0 3 0x4000082 nanoslp syz-fuzzer 60887 519311 91093 0 3 0x10008a sigsusp ksh 91093 82271 46238 0 3 0x9a kqread sshd 64682 491175 1 0 3 0x100083 ttyin getty 46238 104092 1 0 3 0x88 kqread sshd 15337 411563 92162 73 3 0x1100090 kqread syslogd 92162 212960 1 0 3 0x100082 netio syslogd 50491 440333 1 0 3 0x100080 kqread resolvd 51989 238356 56495 77 3 0x100092 kqread dhcpleased 53269 295225 56495 77 3 0x100092 kqread dhcpleased 56495 339567 1 0 3 0x80 kqread dhcpleased 98165 145197 0 0 3 0x14200 bored smr 19655 166172 0 0 2 0x14200 zerothread 5344 102627 0 0 3 0x14200 aiodoned aiodoned 62978 286384 0 0 3 0x14200 syncer update 46598 214265 0 0 3 0x14200 cleaner cleaner 6054 289428 0 0 3 0x14200 reaper reaper 37702 457929 0 0 3 0x14200 pgdaemon pagedaemon 39655 358379 0 0 3 0x14200 bored viomb 61293 237397 0 0 3 0x40014200 acpi0 acpi0 49915 137862 0 0 3 0x40014200 idle1 21691 448012 0 0 3 0x14200 bored softnet 51755 522277 0 0 3 0x14200 bored softnet 25436 21692 0 0 3 0x14200 bored softnet 13746 520889 0 0 3 0x14200 bored softnet 18417 77209 0 0 3 0x14200 bored systqmp 7000 242728 0 0 3 0x14200 bored systq 93082 302827 0 0 3 0x40014200 bored softclock 46743 231919 0 0 3 0x40014200 idle0 1 273786 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 58302 (syz-executor.6) thread 0xffff800021258000 (14151) exclusive rwlock vmmaplk r = 0 (0xfffffd806c5c98c8) #0 witness_lock+0x44d #1 rw_enter+0x3e1 sys/kern/kern_rwlock.c:310 #2 vm_map_lock_ln+0xda sys/uvm/uvm_map.c:5209 #3 uvm_mapanon+0x22f sys/uvm/uvm_map.c:783 #4 sys_mmap+0x870 uvm_mmapanon sys/uvm/uvm_mmap.c:986 [inline] #4 sys_mmap+0x870 sys/uvm/uvm_mmap.c:425 #5 syscall+0x435 mi_syscall sys/sys/syscall_mi.h:101 [inline] #5 syscall+0x435 sys/arch/amd64/amd64/trap.c:585 #6 Xsyscall+0x128 exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82a07c48) #0 witness_lock+0x44d #1 syscall+0x41d mi_syscall sys/sys/syscall_mi.h:100 [inline] #1 syscall+0x41d sys/arch/amd64/amd64/trap.c:585 #2 Xsyscall+0x128 Process 29812 (syz-executor.2) thread 0xffff8000212b17a0 (59155) exclusive rwlock netlock r = 0 (0xffffffff8292fbb0) #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 10210 6412K 6419K 78643K 11314 0 pcb 13 12K 14K 78643K 17 0 rtable 244 6K 7K 78643K 906 0 ifaddr 82 16K 16K 78643K 112 0 sysctl 3 1K 1K 78643K 7 0 counters 56 35K 35K 78643K 64 0 ioctlops 0 0K 2K 78643K 173 0 iov 0 0K 24K 78643K 6614 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1271 79K 79K 78643K 2487 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 9K 78643K 78 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 0K 78643K 1373 