login: panic: syn_cache_insert: bucketoverflow: impossible Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 135617 92851 0 0x2 0 1 syz-executor5992 *510129 61050 0 0x14000 0x200 0 softnet db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff821e4f24) at panic+0x15c sys/kern/subr_prf.c:207 syn_cache_insert(fffffd80780ffd70,ffff800000a0a880) at syn_cache_insert+0x9d4 sys/netinet/tcp_input.c:3235 syn_cache_add(ffff800020e38ec0,ffff800020e38e70,fffffd8007e06868,28,fffffd806f6deaf0,fffffd807f01e800) at syn_cache_add+0x6e9 tcpstat_inc sys/netinet/tcp_var.h:645 [inline] syn_cache_add(ffff800020e38ec0,ffff800020e38e70,fffffd8007e06868,28,fffffd806f6deaf0,fffffd807f01e800) at syn_cache_add+0x6e9 sys/netinet/tcp_input.c:3871 tcp_input(ffff800020e391d8,ffff800020e391e4,6,18) at tcp_input+0x3c67 sys/netinet/tcp_input.c:830 ip_deliver(ffff800020e391d8,ffff800020e391e4,6,18) at ip_deliver+0x353 sys/netinet/ip_input.c:668 ip6_input_if(ffff800020e391d8,ffff800020e391e4,29,0,ffff80000067a800) at ip6_input_if+0x17e1 ip6_ours sys/netinet6/ip6_input.c:538 [inline] ip6_input_if(ffff800020e391d8,ffff800020e391e4,29,0,ffff80000067a800) at ip6_input_if+0x17e1 sys/netinet6/ip6_input.c:471 ipv6_input(ffff80000067a800,fffffd807f01e800) at ipv6_input+0x48 sys/netinet6/ip6_input.c:171 if_input_local(ffff80000067a800,fffffd807f01e800,18) at if_input_local+0x121 sys/net/if.c:781 loinput(ffff80000067a800,fffffd807f01e800,0) at loinput+0x4f sys/net/if_loop.c:239 if_input_process(ffff80000067a800,ffff800020e39348) at if_input_process+0x10b if_ih_input sys/net/if.c:910 [inline] if_input_process(ffff80000067a800,ffff800020e39348) at if_input_process+0x10b sys/net/if.c:944 ifiq_process(ffff80000067abf8) at ifiq_process+0x80 sys/net/ifq.c:646 taskq_thread(ffff80000002b080) at taskq_thread+0x9c sys/kern/kern_task.c:369 end trace frame: 0x0, count: 2 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 syn_cache_insert: bucketoverflow: impossible ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff821e4f24) at panic+0x15c sys/kern/subr_prf.c:207 syn_cache_insert(fffffd80780ffd70,ffff800000a0a880) at syn_cache_insert+0x9d4 sys/netinet/tcp_input.c:3235 syn_cache_add(ffff800020e38ec0,ffff800020e38e70,fffffd8007e06868,28,fffffd806f6deaf0,fffffd807f01e800) at syn_cache_add+0x6e9 tcpstat_inc sys/netinet/tcp_var.h:645 [inline] syn_cache_add(ffff800020e38ec0,ffff800020e38e70,fffffd8007e06868,28,fffffd806f6deaf0,fffffd807f01e800) at syn_cache_add+0x6e9 sys/netinet/tcp_input.c:3871 tcp_input(ffff800020e391d8,ffff800020e391e4,6,18) at tcp_input+0x3c67 sys/netinet/tcp_input.c:830 ip_deliver(ffff800020e391d8,ffff800020e391e4,6,18) at ip_deliver+0x353 sys/netinet/ip_input.c:668 ip6_input_if(ffff800020e391d8,ffff800020e391e4,29,0,ffff80000067a800) at ip6_input_if+0x17e1 ip6_ours sys/netinet6/ip6_input.c:538 [inline] ip6_input_if(ffff800020e391d8,ffff800020e391e4,29,0,ffff80000067a800) at ip6_input_if+0x17e1 sys/netinet6/ip6_input.c:471 