panic(ffffffff821c9867) at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff82659458) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1789 [inline] pool_cache_get(ffffffff82659458) at pool_cache_get+0x323 sys/kern/subr_pool.c:1892 pool_get(ffffffff82659458,1) 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(ffff800020ab71a8,0,1000,ffff800020ab7270) at m_getuio+0xe4 sys/kern/uipc_socket.c:556 sosend(fffffd806f65e600,0,ffff800020ab7270,0,0,80) at sosend+0x54e sys/kern/uipc_socket.c:511 sendit(ffff800020a773c8,5,ffff800020ab73d0,0,ffff800020ab74c0) at sendit+0x52b sys/kern/uipc_syscalls.c:662 sys_sendmsg(ffff800020a773c8,ffff800020ab7470,ffff800020ab74c0) at sys_sendmsg+0x1a4 sys/kern/uipc_syscalls.c:567 syscall(ffff800020ab7540) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800020ab7540) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffd2b80, 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{0}> ddb{0}> set $lines = 0 ddb{0}> set $maxwidth = 0 ddb{0}> show panic pool_cache_item_magic_check: mbufpl cpu free list modified: item addr 0xfffffd8068eefd00+16 0x0!=0x9a6bdc8274612c58 ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff821c9867) at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff82659458) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1789 [inline] pool_cache_get(ffffffff82659458) at pool_cache_get+0x323 sys/kern/subr_pool.c:1892 pool_get(ffffffff82659458,1) 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(ffff800020ab71a8,0,1000,ffff800020ab7270) at m_getuio+0xe4 sys/kern/uipc_socket.c:556 sosend(fffffd806f65e600,0,ffff800020ab7270,0,0,80) at sosend+0x54e sys/kern/uipc_socket.c:511 sendit(ffff800020a773c8,5,ffff800020ab73d0,0,ffff800020ab74c0) at sendit+0x52b sys/kern/uipc_syscalls.c:662 sys_sendmsg(ffff800020a773c8,ffff800020ab7470,ffff800020ab74c0) at sys_sendmsg+0x1a4 sys/kern/uipc_syscalls.c:567 syscall(ffff800020ab7540) at syscall+0x4a4 mi_syscall sys/sys/syscall_mi.h:92 [inline] syscall(ffff800020ab7540) at syscall+0x4a4 sys/arch/amd64/amd64/trap.c:555 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffd2b80, count: -11 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff800020ab6ed0 rbx 0xffff800020ab6f80 rdx 0xffff800020a773c8 rcx 0 rax 0 r8 0xffffffff8210daff kprintf+0x16f r9 0x1 r10 0x25 r11 0x7a8ffef184797ce5 r12 0x3000000008 r13 0xffff800020ab6ee0 r14 0x100 r15 0x1 rip 0xffffffff81aa27c8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020ab6ec0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (dhclient) pid=247320 stat=onproc flags process=100010 proc=0 pri=50, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff800020a77150,0xffff800020ad8c78 process=0xffff800020aa2720 user=0xffff800020ab2000, vmspace=0xfffffd807efff000 estcpu=0, cpticks=2, pctcpu=0.0 user=0, sys=2, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 19079 379441 36457 0 3 0x82 piperd syz-executor.1 86988 94319 36457 0 3 0x82 nanosleep syz-executor.0 36457 394940 97824 0 3 0x82 thrsleep syz-fuzzer 36457 