panic: pool_p_free: anonpl free list modified: page 0xfffffd806307a000; item addr 0xfffffd806307a010; offset 0x0=0x0 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 185734 5028 0 0 0x480 0 syz-executor.1 *149655 45457 0 0x14000 0x200 1 systqmp db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff82226469) at panic+0x15c sys/kern/subr_prf.c:207 pool_p_free(ffffffff82645fe8,fffffd806307af90) at pool_p_free+0x1de sys/kern/subr_pool.c:991 pool_gc_pages(0) at pool_gc_pages+0x255 sys/kern/subr_pool.c:1586 taskq_thread(ffffffff82486350) at taskq_thread+0x9c sys/kern/kern_task.c:369 end trace frame: 0x0, count: 10 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_p_free: anonpl free list modified: page 0xfffffd806307a000; item addr 0xfffffd806307a010; offset 0x0=0x0 ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff82226469) at panic+0x15c sys/kern/subr_prf.c:207 pool_p_free(ffffffff82645fe8,fffffd806307af90) at pool_p_free+0x1de sys/kern/subr_pool.c:991 pool_gc_pages(0) at pool_gc_pages+0x255 sys/kern/subr_pool.c:1586 taskq_thread(ffffffff82486350) at taskq_thread+0x9c sys/kern/kern_task.c:369 end trace frame: 0x0, count: -5 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff800020a49430 rbx 0xffff800020a494e0 rdx 0xffff800020a28000 rcx 0 rax 0 r8 0xffffffff81d817ff kprintf+0x16f r9 0x1 r10 0x25 r11 0xc468c33f3fd89419 r12 0x3000000008 r13 0xffff800020a49440 r14 0x100 r15 0x1 rip 0xffffffff81172258 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020a49420 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (systqmp) pid=149655 stat=onproc flags process=14000 proc=200 pri=32, usrpri=51, nice=20 forw=0xffffffffffffffff, list=0xffff800020a28278,0xffff800020a289f0 process=0xffff800020a2a700 user=0xffff800020a44000, vmspace=0xffffffff826393a8 estcpu=1, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 5028 185734 90164 0 7 0x480 syz-executor.1 5028 308506 90164 0 3 0x4000080 ttyout syz-executor.1 5028 521437 90164 0 3 0x4000080 fsleep syz-executor.1 66276 426098 0 0 3 0x14200 bored sosplice 90164 58678 12947 0 3 0x82 nanosleep syz-executor.1 20445 424487 12947 0 3 0x82 piperd syz-executor.0 12947 485691 73134 0 3 0x82 thrsleep syz-fuzzer 12947 286266 73134 0 3 0x4000082 thrsleep syz-fuzzer 12947 285498 73134 0 3 0x4000082 thrsleep syz-fuzzer 12947 439126 73134 0 3 0x4000082 thrsleep syz-fuzzer 12947 144935 73134 0 3 0x4000082 thrsleep syz-fuzzer 12947 369960 73134 0 3 0x4000082 kqread syz-fuzzer 12947 395973 73134 0 3 0x4000082 thrsleep syz-fuzzer 12947 178984 73134 0 3 0x4000082 thrsleep syz-fuzzer 12947 346288 73134 0 3 0x4000082 thrsleep syz-fuzzer 12947 280352 73134 0 3 0x4000082 thrsleep syz-fuzzer 73134 516262 98041 0 3 0x10008a pause ksh 98041 302905 7238 0 3 0x92 select sshd 2945 379497 1 0 3 0x100083 ttyin getty 7238 12552 1 0 3 0x80 select sshd 5517 410108 79527 74 3 0x100092 bpf pflogd 79527 294653 1 0 3 0x80 netio pflogd 76953 168839 81671 73 3 