panic(ffffffff821eb9b9) at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff82677198) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff82677198) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff82677198,2) at pool_get+0x91 sys/kern/subr_pool.c:572 m_gethdr(2,2) at m_gethdr+0x4c sys/kern/uipc_mbuf.c:283 tcp_output(ffff800000a05980) at tcp_output+0x14e6 tcp_input(ffff800020a4f9e8,ffff800020a4f9f4,6,2) at tcp_input+0x2353 ip_deliver(ffff800020a4f9e8,ffff800020a4f9f4,6,2) at ip_deliver+0x353 sys/netinet/ip_input.c:668 ip_ours(ffff800020a4f9e8,ffff800020a4f9f4,ffff800020a28750,0) at ip_ours+0x412 ip_input_if(ffff800020a4f9e8,ffff800020a4f9f4,4,0,ffff80000017b2a8) at ip_input_if+0x6ce ipv4_input(ffff80000017b2a8,fffffd806d7e4d00) at ipv4_input+0x48 sys/netinet/ip_input.c:215 ether_input(ffff80000017b2a8,fffffd806d7e4d00,0) at ether_input+0x345 sys/net/if_ethersubr.c:461 if_input_process(ffff80000017b2a8,ffff800020a4fb18) at if_input_process+0xfb if_ih_input sys/net/if.c:909 [inline] if_input_process(ffff80000017b2a8,ffff800020a4fb18) at if_input_process+0xfb sys/net/if.c:943 ifiq_process(ffff80000017b6a0) at ifiq_process+0x80 sys/net/ifq.c:646 end trace frame: 0xffff800020a4fbd0, count: 0 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 0xfffffd806a7ee200+16 0x0!=0x36f05c563205d8be ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff821eb9b9) at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff82677198) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff82677198) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff82677198,2) at pool_get+0x91 sys/kern/subr_pool.c:572 m_gethdr(2,2) at m_gethdr+0x4c sys/kern/uipc_mbuf.c:283 tcp_output(ffff800000a05980) at tcp_output+0x14e6 tcp_input(ffff800020a4f9e8,ffff800020a4f9f4,6,2) at tcp_input+0x2353 ip_deliver(ffff800020a4f9e8,ffff800020a4f9f4,6,2) at ip_deliver+0x353 sys/netinet/ip_input.c:668 ip_ours(ffff800020a4f9e8,ffff800020a4f9f4,ffff800020a28750,0) at ip_ours+0x412 ip_input_if(ffff800020a4f9e8,ffff800020a4f9f4,4,0,ffff80000017b2a8) at ip_input_if+0x6ce ipv4_input(ffff80000017b2a8,fffffd806d7e4d00) at ipv4_input+0x48 sys/netinet/ip_input.c:215 ether_input(ffff80000017b2a8,fffffd806d7e4d00,0) at ether_input+0x345 sys/net/if_ethersubr.c:461 if_input_process(ffff80000017b2a8,ffff800020a4fb18) at if_input_process+0xfb if_ih_input sys/net/if.c:909 [inline] if_input_process(ffff80000017b2a8,ffff800020a4fb18) at if_input_process+0xfb sys/net/if.c:943 ifiq_process(ffff80000017b6a0) 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: -15 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff800020a4f2e0 rbx 0xffff800020a4f390 rdx 0xffff800020a28750 rcx 0 rax 0 r8 0xffffffff814a3d9f kprintf+0x16f r9 0x1 r10 0x25 r11 0x19edf67872dd9ae2 r12 0x3000000008 r13 0xffff800020a4f2f0 r14 0x100 r15 0x1 rip 0xffffffff8153b258 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020a4f2d0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (softnet) pid=296317 stat=onproc flags process=14000 proc=200 pri=32, usrpri=51, nice=20 forw=0xffffffffffffffff, list=0xffff800020a284e0,0xffff800020a28eb0 process=0xffff800020a2af00 user=0xffff800020a4a000, vmspace=0xffffffff8263dab0 estcpu=1, cpticks=2, pctcpu=1.35 user=0, sys=2, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 7161 147099 39270 0 2 0 