524267 97824 0 3 0x4000082 thrsleep syz-fuzzer 36457 64311 97824 0 3 0x4000082 thrsleep syz-fuzzer 36457 304371 97824 0 3 0x4000082 thrsleep syz-fuzzer 36457 13845 97824 0 3 0x4000082 thrsleep syz-fuzzer 36457 2564 97824 0 3 0x4000082 thrsleep syz-fuzzer 36457 389048 97824 0 3 0x4000082 thrsleep syz-fuzzer 36457 202046 97824 0 3 0x4000082 thrsleep syz-fuzzer 36457 378686 97824 0 3 0x4000082 thrsleep syz-fuzzer 36457 161394 97824 0 3 0x4000082 kqread syz-fuzzer 97824 161971 41148 0 3 0x10008a pause ksh 41148 285785 97218 0 3 0x92 select sshd 89036 324435 1 0 3 0x100083 ttyin getty 97218 442793 1 0 3 0x80 select sshd 85048 62921 37678 74 3 0x100092 bpf pflogd 37678 206009 1 0 3 0x80 netio pflogd 92578 307286 7012 73 3 0x100090 kqread syslogd 7012 129649 1 0 3 0x100082 netio syslogd *21318 247320 1 77 7 0x100010 dhclient 61258 20850 1 0 3 0x80 poll dhclient 24512 123246 0 0 3 0x14200 pgzero zerothread 21900 51292 0 0 3 0x14200 aiodoned aiodoned 25006 304602 0 0 3 0x14200 syncer update 94149 408428 0 0 3 0x14200 cleaner cleaner 20693 160831 0 0 7 0x14200 reaper 61261 71314 0 0 3 0x14200 pgdaemon pagedaemon 60444 159787 0 0 3 0x14200 bored crynlk 78918 175991 0 0 3 0x14200 bored crypto 51928 67890 0 0 3 0x40014200 acpi0 acpi0 90400 235999 0 0 3 0x40014200 idle1 25718 319396 0 0 3 0x14200 bored softnet 4959 212482 0 0 3 0x14200 bored systqmp 42863 48172 0 0 3 0x14200 bored systq 92132 484558 0 0 3 0x40014200 bored softclock 3764 415871 0 0 3 0x40014200 idle0 53966 310478 0 0 3 0x14200 bored smr 1 477234 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 20693 (reaper) thread 0xffff800020a778b8 (160831) exclusive rwlock kmmaplk r = 0 (0xffffffff82543e38) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 rw_enter+0x453 sys/kern/kern_rwlock.c:309 #2 vm_map_lock_ln+0x10d sys/uvm/uvm_map.c:5409 #3 uvm_unmap+0x6b sys/uvm/uvm_map.c:2039 #4 uvm_uarea_free+0x36 sys/uvm/uvm_glue.c:287 #5 reaper+0x156 sys/kern/kern_exit.c:432 #6 proc_trampoline+0x1c exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82652ea8) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 reaper+0x14e sys/kern/kern_exit.c:431 #2 proc_trampoline+0x1c ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9469 6398K 6400K 78643K 10563 0 pcb 13 8K 8K 78643K 21 0 rtable 108 4K 4K 78643K 210 0 ifaddr 44 10K 11K 78643K 52 0 counters 39 33K 33K 78643K 39 0 ioctlops 0 0K 4K 78643K 1469 0 mount 1 1K 1K 78643K 1 0 vnodes 1215 76K 76K 78643K 1222 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 6 0K 0K 78643K 6 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 196K 290K 78643K 12766 0 file desc 4 9K 25K 78643K 41 0 proc 59 63K 83K 78643K 438 0 subproc 32 2K 2K 78643K 34 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 in_multi 33 2K 2K 78643K 33 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 18 79K 79K 78643K 18 0 exec 0 0K 1K 78643K 207 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 121 22K 22K 78643K 1068 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 6 0K 0K 78643K 11 