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12548 0 file desc 26 97K 109K 78643K 5579 0 sigio 0 0K 0K 78643K 164 0 proc 59 91K 103K 78643K 980 0 subproc 104 6K 6K 78643K 156 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 1 0K 0K 78643K 377 0 in_multi 99 6K 6K 78643K 191 0 ether_multi 1 0K 0K 78643K 17 0 mrt 2 0K 0K 78643K 2 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 241 1076K 1076K 78643K 241 0 exec 0 0K 2K 78643K 1718 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 320 90K 100K 78643K 37256 0 UVM aobj 131 8K 8K 78643K 136 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 199 0 NDP 11 0K 2K 78643K 39 0 temp 124 4726K 4854K 78643K 17450 0 kqueue 12 18K 26K 78643K 558 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 120 431 0 428 5 4 1 3 0 8 0 rtentry 112 162 0 47 4 0 4 4 0 8 0 unpcb 144 4265 0 4245 45 44 1 8 0 8 0 syncache 296 67 0 67 16 15 1 1 0 8 1 tcpqe 32 132 0 132 10 9 1 1 0 8 1 tcpcb 768 2279 0 2256 87 78 9 15 0 8 6 arp 120 27 0 9 1 0 1 1 0 8 0 ipq 40 8 0 7 5 4 1 1 0 8 0 ipqe 40 59 0 58 5 4 1 1 0 8 0 inpcb 368 4804 0 4780 98 91 7 14 0 8 4 nd6 48 42 0 13 1 0 1 1 0 8 0 kcovpl 48 12 0 4 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 664 0 189 31 1 30 31 0 8 0 art_table 32 665 0 189 4 0 4 4 0 8 0 art_node 16 161 0 56 1 0 1 1 0 8 0 sysvmsgpl 40 23 0 4 1 0 1 1 0 8 0 semupl 112 2 0 2 1 1 0 1 0 8 0 semapl 112 1369 0 1359 1 0 1 1 0 8 0 shmpl 112 133 0 5 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 8968 0 7537 90 0 90 90 0 8 0 ffsino 272 8968 0 7537 96 0 96 96 0 8 0 nchpl 144 16497 0 14857 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 61792 0 61792 2 1 1 2 0 8 1 percpumem 16 44 0 4 1 0 1 1 0 8 0 kstatmem 264 30 0 8 2 0 2 2 0 8 0 scxspl 216 49670 0 49670 19 17 2 8 0 8 2 plimitpl 152 1005 0 982 3 2 1 2 0 8 0 sigapl 424 5858 0 5803 7 0 7 7 0 8 0 futexpl 64 53539 0 53530 2 1 1 1 0 8 0 knotepl 120 616 0 0 17 0 17 17 0 8 0 kqueuepl 216 1872 0 1864 32 31 1 8 0 8 0 pipepl 320 2145 0 2117 46 38 8 9 0 8 5 fdescpl 496 5840 0 5803 7 1 6 6 0 8 0 filepl 152 44832 0 44579 90 75 15 19 0 8 4 lockfpl 104 667 0 665 1 0 1 1 0 8 0 lockfspl 48 203 0 201 1 0 1 1 0 8 0 sessionpl 144 27 0 11 1 0 1 1 0 8 0 pgrppl 48 116 0 100 1 0 1 1 0 8 0 ucredpl 104 7297 0 7279 1 0 1 1 0 8 0 zombiepl 144 5803 0 5803 1 0 1 1 0 8 1 processpl 1064 5858 0 5803 4 0 4 4 0 8 0 procpl 672 17536 0 17451 16 8 8 9 0 8 0 sosppl 168 107 0 106 7 6 1 1 0 8 0 sockpl 488 9818 0 9769 249 237 12 29 0 8 5 mcl64k 65536 26 0 0 3 0 3 3 0 8 0 mcl16k 16384 17 0 0 3 0 3 3 0 8 0 mcl12k 12288 30 0 0 2 0 2 2 0 8 0 mcl9k 9216 17 0 0 2 0 2 2 0 8 0 mcl8k 8192 25 0 0 4 1 3 3 0 8 0 mcl4k 4096 27 0 0 3 1 2 3 0 8 0 mcl2k2 