panic(ffffffff821ec365) at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff8266e370) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff8266e370) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff8266e370,1) at pool_get+0x91 sys/kern/subr_pool.c:572 m_gethdr(1,1) at m_gethdr+0x4c sys/kern/uipc_mbuf.c:283 m_getuio(ffff800021bb8d58,1,2400,ffff800021bb8e20) at m_getuio+0xe4 sys/kern/uipc_socket.c:581 sosend(fffffd806653d4d8,fffffd806908dc00,ffff800021bb8e20,0,0,0) at sosend+0x54e sys/kern/uipc_socket.c:536 sendit(ffff800020aa8018,7,ffff800021bb8f80,0,ffff800021bb9070) at sendit+0x52b sys/kern/uipc_syscalls.c:657 sys_sendmsg(ffff800020aa8018,ffff800021bb9028,ffff800021bb9070) at sys_sendmsg+0x1a4 sys/kern/uipc_syscalls.c:562 syscall(ffff800021bb90f0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800021bb90f0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xf4289bd4aa0, count: 4 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{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic pool_cache_item_magic_check: mbufpl cpu free list modified: item addr 0xfffffd806cbd1900+16 0x0!=0x65f36cf449d6ffac ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff821ec365) at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff8266e370) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff8266e370) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff8266e370,1) at pool_get+0x91 sys/kern/subr_pool.c:572 m_gethdr(1,1) at m_gethdr+0x4c sys/kern/uipc_mbuf.c:283 m_getuio(ffff800021bb8d58,1,2400,ffff800021bb8e20) at m_getuio+0xe4 sys/kern/uipc_socket.c:581 sosend(fffffd806653d4d8,fffffd806908dc00,ffff800021bb8e20,0,0,0) at sosend+0x54e sys/kern/uipc_socket.c:536 sendit(ffff800020aa8018,7,ffff800021bb8f80,0,ffff800021bb9070) at sendit+0x52b sys/kern/uipc_syscalls.c:657 sys_sendmsg(ffff800020aa8018,ffff800021bb9028,ffff800021bb9070) at sys_sendmsg+0x1a4 sys/kern/uipc_syscalls.c:562 syscall(ffff800021bb90f0) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800021bb90f0) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:570 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xf4289bd4aa0, count: -11 ddb{1}> show registers rdi 0xffffffff818ed047 db_enter+0x17 rsi 0x5171 __ALIGN_SIZE+0x4171 rbp 0xffff800021bb8a80 rbx 0xffff800021bb8b30 rdx 0x5172 __ALIGN_SIZE+0x4172 rcx 0xffff800022d94000 rax 0xffff800022d94000 r8 0xffffffff8148f46f kprintf+0x16f r9 0x1 r10 0x25 r11 0xe57f80316c96ef6f r12 0x3000000008 r13 0xffff800021bb8a90 r14 0x100 r15 0x1 rip 0xffffffff818ed048 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800021bb8a70 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.1) pid=21205 stat=onproc flags process=10 proc=4000000 pri=32, usrpri=73, nice=20 forw=0xffffffffffffffff, list=0xffff800020aa9878,0xffff800020aa9138 process=0xffff800020ac23e8 user=0xffff800021bb4000, vmspace=0xfffffd807f000450 estcpu=23, cpticks=3, pctcpu=0.0 user=0, sys=2, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 4326 107440 89871 60929 2 0x10 syz-executor.1 * 4326 21205 89871 60929 7 0x4000010 syz-executor.1 4326 190214 89871 60929 3 0x4000090 fsleep syz-executor.1 4326 417152 89871 60929 3 0x4000090 fsleep syz-executor.1 61167 337863 17519 0 2 0 syz-executor.0 61167 498485 