syz-executor.0 7161 488948 39270 0 7 0x4000000 syz-executor.0 92972 477491 12458 0 2 0x82 syz-executor.1 39270 519087 12458 0 2 0x482 syz-executor.0 12458 143470 76430 0 2 0x82 syz-fuzzer 12458 429311 76430 0 2 0x4000482 syz-fuzzer 12458 472973 76430 0 3 0x4000082 thrsleep syz-fuzzer 12458 361636 76430 0 3 0x4000082 thrsleep syz-fuzzer 12458 279000 76430 0 3 0x4000082 thrsleep syz-fuzzer 12458 236804 76430 0 3 0x4000082 thrsleep syz-fuzzer 12458 341226 76430 0 3 0x4000082 thrsleep syz-fuzzer 12458 141099 76430 0 3 0x4000082 thrsleep syz-fuzzer 12458 154164 76430 0 2 0x4000082 syz-fuzzer 12458 431559 76430 0 3 0x4000082 thrsleep syz-fuzzer 76430 405734 53536 0 3 0x10008a pause ksh 53536 470246 90182 0 2 0x12 sshd 89438 242250 1 0 3 0x100083 ttyin getty 90182 208682 1 0 3 0x80 select sshd 55332 484816 28892 74 3 0x100092 bpf pflogd 28892 285298 1 0 3 0x80 netio pflogd 20261 333876 22179 73 3 0x100090 kqread syslogd 22179 453795 1 0 3 0x100082 netio syslogd 45194 209025 1 77 3 0x100090 poll dhclient 91494 512844 1 0 3 0x80 poll dhclient 37683 153967 0 0 2 0x14200 zerothread 55147 271400 0 0 3 0x14200 aiodoned aiodoned 16473 358736 0 0 2 0x14200 update 70823 518749 0 0 3 0x14200 cleaner cleaner 43235 516885 0 0 3 0x14200 reaper reaper 16499 274409 0 0 3 0x14200 pgdaemon pagedaemon 24360 268713 0 0 3 0x14200 bored crynlk 23797 371099 0 0 3 0x14200 bored crypto 21842 249026 0 0 3 0x40014200 acpi0 acpi0 55905 11439 0 0 3 0x40014200 idle1 *98251 296317 0 0 7 0x14200 softnet 7981 509291 0 0 3 0x14200 bored systqmp 63724 252599 0 0 3 0x14200 bored systq 64314 52363 0 0 2 0x40014200 softclock 77662 502468 0 0 3 0x40014200 idle0 22088 281656 0 0 3 0x14200 bored smr 1 351772 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 12458 (syz-fuzzer) thread 0xffff800020a7c9c8 (141099) shared rwlock vmmaplk r = 0 (0xfffffd806e9aa190) #0 witness_lock+0x52e sys/kern/subr_witness.c:1164 #1 uvm_map_inentry_fix+0xa3 vm_map_lock_read_ln sys/uvm/uvm_map.c:5431 [inline] #1 uvm_map_inentry_fix+0xa3 sys/uvm/uvm_map.c:1857 #2 uvm_map_inentry+0xd2 sys/uvm/uvm_map.c:1889 #3 syscall+0x397 mi_syscall sys/sys/syscall_mi.h:81 [inline] #3 syscall+0x397 sys/arch/amd64/amd64/trap.c:570 #4 Xsyscall+0x128 exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82662d80) #0 witness_lock+0x52e sys/kern/subr_witness.c:1164 #1 uvm_map_inentry+0xbe sys/uvm/uvm_map.c:1889 #2 syscall+0x397 mi_syscall sys/sys/syscall_mi.h:81 [inline] #2 syscall+0x397 sys/arch/amd64/amd64/trap.c:570 #3 Xsyscall+0x128 Process 98251 (softnet) thread 0xffff800020a28750 (296317) shared rwlock netlock r = 0 (0xffffffff825135f8) #0 witness_lock+0x52e sys/kern/subr_witness.c:1164 #1 if_input_process+0x84 sys/net/if.c:941 #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+0x52e sys/kern/subr_witness.c:1164 #1 taskq_thread+0x8f sys/kern/kern_task.c:368 #2 proc_trampoline+0x1c ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9506 6607K 7045K 78643K 10665 0 pcb 13 8K 8K 78643K 27 0 rtable 107 3K 3K 78643K 205 0 ifaddr 53 11K 11K 78643K 57 0 counters 43 33K 33K 78643K 43 0 ioctlops 0 0K 4K 78643K 1469 0 iov 0 0K 16K 78643K 7 0 mount 1 1K 1K 78643K 1 0 vnodes 1224 77K 77K 78643K 1244 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 5 13K 25K 78643K 54 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 ip_moptions 0 0K 0K 