panic(ffffffff821f1d48) at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff82685c78) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff82685c78) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff82685c78,2) 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(ffff800000a0b540) at tcp_output+0x14e6 tcp_input(ffff800020e38dd8,ffff800020e38de4,6,2) at tcp_input+0x2353 ip_deliver(ffff800020e38dd8,ffff800020e38de4,6,2) at ip_deliver+0x353 sys/netinet/ip_input.c:668 ip_ours(ffff800020e38dd8,ffff800020e38de4,ffff800020e18750,0) at ip_ours+0x412 ip_input_if(ffff800020e38dd8,ffff800020e38de4,4,0,ffff80000017b2a8) at ip_input_if+0x6ce ipv4_input(ffff80000017b2a8,fffffd806f2d5800) at ipv4_input+0x48 sys/netinet/ip_input.c:215 ether_input(ffff80000017b2a8,fffffd806f2d5800,0) at ether_input+0x345 sys/net/if_ethersubr.c:461 if_input_process(ffff80000017b2a8,ffff800020e38f08) at if_input_process+0xfb if_ih_input sys/net/if.c:909 [inline] if_input_process(ffff80000017b2a8,ffff800020e38f08) 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: 0xffff800020e38fc0, 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 0xfffffd8069464c00+16 0x0!=0xbbbdd6901be8208d ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff821f1d48) at panic+0x15c sys/kern/subr_prf.c:207 pool_cache_get(ffffffff82685c78) at pool_cache_get+0x323 pool_cache_item_magic_check sys/kern/subr_pool.c:1781 [inline] pool_cache_get(ffffffff82685c78) at pool_cache_get+0x323 sys/kern/subr_pool.c:1884 pool_get(ffffffff82685c78,2) 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(ffff800000a0b540) at tcp_output+0x14e6 tcp_input(ffff800020e38dd8,ffff800020e38de4,6,2) at tcp_input+0x2353 ip_deliver(ffff800020e38dd8,ffff800020e38de4,6,2) at ip_deliver+0x353 sys/netinet/ip_input.c:668 ip_ours(ffff800020e38dd8,ffff800020e38de4,ffff800020e18750,0) at ip_ours+0x412 ip_input_if(ffff800020e38dd8,ffff800020e38de4,4,0,ffff80000017b2a8) at ip_input_if+0x6ce ipv4_input(ffff80000017b2a8,fffffd806f2d5800) at ipv4_input+0x48 sys/netinet/ip_input.c:215 ether_input(ffff80000017b2a8,fffffd806f2d5800,0) at ether_input+0x345 sys/net/if_ethersubr.c:461 if_input_process(ffff80000017b2a8,ffff800020e38f08) at if_input_process+0xfb if_ih_input sys/net/if.c:909 [inline] if_input_process(ffff80000017b2a8,ffff800020e38f08) 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 0xffff800020e386d0 rbx 0xffff800020e38780 rdx 0xffff800020e18750 rcx 0 rax 0 r8 0xffffffff81fa1f9f kprintf+0x16f r9 0x1 r10 0x25 r11 0x3593d0d8bc06473b r12 0x3000000008 r13 0xffff800020e386e0 r14 0x100 r15 0x1 rip 0xffffffff813caa28 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020e386c0 ss 0 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (softnet) pid=507251 stat=onproc flags process=14000 proc=200 pri=32, usrpri=54, nice=20 forw=0xffffffffffffffff, list=0xffff800020e184e0,0xffff800020e189d0 process=0xffff800020e1ab88 user=0xffff800020e34000, vmspace=0xffffffff8265e070 estcpu=4, cpticks=15, pctcpu=1.3 user=0, sys=15, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 