2112 7 0 0 1 0 1 1 0 8 0 mcl2k 2048 276 0 0 25 4 21 25 0 8 0 mtagpl 96 3 0 0 1 0 1 1 0 8 0 mbufpl 256 613 0 0 30 0 30 30 0 8 0 bufpl 288 12172 0 5842 453 0 453 453 0 8 0 anonpl 24 5118204 0 5103765 434 249 185 220 0 186 26 amapchunkpl 152 131057 0 130313 85 54 31 44 0 158 2 amappl16 200 246678 0 246273 1260 1201 59 91 0 8 20 amappl15 192 1410 0 1400 1 0 1 1 0 8 0 amappl14 184 39 0 35 1 0 1 1 0 8 0 amappl13 176 1083 0 1080 1 0 1 1 0 8 0 amappl12 168 1196 0 1187 1 0 1 1 0 8 0 amappl11 160 100 0 82 1 0 1 1 0 8 0 amappl10 152 1382 0 1371 1 0 1 1 0 8 0 amappl9 144 932 0 926 1 0 1 1 0 8 0 amappl8 136 984 0 890 5 1 4 4 0 8 0 amappl7 128 356 0 337 1 0 1 1 0 8 0 amappl6 120 671 0 653 2 1 1 2 0 8 0 amappl5 112 5792 0 5766 1 0 1 1 0 8 0 amappl4 104 1065 0 1036 1 0 1 1 0 8 0 amappl3 96 19178 0 19100 3 1 2 3 0 8 0 amappl2 88 2986 0 2941 4 2 2 2 0 8 0 amappl1 80 147461 0 146654 19 2 17 19 0 8 0 amappl 88 36323 0 36119 5 0 5 5 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 72 135 0 5 3 0 3 3 0 8 0 uaddrrnd 24 5841 0 5804 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 5841 0 5804 1 0 1 1 0 8 0 vmmpekpl 168 56261 0 56211 3 0 3 3 0 8 0 vmmpepl 168 806921 0 803881 370 198 172 186 0 357 35 vmsppl 368 5840 0 5804 4 0 4 4 0 8 0 rwobjpl 56 382652 0 375078 166 46 120 125 0 8 2 pdppl 4096 11689 0 11608 218 137 81 87 0 8 0 pvpl 32 6485671 0 6465557 564 269 295 336 0 265 57 pmappl 248 5840 0 5804 4 1 3 3 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 1067 0 238 24 0 24 24 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(ffffffff8257befc) at panic+0x177 sys/kern/subr_prf.c:198 tcp_output(ffff800000c712e8) at tcp_output+0x2cd2 sys/netinet/tcp_output.c:727 tcp_send(fffffd80715dd008,fffffd806d50fe00,0,fffffd8069228400) at tcp_send+0xc4 sys/netinet/tcp_usrreq.c:953 sosend(fffffd80715dd008,0,ffff8000295f6560,0,fffffd8069228400,0) at sosend+0x62a pru_send sys/sys/protosw.h:331 [inline] sosend(fffffd80715dd008,0,ffff8000295f6560,0,fffffd8069228400,0) at sosend+0x62a sys/kern/uipc_socket.c:646 sendit(ffff8000212b17a0,5,ffff8000295f66e0,0,ffff8000295f67d0) at sendit+0x65d sys/kern/uipc_syscalls.c:694 sys_sendmsg(ffff8000212b17a0,ffff8000295f6788,ffff8000295f67d0) at sys_sendmsg+0x198 sys/kern/uipc_syscalls.c:601 syscall(ffff8000295f6850) at syscall+0x4c3 mi_syscall sys/sys/syscall_mi.h:101 [inline] syscall(ffff8000295f6850) at syscall+0x4c3 sys/arch/amd64/amd64/trap.c:585 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xec8e4a443f0, 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: 0x7f7ffffbb7c0, 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: 0x7f7ffffbb7c0, count: -3