78643K 6 0 in_multi 33 2K 2K 78643K 42 0 ether_multi 1 0K 0K 78643K 4 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 31 148K 148K 78643K 31 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 110 22K 22K 78643K 1078 0 UVM aobj 2 2K 2K 78643K 2 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 14 0 NDP 12 0K 0K 78643K 12 0 temp 75 3012K 3076K 78643K 2303 0 kqueue 3 4K 4K 78643K 3 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 19 0 17 1 0 1 1 0 8 0 rtentry 112 46 0 1 2 0 2 2 0 8 0 unpcb 120 35 0 25 1 0 1 1 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpqe 32 173 0 173 1 0 1 1 0 8 1 tcpcb 544 26 0 22 1 0 1 1 0 8 0 inpcb 280 75 0 68 1 0 1 1 0 8 0 nd6 48 7 0 0 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 18 0 0 1 0 1 1 0 8 0 pfstkey 112 18 0 0 1 0 1 1 0 8 0 pfstate 328 18 0 0 2 0 2 2 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 256 190 0 0 12 0 12 12 0 8 0 art_table 32 191 0 0 2 0 2 2 0 8 0 art_node 16 45 0 4 1 0 1 1 0 8 0 semupl 112 1 0 1 1 0 1 1 0 8 1 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 1455 0 48 46 0 46 46 0 8 0 ffsino 272 1455 0 48 94 0 94 94 0 8 0 nchpl 144 1713 0 98 61 0 61 61 0 8 0 uvmvnodes 72 1517 0 0 28 0 28 28 0 8 0 vnodes 208 1517 0 0 80 0 80 80 0 8 0 namei 1024 4384 0 4384 1 0 1 1 0 8 1 percpumem 16 32 0 0 1 0 1 1 0 8 0 scxspl 192 4929 0 4929 2 1 1 2 0 8 1 plimitpl 152 16 0 8 1 0 1 1 0 8 0 sigapl 424 269 0 238 4 0 4 4 0 8 0 futexpl 56 466 0 466 1 0 1 1 0 8 1 knotepl 112 53 0 34 1 0 1 1 0 8 0 kqueuepl 144 6 0 4 1 0 1 1 0 8 0 pipelkpl 48 86 0 76 1 0 1 1 0 8 0 pipepl 120 172 0 153 2 0 2 2 0 8 1 fdescpl 496 254 0 238 3 0 3 3 0 8 0 filepl 152 1296 0 1196 5 0 5 5 0 8 1 lockfpl 104 12 0 11 1 0 1 1 0 8 0 lockfspl 48 5 0 4 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 57 0 48 1 0 1 1 0 8 0 zombiepl 144 238 0 238 1 0 1 1 0 8 1 processpl 960 269 0 238 5 0 5 5 0 8 0 procpl 624 323 0 282 4 0 4 4 0 8 0 sockpl 400 129 0 110 3 0 3 3 0 8 1 mcl64k 65536 7 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 mcl4k 4096 4 0 0 1 0 1 1 0 8 0 mcl2k 2048 190 0 0 23 0 23 23 0 8 0 mtagpl 80 4 0 0 1 0 1 1 0 8 0 mbufpl 256 203 0 0 13 0 13 13 0 8 0 bufpl 280 4082 0 174 280 0 280 280 0 8 0 anonpl 16 39421 0 23721 65 1 64 64 0 124 0 amapchunkpl 152 1157 0 1021 8 0 8 8 0 158 1 amappl16 192 1048 0 192 43 0 43 43 0 8 0 amappl15 184 1 0 0 1 0 1 1 0 8 0 amappl14 176 4 0 3 2 1 1 1 0 8 0 amappl13 168 34 0 31 1 0 1 1 0 8 0 amappl12 160 19 0 14 2 1 1 1 0 8 0 amappl11 152 82 0 62 2 0 2 2 0 8 1 amappl10 144 30 0 24 1 0 1 1 0 8 0 amappl9 136 392 0 388 1 0 1 1 0 8 0 amappl8 128 313 0 290 1 0 1 1 0 8 0 amappl7 120 127 0 117 1 0 1 1 0 8 0 amappl6 112 27 0 23 1 0 1 1 0 8 0 amappl5 104 163 0 146 1 0 1 1 0 8 0 amappl4 96 508 0 472 2 0 2 2 0 8 1 amappl3 88 105 0 100 1 0 1 1 0 8 0 amappl2 80 1110 0 1039 3 0 3 3 0 8 1 amappl1 72 15968 0 15531 26 8 18 20 0 8 7 amappl 80 570 0 526 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 24 254 0 238 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 254 0 238 1 0 1 1 0 8 0 vmmpekpl 168 6003 0 5971 2 0 2 2 0 8 0 vmmpepl 168 38346 0 36346 125 4 121 121 0 357 33 vmsppl 368 253 0 238 2 0 2 2 0 8 0 pdppl 4096 515 0 476 6 0 6 6 0 8 0 pvpl 32 136247 0 117451 155 0 155 155 0 265 2 pmappl 232 253 0 238 2 0 2 2 0 8 1 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 170 0 3 5 0 5 5 0 8 0