17519 0 3 0x4000080 ttyout syz-executor.0 61167 453579 17519 0 3 0x4000080 fsleep syz-executor.0 61167 197467 17519 0 3 0x4000080 fsleep syz-executor.0 49446 410255 0 0 3 0x14200 bored sosplice 89871 352638 80924 0 2 0x482 syz-executor.1 17519 265516 80924 0 3 0x82 nanosleep syz-executor.0 80924 235949 21079 0 3 0x82 kqread syz-fuzzer 80924 477841 21079 0 3 0x4000082 thrsleep syz-fuzzer 80924 79269 21079 0 3 0x4000082 thrsleep syz-fuzzer 80924 77758 21079 0 3 0x4000082 thrsleep syz-fuzzer 80924 297675 21079 0 3 0x4000082 thrsleep syz-fuzzer 80924 252940 21079 0 3 0x4000082 thrsleep syz-fuzzer 80924 316945 21079 0 3 0x4000082 thrsleep syz-fuzzer 80924 180232 21079 0 3 0x4000082 thrsleep syz-fuzzer 80924 374026 21079 0 3 0x4000082 thrsleep syz-fuzzer 80924 473075 21079 0 3 0x4000082 thrsleep syz-fuzzer 21079 241682 95534 0 3 0x10008a pause ksh 95534 198072 78728 0 3 0x92 select sshd 62818 343703 1 0 3 0x100083 ttyin getty 78728 121300 1 0 3 0x80 select sshd 33237 167207 79425 74 3 0x100092 bpf pflogd 79425 91549 1 0 3 0x80 netio pflogd 54097 397592 60686 73 3 0x100090 kqread syslogd 60686 9026 1 0 3 0x100082 netio syslogd 24295 323998 1 77 3 0x100090 poll dhclient 39083 314790 1 0 3 0x80 poll dhclient 22509 106228 0 0 3 0x14200 bored smr 26256 216208 0 0 2 0x14200 zerothread 31098 347680 0 0 3 0x14200 aiodoned aiodoned 49419 45411 0 0 3 0x14200 syncer update 51386 499377 0 0 3 0x14200 cleaner cleaner 76285 95235 0 0 3 0x14200 reaper reaper 65893 463463 0 0 3 0x14200 pgdaemon pagedaemon 69621 301624 0 0 3 0x14200 bored crynlk 99604 440252 0 0 3 0x14200 bored crypto 75538 16218 0 0 3 0x40014200 acpi0 acpi0 33517 359372 0 0 3 0x40014200 idle1 39997 58253 0 0 3 0x14200 bored softnet 98622 391259 0 0 3 0x14200 bored systqmp 34966 394385 0 0 3 0x14200 bored systq 71958 308054 0 0 7 0x40014200 softclock 76467 155388 0 0 3 0x40014200 idle0 1 44686 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9500 6408K 6737K 78643K 10752 0 pcb 14 8K 8K 78643K 54 0 rtable 114 4K 4K 78643K 251 0 ifaddr 57 12K 12K 78643K 78 0 counters 43 33K 34K 78643K 51 0 ioctlops 0 0K 4K 78643K 1477 0 iov 0 0K 12K 78643K 11 0 mount 1 1K 1K 78643K 1 0 vnodes 1222 77K 77K 78643K 1297 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 3 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 0K 78643K 31 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 196K 290K 78643K 12766 0 file desc 6 17K 25K 78643K 105 0 sigio 0 0K 0K 78643K 2 0 proc 64 75K 95K 78643K 445 0 subproc 32 2K 2K 78643K 34 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 11 0 in_multi 33 2K 2K 78643K 45 0 ether_multi 1 0K 0K 78643K 6 0 mrt 2 0K 0K 78643K 4 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 67 307K 307K 78643K 67 0 exec 0 0K 1K 78643K 209 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 126 39K 39K 78643K 1292 0 UVM aobj 12 2K 2K 78643K 12 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 2 0K 0K 78643K 28 0 NDP 9 0K 0K 78643K 17 0 temp 82 3016K 3080K 78643K 2732 0 kqueue 3 4K 20K 78643K 19 0 SYN cache 2 16K 16K 78643K 2 0 ddb{1}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle arp 64 6 0 0 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 35 0 33 1 0 1 1 0 8 0 rtentry 112 47 0 2 2 0 2 2 0 8 0 