ipv6_input(ffff80000067a800,fffffd807f01e800) at ipv6_input+0x48 sys/netinet6/ip6_input.c:171 if_input_local(ffff80000067a800,fffffd807f01e800,18) at if_input_local+0x121 sys/net/if.c:781 loinput(ffff80000067a800,fffffd807f01e800,0) at loinput+0x4f sys/net/if_loop.c:239 if_input_process(ffff80000067a800,ffff800020e39348) at if_input_process+0x10b if_ih_input sys/net/if.c:910 [inline] if_input_process(ffff80000067a800,ffff800020e39348) at if_input_process+0x10b sys/net/if.c:944 ifiq_process(ffff80000067abf8) at ifiq_process+0x80 sys/net/ifq.c:646 taskq_thread(ffff80000002b080) at taskq_thread+0x9c sys/kern/kern_task.c:369 end trace frame: 0x0, count: -13 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff800020e38a40 rbx 0xffff800020e38af0 rdx 0x8b rcx 0x2 rax 0x1 r8 0xffffffff81f3c28f kprintf+0x16f r9 0x1 r10 0x2 r11 0x3a6ac3a7c0f5c585 r12 0x3000000008 r13 0xffff800020e38a50 r14 0x100 r15 0x1 rip 0xffffffff8149f5a8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020e38a30 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (softnet) pid=510129 stat=onproc flags process=14000 proc=200 pri=32, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff800020e184e0,0xffff800020e18010 process=0xffff800020e1ab88 user=0xffff800020e34000, vmspace=0xffffffff8267e568 estcpu=0, cpticks=1, pctcpu=0.1 user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 92851 135617 8952 0 7 0x2 syz-executor5992 92851 24 8952 0 3 0x4000082 netcon2 syz-executor5992 8952 111152 73746 0 3 0x10008a pause ksh 73746 495736 32846 0 3 0x92 select sshd 74929 140057 1 0 3 0x100083 ttyin getty 32846 296780 1 0 3 0x80 select sshd 13442 358398 16675 74 3 0x100092 bpf pflogd 16675 377445 1 0 3 0x80 netio pflogd 29083 252719 68027 73 3 0x100090 kqread syslogd 68027 462228 1 0 3 0x100082 netio syslogd 67825 356081 1 77 3 0x100090 poll dhclient 90844 105670 1 0 3 0x80 poll dhclient 1329 363142 0 0 3 0x14200 bored smr 23256 137046 0 0 2 0x14200 zerothread 48980 493395 0 0 3 0x14200 aiodoned aiodoned 9511 304072 0 0 3 0x14200 syncer update 59479 451722 0 0 3 0x14200 cleaner cleaner 14370 127740 0 0 3 0x14200 reaper reaper 15246 451015 0 0 3 0x14200 pgdaemon pagedaemon 95886 371729 0 0 3 0x14200 bored crynlk 2564 206539 0 0 3 0x14200 bored crypto 26269 463971 0 0 3 0x40014200 acpi0 acpi0 62338 164829 0 0 3 0x40014200 idle1 *61050 510129 0 0 7 0x14200 softnet 27311 230125 0 0 3 0x14200 bored systqmp 2437 428281 0 0 3 0x14200 bored systq 2980 436637 0 0 3 0x40014200 bored softclock 98808 476607 0 0 3 0x40014200 idle0 1 142221 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 61050 (softnet) thread 0xffff800020e18270 (510129) exclusive rwlock netlock r = 0 (0xffffffff824b7688) #0 witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4c7 sys/kern/subr_witness.c:1164 #1 if_input_process+0x85 sys/net/if.c:943 #2 ifiq_process+0x80 sys/net/ifq.c:646 #3 taskq_thread+0x9c sys/kern/kern_task.c:369 #4 proc_trampoline+0x1c shared rwlock softnet r = 0 (0xffff80000002b0e0) #0 