0x100090 kqread syslogd 81671 232216 1 0 3 0x100082 netio syslogd 70838 473857 1 77 3 0x100090 poll dhclient 41015 492367 1 0 3 0x80 poll dhclient 29012 104268 0 0 3 0x14200 pgzero zerothread 65625 62578 0 0 3 0x14200 aiodoned aiodoned 24154 248657 0 0 3 0x14200 syncer update 37752 409346 0 0 3 0x14200 cleaner cleaner 3973 3075 0 0 3 0x14200 reaper reaper 81057 117467 0 0 3 0x14200 pgdaemon pagedaemon 12385 164892 0 0 3 0x14200 bored crynlk 30157 392014 0 0 3 0x14200 bored crypto 20911 364969 0 0 3 0x40014200 acpi0 acpi0 27075 409345 0 0 3 0x40014200 idle1 85474 171272 0 0 3 0x14200 bored softnet *45457 149655 0 0 7 0x14200 systqmp 9988 80688 0 0 3 0x14200 bored systq 58519 1340 0 0 3 0x40014200 bored softclock 72026 191746 0 0 3 0x40014200 idle0 85164 120103 0 0 3 0x14200 bored smr 1 385018 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 45457 (systqmp) thread 0xffff800020a28000 (149655) shared rwlock pools r = 0 (0xffffffff82482650) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #1 pool_gc_pages+0x21 sys/kern/subr_pool.c:1563 #2 taskq_thread+0x9c sys/kern/kern_task.c:369 #3 proc_trampoline+0x1c shared rwlock systqmp r = 0 (0xffffffff824863b0) #0 witness_lock+0x52e sys/kern/subr_witness.c:1163 #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 9544 6425K 7267K 78643K 11180 0 pcb 13 8K 8K 78643K 61 0 rtable 106 3K 4K 78643K 272 0 ifaddr 84 15K 15K 78643K 118 0 counters 39 33K 33K 78643K 39 0 ioctlops 0 0K 4K 78643K 1483 0 iov 0 0K 16K 78643K 39 0 mount 1 1K 1K 78643K 1 0 vnodes 1229 77K 77K 78643K 1396 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 9 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 1K 78643K 33 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 196K 290K 78643K 12766 0 file desc 5 13K 25K 78643K 209 0 sigio 0 0K 0K 78643K 1 0 proc 61 63K 95K 78643K 462 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 7 0 in_multi 43 2K 2K 78643K 62 0 ether_multi 1 0K 0K 78643K 4 0 mrt 0 0K 0K 78643K 4 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 73 334K 334K 78643K 73 0 exec 0 0K 1K 78643K 231 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 115 70K 70K 78643K 1664 0 UVM aobj 15 2K 2K 78643K 17 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 8 0 NDP 15 0K 0K 78643K 24 0 temp 133 3008K 3072K 78643K 8048 0 kqueue 3 4K 8K 78643K 14 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 31 0 29 1 0 1 1 0 8 0 rtentry 112 53 0 10 2 0 2 2 0 8 0 unpcb 120 117 0 107 1 0 1 1 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpqe 32 633 0 633 1 1 0 1 0 8 0 tcpcb 544 61 0 57 1 0 1 1 0 8 0 inpcb 280 231 0 224 3 2 1 2 0 8 0 rttmr 72 2 0 2 1 1 0 1 0 8 0 nd6 48 6 0 3 1 0 1 1 0 8 0 ppxss 1128 2 0 2 2 2 0 1 0 8 0 pffrag 232 1 0 1 1 1 0 1 0 482 0 pffrnode 88 1 0 1 1 1 0 1 0 8 0 pffrent 40 45 0 45 1 1 0 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 23 0 5 1 0 1 1 0 8 0 pfstkey 112 23 0 5 1 0 1 1 0 8 0 pfstate 328 23 0 5 2 0 2 2 0 8 0 