unpcb 120 53 0 39 1 0 1 1 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpqe 32 504 0 504 1 1 0 1 0 8 0 tcpcb 544 58 0 53 1 0 1 1 0 8 0 inpcb 280 207 0 197 2 0 2 2 0 8 1 rttmr 72 2 0 1 1 0 1 1 0 8 0 nd6 48 6 0 0 1 0 1 1 0 8 0 ppxss 1128 1 0 1 1 0 1 1 0 8 1 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 30 0 0 1 0 1 1 0 8 0 pfstkey 112 30 0 0 1 0 1 1 0 8 0 pfstate 328 30 0 0 3 0 3 3 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 256 188 0 0 12 0 12 12 0 8 0 art_table 32 189 0 0 2 0 2 2 0 8 0 art_node 16 46 0 5 1 0 1 1 0 8 0 semupl 112 1 0 1 1 0 1 1 0 8 1 semapl 112 29 0 19 1 0 1 1 0 8 0 shmpl 112 10 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 1573 0 166 46 0 46 46 0 8 0 ffsino 272 1573 0 166 95 0 95 95 0 8 0 nchpl 144 1914 0 294 61 0 61 61 0 8 0 uvmvnodes 72 1648 0 0 30 0 30 30 0 8 0 vnodes 208 1648 0 0 87 0 87 87 0 8 0 namei 1024 5296 0 5296 2 1 1 1 0 8 1 percpumem 16 36 0 4 1 0 1 1 0 8 0 vcpupl 1984 2 0 0 1 0 1 1 0 8 0 vmpool 560 2 0 0 1 0 1 1 0 8 0 scxspl 192 5801 0 5801 8 1 7 7 0 8 7 plimitpl 152 19 0 11 1 0 1 1 0 8 0 sigapl 424 321 0 288 4 0 4 4 0 8 0 futexpl 56 2052 0 2048 1 0 1 1 0 8 0 knotepl 112 106 0 87 2 0 2 2 0 8 1 kqueuepl 144 45 0 43 1 0 1 1 0 8 0 pipelkpl 48 93 0 83 1 0 1 1 0 8 0 pipepl 120 186 0 167 1 0 1 1 0 8 0 fdescpl 496 305 0 288 3 0 3 3 0 8 0 filepl 152 2044 0 1928 7 1 6 6 0 8 1 lockfpl 104 22 0 21 1 0 1 1 0 8 0 lockfspl 48 10 0 9 1 0 1 1 0 8 0 sessionpl 112 18 0 7 1 0 1 1 0 8 0 pgrppl 48 22 0 11 1 0 1 1 0 8 0 ucredpl 96 342 0 332 1 0 1 1 0 8 0 zombiepl 144 288 0 288 2 1 1 1 0 8 1 processpl 960 321 0 288 6 1 5 5 0 8 0 procpl 624 515 0 467 4 0 4 4 0 8 0 sockpl 400 296 0 270 6 1 5 5 0 8 2 mcl64k 65536 3 0 0 1 0 1 1 0 8 0 mcl16k 16384 1 0 0 1 0 1 1 0 8 0 mcl12k 12288 2 0 0 1 0 1 1 0 8 0 mcl9k 9216 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 3 0 0 1 0 1 1 0 8 0 mcl4k 4096 3 0 0 1 0 1 1 0 8 0 mcl2k2 2112 2 0 0 1 0 1 1 0 8 0 mcl2k 2048 241 0 0 30 0 30 30 0 8 0 mtagpl 80 4 0 0 1 0 1 1 0 8 0 mbufpl 256 251 0 0 16 0 16 16 0 8 0 bufpl 280 4284 0 174 294 0 294 294 0 8 0 anonpl 16 44333 0 27228 70 1 69 69 0 124 0 amapchunkpl 152 1582 0 1421 9 0 9 9 0 158 2 amappl16 192 1354 0 429 47 0 47 47 0 8 0 amappl15 184 2 0 0 1 0 1 1 0 8 0 amappl14 176 49 0 44 2 1 1 1 0 8 0 amappl13 168 26 0 25 1 0 1 1 0 8 0 amappl12 160 8 0 6 1 0 1 1 0 8 0 amappl11 152 72 0 54 1 0 1 1 0 8 0 amappl10 144 17 0 13 1 0 1 1 0 8 0 amappl9 136 422 0 417 1 0 1 1 0 8 0 amappl8 128 362 0 333 2 0 2 2 0 8 0 amappl7 120 117 0 106 1 0 1 1 0 8 0 amappl6 112 28 0 22 1 0 1 1 0 8 0 amappl5 104 210 0 194 1 0 1 1 0 8 0 amappl4 96 503 0 470 2 1 1 2 0 8 0 amappl3 88 110 0 105 1 0 1 1 0 8 0 amappl2 80 1517 0 1440 3 1 2 3 0 8 0 amappl1 72 16777 0 16305 26 16 10 20 0 8 0 amappl 80 775 0 721 2 0 2 2 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 11 0 0 1 0 1 1 0 8 0 uaddrrnd 24 307 0 288 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 307 0 288 1 0 1 1 0 8 0 vmmpekpl 168 6409 0 6370 2 0 2 2 0 8 0 vmmpepl 168 44712 0 42509 130 11 119 119 0 357 23 vmsppl 368 306 0 288 2 0 2 2 0 8 0 pdppl 4096 621 0 578 7 1 6 6 0 8 0 pvpl 32 151890 0 131530 169 2 167 167 0 265 2 pmappl 232 306 0 288 2 0 2 2 0 8 0 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 187 0 6 6 0 6 6 0 8 0