witness_lock+0x4c7 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4c7 sys/kern/subr_witness.c:1164 #1 taskq_thread+0x8f sys/kern/kern_task.c:368 #2 proc_trampoline+0x1c ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9463 6393K 6394K 78643K 10556 0 pcb 13 8K 8K 78643K 13 0 rtable 61 2K 2K 78643K 127 0 ifaddr 29 8K 8K 78643K 30 0 counters 39 33K 33K 78643K 39 0 ioctlops 0 0K 4K 78643K 1467 0 mount 1 1K 1K 78643K 1 0 vnodes 1183 74K 75K 78643K 1188 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 1824 197K 290K 78643K 13058 0 file desc 1 0K 0K 78643K 1 0 proc 59 63K 71K 78643K 358 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 19 95K 95K 78643K 19 0 exec 0 0K 1K 78643K 177 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 62 3K 3K 78643K 798 0 UVM aobj 2 2K 2K 78643K 2 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 NDP 4 0K 0K 78643K 4 0 temp 24 3029K 3093K 78643K 1670 0 kqueue 2 2K 2K 78643K 2 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 arp 64 2 0 0 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 15 0 13 1 0 1 1 0 8 0 rtentry 112 23 0 1 1 0 1 1 0 8 0 unpcb 120 29 0 19 1 0 1 1 0 8 0 syncache 264 6 0 5 2 1 1 1 0 8 0 tcpcb 544 10 0 5 1 0 1 1 0 8 0 inpcb 280 31 0 23 1 0 1 1 0 8 0 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 9 0 0 1 0 1 1 0 8 0 pfstkey 112 9 0 0 1 0 1 1 0 8 0 pfstate 328 9 0 0 1 0 1 1 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 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 1400 0 16 87 0 87 87 0 8 0 ffsino 272 1400 0 16 93 0 93 93 0 8 0 nchpl 144 1574 0 32 58 0 58 58 0 8 0 uvmvnodes 72 1410 0 0 26 0 26 26 0 8 0 vnodes 208 1410 0 0 75 0 75 75 0 8 0 namei 1024 3777 0 3777 2 1 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 scxspl 192 2816 0 2816 2 1 1 2 0 8 1 plimitpl 152 14 0 8 1 0 1 1 0 8 0 sigapl 424 220 0 192 4 0 4 4 0 8 0 knotepl 112 5 0 0 1 0 1 1 0 8 0 kqueuepl 144 1 0 0 1 0 1 1 0 8 0 pipelkpl 48 64 0 60 2 1 1 1 0 8 0 pipepl 120 128 0 121 2 1 1 1 0 8 0 fdescpl 496 205 0 192 3 0 3 3 0 8 0 filepl 152 963 0 913 2 0 2 2 0 8 0 lockfpl 104 5 0 4 1 0 1 1 0 8 0 lockfspl 48 3 0 2 1 0 1 1 0 8 0 sessionpl 112 18 0 9 1 0 1 1 0 8 0 pgrppl 48 18 0 9 1 0 1 1 0 8 0 ucredpl 96 62 0 53 1 0 1 1 0 8 0 zombiepl 144 192 0 192 2 1 1 1 0 8 1 processpl 984 220 0 192 4 0 4 4 0 8 0 procpl 624 221 0 192 3 0 3 3 0 8 0 sockpl 400 75 0 55 2 0 2 2 0 8 0 mcl4k 4096 2 0 0 1 0 1 1 0 8 0 mcl2k 2048 80 0 0 10 0 10 10 0 8 0 mtagpl 80 1 0 0 1 0 1 1 0 8 0 mbufpl 256 96 0 0 6 0 6 6 0 8 0 bufpl 280 1901 0 91 130 0 130 130 0 8 0 anonpl 16 19250 0 17997 8 2 6 7 0 124 0 amapchunkpl 152 527 0 487 2 0 2 2 0 158 0 amappl16 192 85 0 81 1 0 1 1 0 8 0 amappl15 184 1 0 0 1 0 1 1 0 8 0 amappl14 176 22 0 19 1 0 1 1 0 8 0 amappl13 168 14 0 13 2 1 1 1 0 8 0 amappl12 160 3 0 3 1 1 0 1 0 8 0 amappl11 152 53 0 38 1 0 1 1 0 8 0 amappl10 144 12 0 10 1 0 1 1 0 8 0 amappl9 136 231 0 230 1 0 1 1 0 8 0 amappl8 128 238 0 235 1 0 1 1 0 8 0 amappl7 120 90 0 82 1 0 1 1 0 8 0 