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 2 0 0 2 0 2 2 0 8 0 art_heap4 256 277 0 73 15 1 14 15 0 8 0 art_table 32 279 0 73 2 0 2 2 0 8 0 art_node 16 52 0 12 1 0 1 1 0 8 0 sysvmsgpl 40 21 0 11 1 0 1 1 0 8 0 semupl 112 3 0 3 1 1 0 1 0 8 0 semapl 112 31 0 21 1 0 1 1 0 8 0 shmpl 112 15 0 2 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 1721 0 312 46 0 46 46 0 8 0 ffsino 272 1721 0 312 95 0 95 95 0 8 0 nchpl 144 2285 0 666 61 0 61 61 0 8 0 uvmvnodes 72 1881 0 0 35 0 35 35 0 8 0 vnodes 208 1881 0 0 99 0 99 99 0 8 0 namei 1024 6489 0 6489 2 1 1 1 0 8 1 percpumem 16 30 0 0 1 0 1 1 0 8 0 vcpupl 1984 5 0 0 1 0 1 1 0 8 0 vmpool 560 7 0 2 1 0 1 1 0 8 0 scxspl 192 6325 0 6325 7 6 1 6 0 8 1 plimitpl 152 25 0 17 1 0 1 1 0 8 0 sigapl 432 408 0 393 3 1 2 3 0 8 0 futexpl 56 3659 0 3658 1 0 1 1 0 8 0 knotepl 112 67 0 48 1 0 1 1 0 8 0 kqueuepl 104 34 0 31 1 0 1 1 0 8 0 pipelkpl 48 119 0 109 1 0 1 1 0 8 0 pipepl 120 238 0 219 1 0 1 1 0 8 0 fdescpl 496 409 0 393 3 0 3 3 0 8 0 filepl 152 2869 0 2763 8 2 6 6 0 8 1 lockfpl 104 124 0 123 1 0 1 1 0 8 0 lockfspl 48 59 0 58 1 0 1 1 0 8 0 sessionpl 112 18 0 7 1 0 1 1 0 8 0 pgrppl 48 20 0 9 1 0 1 1 0 8 0 ucredpl 96 492 0 483 1 0 1 1 0 8 0 zombiepl 144 393 0 393 2 1 1 1 0 8 1 processpl 896 425 0 393 4 0 4 4 0 8 0 procpl 632 874 0 831 6 1 5 5 0 8 1 sosppl 128 2 0 2 1 0 1 1 0 8 1 sockpl 384 383 0 364 6 2 4 4 0 8 2 mcl64k 65536 259 0 0 33 0 33 33 0 8 1 mcl16k 16384 2 0 0 1 0 1 1 0 8 0 mcl12k 12288 3 0 0 1 0 1 1 0 8 0 mcl9k 9216 2 0 0 1 0 1 1 0 8 0 mcl8k 8192 2 0 0 1 0 1 1 0 8 0 mcl4k 4096 5 0 0 1 0 1 1 0 8 0 mcl2k2 2112 2 0 0 1 0 1 1 0 8 0 mcl2k 2048 199 0 0 24 0 24 24 0 8 0 mtagpl 80 16 0 0 1 0 1 1 0 8 0 mbufpl 256 367 0 0 24 1 23 23 0 8 0 bufpl 280 6732 0 1340 386 0 386 386 0 8 0 anonpl 16 60375 0 45178 94 9 85 93 0 125 22 amapchunkpl 152 2110 0 1966 8 0 8 8 0 158 0 amappl16 192 2302 0 1478 64 20 44 64 0 8 2 amappl15 184 58 0 54 1 0 1 1 0 8 0 amappl14 176 31 0 26 1 0 1 1 0 8 0 amappl13 168 86 0 85 1 0 1 1 0 8 0 amappl12 160 96 0 94 2 1 1 1 0 8 0 amappl11 152 55 0 40 1 0 1 1 0 8 0 amappl10 144 25 0 17 1 0 1 1 0 8 0 amappl9 136 612 0 608 1 0 1 1 0 8 0 amappl8 128 120 0 101 1 0 1 1 0 8 0 amappl7 120 103 0 91 1 0 1 1 0 8 0 amappl6 112 56 0 50 1 0 1 1 0 8 0 amappl5 104 221 0 206 1 0 1 1 0 8 0 amappl4 96 751 0 719 1 0 1 1 0 8 0 amappl3 88 129 0 121 1 0 1 1 0 8 0 amappl2 80 2306 0 2233 3 1 2 3 0 8 0 amappl1 72 18981 0 18519 27 17 10 21 0 8 0 amappl 80 1135 0 1088 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 16 0 2 1 0 1 1 0 8 0 uaddrrnd 24 416 0 395 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 416 0 395 1 0 1 1 0 8 0 vmmpekpl 168 6972 0 6936 2 0 2 2 0 8 0 vmmpepl 168 57728 0 55709 123 18 105 112 0 357 15 vmsppl 368 415 0 395 3 0 3 3 0 8 1 pdppl 4096 839 0 795 8 1 7 7 0 8 1 pvpl 32 185411 0 167000 220 11 209 216 0 265 57 pmappl 232 415 0 395 3 1 2 2 0 8 0 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 217 0 7 7 0 7 7 0 8 0