64806 138382 25646 0 2 0 syz-executor.1 64806 58112 25646 0 2 0x4000480 syz-executor.1 64806 470238 25646 0 3 0x4000080 bell syz-executor.1 25646 283250 92380 0 2 0x482 syz-executor.1 35253 410450 92380 0 2 0x2 syz-executor.0 92380 23611 44974 0 3 0x82 thrsleep syz-fuzzer 92380 48556 44974 0 2 0x4000482 syz-fuzzer 92380 127037 44974 0 3 0x4000082 thrsleep syz-fuzzer 92380 36292 44974 0 3 0x4000082 thrsleep syz-fuzzer 92380 272442 44974 0 3 0x4000082 thrsleep syz-fuzzer 92380 210434 44974 0 3 0x4000082 thrsleep syz-fuzzer 92380 489416 44974 0 3 0x4000082 thrsleep syz-fuzzer 92380 491258 44974 0 3 0x4000082 thrsleep syz-fuzzer 92380 38238 44974 0 2 0x4000482 syz-fuzzer 92380 364830 44974 0 3 0x4000082 thrsleep syz-fuzzer 92380 454766 44974 0 3 0x4000082 kqread syz-fuzzer 44974 340089 84868 0 3 0x10008a pause ksh 84868 347723 22411 0 7 0x52 sshd 48150 405693 1 0 3 0x100083 ttyin getty 22411 71278 1 0 3 0x80 select sshd 50921 397305 84507 74 3 0x100092 bpf pflogd 84507 411259 1 0 3 0x80 netio pflogd 66474 452737 49792 73 3 0x100090 kqread syslogd 49792 91151 1 0 3 0x100082 netio syslogd 99023 358376 1 77 3 0x100090 poll dhclient 48695 292673 1 0 3 0x80 poll dhclient 40203 82117 0 0 3 0x14200 bored smr 67325 182072 0 0 2 0x14200 zerothread 75830 467622 0 0 3 0x14200 aiodoned aiodoned 55777 241361 0 0 3 0x14200 syncer update 95151 458671 0 0 3 0x14200 cleaner cleaner 38437 49071 0 0 3 0x14200 reaper reaper 11124 101949 0 0 3 0x14200 pgdaemon pagedaemon 88043 342970 0 0 3 0x14200 bored crynlk 83203 492302 0 0 3 0x14200 bored crypto 39601 27158 0 0 3 0x40014200 acpi0 acpi0 62518 85321 0 0 3 0x40014200 idle1 *46753 507251 0 0 7 0x14200 softnet 23278 390999 0 0 3 0x14200 bored systqmp 10331 3975 0 0 3 0x14200 bored systq 45716 244832 0 0 3 0x40014200 bored softclock 7330 264367 0 0 3 0x40014200 idle0 1 85756 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 46753 (softnet) thread 0xffff800020e18750 (507251) shared rwlock netlock r = 0 (0xffffffff824c4bc8) #0 witness_lock+0x4c5 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+0x4c5 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 9489 6404K 6670K 78643K 10735 0 pcb 13 8K 8K 78643K 71 0 rtable 108 4K 4K 78643K 219 0 ifaddr 55 12K 12K 78643K 71 0 counters 43 33K 34K 78643K 47 0 ioctlops 0 0K 4K 78643K 1472 0 iov 0 0K 28K 78643K 24 0 mount 1 1K 1K 78643K 1 0 vnodes 1222 77K 77K 78643K 1277 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 4 0K 0K 78643K 8 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 196K 290K 78643K 12766 0 file desc 5 13K 25K 78643K 91 0 proc 61 63K 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 17 0 in_multi 40 2K 2K 78643K 58 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 37 175K 175K 78643K 37 0 exec 0 0K 1K 78643K 219 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 103 37K 39K 78643K 1194 0 UVM aobj 8 2K 2K 78643K 8 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 12 0 NDP 8 0K 0K 78643K 14 0 temp 76 3036K 3100K 78643K 2753 0 kqueue 3 4K 8K 78643K 9 