amappl6 112 14 0 14 1 1 0 1 0 8 0 amappl5 104 146 0 132 1 0 1 1 0 8 0 amappl4 96 462 0 438 1 0 1 1 0 8 0 amappl3 88 97 0 91 1 0 1 1 0 8 0 amappl2 80 781 0 720 3 1 2 2 0 8 0 amappl1 72 13848 0 13417 15 5 10 15 0 8 0 amappl 80 410 0 388 1 0 1 1 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 1 0 0 1 0 1 1 0 8 0 uaddrrnd 24 205 0 192 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 205 0 192 1 0 1 1 0 8 0 vmmpekpl 168 5472 0 5450 2 0 2 2 0 8 0 vmmpepl 168 29237 0 28367 48 9 39 47 0 357 1 vmsppl 368 204 0 192 2 0 2 2 0 8 0 pdppl 4096 418 0 384 6 0 6 6 0 8 0 pvpl 32 79370 0 76374 32 4 28 28 0 265 3 pmappl 232 204 0 192 1 0 1 1 0 8 0 extentpl 40 53 0 36 1 0 1 1 0 8 0 phpool 112 228 0 4 7 0 7 7 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:398 panic(ffffffff821e4f24) at panic+0x15c sys/kern/subr_prf.c:207 syn_cache_insert(fffffd80780ffd70,ffff800000a0a880) at syn_cache_insert+0x9d4 sys/netinet/tcp_input.c:3235 syn_cache_add(ffff800020e38ec0,ffff800020e38e70,fffffd8007e06868,28,fffffd806f6deaf0,fffffd807f01e800) at syn_cache_add+0x6e9 tcpstat_inc sys/netinet/tcp_var.h:645 [inline] syn_cache_add(ffff800020e38ec0,ffff800020e38e70,fffffd8007e06868,28,fffffd806f6deaf0,fffffd807f01e800) at syn_cache_add+0x6e9 sys/netinet/tcp_input.c:3871 tcp_input(ffff800020e391d8,ffff800020e391e4,6,18) at tcp_input+0x3c67 sys/netinet/tcp_input.c:830 ip_deliver(ffff800020e391d8,ffff800020e391e4,6,18) at ip_deliver+0x353 sys/netinet/ip_input.c:668 ip6_input_if(ffff800020e391d8,ffff800020e391e4,29,0,ffff80000067a800) at ip6_input_if+0x17e1 ip6_ours sys/netinet6/ip6_input.c:538 [inline] ip6_input_if(ffff800020e391d8,ffff800020e391e4,29,0,ffff80000067a800) at ip6_input_if+0x17e1 sys/netinet6/ip6_input.c:471 ipv6_input(ffff80000067a800,fffffd807f01e800) at ipv6_input+0x48 sys/netinet6/ip6_input.c:171 if_input_local(ffff80000067a800,fffffd807f01e800,18) at if_input_local+0x121 sys/net/if.c:781 loinput(ffff80000067a800,fffffd807f01e800,0) at loinput+0x4f sys/net/if_loop.c:239 if_input_process(ffff80000067a800,ffff800020e39348) at if_input_process+0x10b if_ih_input sys/net/if.c:910 [inline] if_input_process(ffff80000067a800,ffff800020e39348) at if_input_process+0x10b sys/net/if.c:944 ifiq_process(ffff80000067abf8) at ifiq_process+0x80 sys/net/ifq.c:646 taskq_thread(ffff80000002b080) at taskq_thread+0x9c sys/kern/kern_task.c:369 end trace frame: 0x0, count: -13 ddb{0}> machine ddbcpu 1 Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp x86_ipi_db(ffff800020e00ff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:352 x86_ipi_handler() at x86_ipi_handler+0xc6 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23 end of kernel end trace frame: 0x7f7ffffe0ea0, count: 12 ddb{1}> trace x86_ipi_db(ffff800020e00ff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:352 x86_ipi_handler() at x86_ipi_handler+0xc6 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23 end of kernel end trace frame: 0x7f7ffffe0ea0, count: -3 ddb{1}>