0 temp 80 3026K 3090K 78643K 3491 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 6 0 0 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 80 19 0 17 1 0 1 1 0 8 0 rtentry 112 45 0 1 2 0 2 2 0 8 0 unpcb 120 27 0 17 1 0 1 1 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpqe 32 65 0 65 1 0 1 1 0 8 1 tcpcb 544 10 0 6 1 0 1 1 0 8 0 inpcb 280 51 0 44 1 0 1 1 0 8 0 nd6 48 4 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 11 0 0 1 0 1 1 0 8 0 pfstkey 112 11 0 0 1 0 1 1 0 8 0 pfstate 328 11 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 256 212 0 0 14 0 14 14 0 8 0 art_table 32 213 0 0 2 0 2 2 0 8 0 art_node 16 44 0 4 1 0 1 1 0 8 0 sysvmsgpl 40 8 0 6 1 0 1 1 0 8 0 semapl 112 4 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 1439 0 30 46 0 46 46 0 8 0 ffsino 272 1439 0 30 95 0 95 95 0 8 0 nchpl 144 1678 0 60 61 0 61 61 0 8 0 uvmvnodes 72 1483 0 0 27 0 27 27 0 8 0 vnodes 208 1483 0 0 79 0 79 79 0 8 0 namei 1024 4296 0 4296 1 0 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 scxspl 192 4507 0 4507 3 2 1 2 0 8 1 plimitpl 152 15 0 7 1 0 1 1 0 8 0 sigapl 432 240 0 226 3 0 3 3 0 8 1 futexpl 56 185 0 185 1 0 1 1 0 8 1 knotepl 112 53 0 34 1 0 1 1 0 8 0 kqueuepl 104 2 0 0 1 0 1 1 0 8 0 pipepl 160 156 0 137 2 0 2 2 0 8 1 fdescpl 488 241 0 226 3 0 3 3 0 8 0 filepl 152 1218 0 1118 5 0 5 5 0 8 1 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 7 1 0 1 1 0 8 0 pgrppl 48 18 0 7 1 0 1 1 0 8 0 ucredpl 96 45 0 36 1 0 1 1 0 8 0 zombiepl 144 226 0 225 1 0 1 1 0 8 0 processpl 904 256 0 225 4 0 4 4 0 8 0 procpl 632 291 0 251 5 0 5 5 0 8 1 sockpl 384 97 0 78 4 1 3 3 0 8 1 mcl12k 12288 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 1 0 0 1 0 1 1 0 8 0 mcl4k 4096 2 0 0 1 0 1 1 0 8 0 mcl2k 2048 292 0 0 36 0 36 36 0 8 0 mtagpl 80 1 0 0 1 0 1 1 0 8 0 mbufpl 256 300 0 0 18 0 18 18 0 8 0 bufpl 280 6268 0 1340 352 0 352 352 0 8 0 anonpl 16 39610 0 22789 69 1 68 68 0 125 0 amapchunkpl 152 1095 0 941 8 0 8 8 0 158 1 amappl16 192 1006 0 93 46 0 46 46 0 8 0 amappl15 184 71 0 64 1 0 1 1 0 8 0 amappl14 176 27 0 25 1 0 1 1 0 8 0 amappl12 160 15 0 11 1 0 1 1 0 8 0 amappl11 152 53 0 38 1 0 1 1 0 8 0 amappl10 144 11 0 8 1 0 1 1 0 8 0 amappl9 136 591 0 588 1 0 1 1 0 8 0 amappl8 128 125 0 102 1 0 1 1 0 8 0 amappl7 120 111 0 99 1 0 1 1 0 8 0 amappl6 112 61 0 54 1 0 1 1 0 8 0 amappl5 104 147 0 134 1 0 1 1 0 8 0 amappl4 96 488 0 458 1 0 1 1 0 8 0 amappl3 88 117 0 107 1 0 1 1 0 8 0 amappl2 80 1022 0 945 3 1 2 3 0 8 0 amappl1 72 15127 0 14661 27 12 15 21 0 8 5 amappl 80 545 0 494 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 1 0 0 1 0 1 1 0 8 0 uaddrrnd 24 241 0 225 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 241 0 225 1 0 1 1 0 8 0 vmmpekpl 168 5817 0 5786 2 0 2 2 0 8 0 vmmpepl 168 37353 0 35240 138 10 128 128 0 357 34 vmsppl 368 240 0 225 2 0 2 2 0 8 0 pdppl 4096 489 0 450 7 1 6 6 0 8 0 pvpl 32 132389 0 112420 165 0 165 165 0 265 3 pmappl 232 240 0 225 2 0 2 2 0 8 1 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 188 0 4 6 0 6 6 0 8 0