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 21 0 19 1 0 1 1 0 8 0 rtentry 112 45 0 1 2 0 2 2 0 8 0 unpcb 120 37 0 27 1 0 1 1 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpqe 32 148 0 148 1 0 1 1 0 8 1 tcpcb 544 60 0 56 1 0 1 1 0 8 0 inpcb 280 161 0 154 2 0 2 2 0 8 1 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 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 256 189 0 0 12 0 12 12 0 8 0 art_table 32 190 0 0 2 0 2 2 0 8 0 art_node 16 44 0 4 1 0 1 1 0 8 0 semupl 112 1 0 1 1 0 1 1 0 8 1 semapl 112 2 0 0 1 0 1 1 0 8 0 shmpl 112 6 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 1518 0 111 46 0 46 46 0 8 0 ffsino 272 1518 0 111 94 0 94 94 0 8 0 nchpl 144 1816 0 199 61 0 61 61 0 8 0 uvmvnodes 72 1601 0 0 30 0 30 30 0 8 0 vnodes 208 1601 0 0 85 0 85 85 0 8 0 namei 1024 4686 0 4686 1 0 1 1 0 8 1 percpumem 16 34 0 2 1 0 1 1 0 8 0 vcpupl 1984 1 0 0 1 0 1 1 0 8 0 vmpool 560 3 0 2 1 0 1 1 0 8 0 scxspl 192 5228 0 5228 2 1 1 2 0 8 1 plimitpl 152 17 0 9 1 0 1 1 0 8 0 sigapl 424 306 0 275 4 0 4 4 0 8 0 futexpl 56 1011 0 1011 1 0 1 1 0 8 1 knotepl 112 61 0 42 1 0 1 1 0 8 0 kqueuepl 144 10 0 8 1 0 1 1 0 8 0 pipelkpl 48 74 0 64 1 0 1 1 0 8 0 pipepl 120 148 0 129 1 0 1 1 0 8 0 fdescpl 496 291 0 275 3 0 3 3 0 8 0 filepl 152 1476 0 1374 5 0 5 5 0 8 1 lockfpl 104 34 0 33 1 0 1 1 0 8 0 lockfspl 48 11 0 10 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 65 0 56 1 0 1 1 0 8 0 zombiepl 144 275 0 275 1 0 1 1 0 8 1 processpl 984 306 0 275 5 0 5 5 0 8 1 procpl 624 440 0 397 4 0 4 4 0 8 0 sockpl 400 219 0 200 3 0 3 3 0 8 1 mcl64k 65536 6 0 0 1 0 1 1 0 8 0 mcl12k 12288 1 0 0 1 0 1 1 0 8 0 mcl9k 9216 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 2 0 0 1 0 1 1 0 8 0 mcl4k 4096 6 0 0 1 0 1 1 0 8 0 mcl2k 2048 217 0 0 27 0 27 27 0 8 0 mtagpl 80 16 0 0 1 0 1 1 0 8 0 mbufpl 256 229 0 0 14 0 14 14 0 8 0 bufpl 280 4127 0 174 283 0 283 283 0 8 0 anonpl 16 45294 0 31534 69 1 68 68 0 124 12 amapchunkpl 152 1419 0 1285 9 0 9 9 0 158 3 amappl16 192 1356 0 613 45 1 44 45 0 8 6 amappl15 184 33 0 31 1 0 1 1 0 8 0 amappl14 176 2 0 1 2 1 1 1 0 8 0 amappl13 168 27 0 26 1 0 1 1 0 8 0 amappl12 160 32 0 29 1 0 1 1 0 8 0 amappl11 152 80 0 60 2 0 2 2 0 8 1 amappl10 144 16 0 13 1 0 1 1 0 8 0 amappl9 136 386 0 383 1 0 1 1 0 8 0 amappl8 128 309 0 292 1 0 1 1 0 8 0 amappl7 120 116 0 105 1 0 1 1 0 8 0 amappl6 112 24 0 18 1 0 1 1 0 8 0 amappl5 104 232 0 214 1 0 1 1 0 8 0 amappl4 96 502 0 469 2 1 1 2 0 8 0 amappl3 88 109 0 102 1 0 1 1 0 8 0 amappl2 80 1363 0 1293 3 1 2 3 0 8 0 amappl1 72 16491 0 16050 25 11 14 20 0 8 4 amappl 80 685 0 641 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 7 0 0 1 0 1 1 0 8 0 uaddrrnd 24 294 0 277 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 294 0 277 1 0 1 1 0 8 0 vmmpekpl 168 6048 0 6012 2 0 2 2 0 8 0 vmmpepl 168 42642 0 40764 101 2 99 99 0 357 12 vmsppl 368 293 0 277 2 0 2 2 0 8 0 pdppl 4096 596 0 555 6 0 6 6 0 8 0 pvpl 32 148160 0 131264 165 0 165 165 0 265 27 pmappl 232 293 0 277 2 0 2 2 0 8 1 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 175 0 3 5 0 5 5 0 8 0