panic: pool_p_free: tcpqe free list modified: page 0xfffffd8068ffc000; item addr 0xfffffd8068ffc000; offset 0x0=0x0 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 458554 89127 0 0x2 0x4000000 0 syz-fuzzer *298775 3732 0 0x14000 0x200 1 systqmp db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff8222c086) at panic+0x15c sys/kern/subr_prf.c:207 pool_p_free(ffffffff82630bf0,fffffd8068ffcf90) at pool_p_free+0x1de sys/kern/subr_pool.c:983 pool_gc_pages(0) at pool_gc_pages+0x255 sys/kern/subr_pool.c:1578 taskq_thread(ffffffff824952b0) 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: tcpqe free list modified: page 0xfffffd8068ffc000; item addr 0xfffffd8068ffc000; offset 0x0=0x0 ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff8222c086) at panic+0x15c sys/kern/subr_prf.c:207 pool_p_free(ffffffff82630bf0,fffffd8068ffcf90) at pool_p_free+0x1de sys/kern/subr_pool.c:983 pool_gc_pages(0) at pool_gc_pages+0x255 sys/kern/subr_pool.c:1578 taskq_thread(ffffffff824952b0) 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 0xffff800020a49ac0 rbx 0xffff800020a49b70 rdx 0xffff800020a28000 rcx 0 rax 0 r8 0xffffffff81f53faf kprintf+0x16f r9 0x1 r10 0x25 r11 0xfa08ce69040bdf5b r12 0x3000000008 r13 0xffff800020a49ad0 r14 0x100 r15 0x1 rip 0xffffffff81e05b48 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020a49ab0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (systqmp) pid=298775 stat=onproc flags process=14000 proc=200 pri=32, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff800020a28750,0xffff800020a28280 process=0xffff800020a2ab40 user=0xffff800020a44000, vmspace=0xffffffff8263d340 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 27762 509410 17267 0 2 0 syz-executor.1 27762 95017 17267 0 2 0x4000000 syz-executor.1 80772 329421 0 0 3 0x14200 bored sosplice 17267 205265 89127 0 2 0x482 syz-executor.1 78109 454403 89127 0 2 0x482 syz-executor.0 89127 513843 29129 0 3 0x82 thrsleep syz-fuzzer 89127 458554 29129 0 7 0x4000002 syz-fuzzer 89127 294236 29129 0 2 0x4000002 syz-fuzzer 89127 430914 29129 0 3 0x4000082 thrsleep syz-fuzzer 89127 219948 29129 0 3 0x4000082 thrsleep syz-fuzzer 89127 361999 29129 0 3 0x4000082 thrsleep syz-fuzzer 89127 450398 29129 0 3 0x4000082 kqread syz-fuzzer 89127 90692 29129 0 3 0x4000082 thrsleep syz-fuzzer 89127 335586 29129 0 3 0x4000082 thrsleep syz-fuzzer 89127 161013 29129 0 3 0x4000082 thrsleep syz-fuzzer 29129 43826 83543 0 3 0x10008a pause ksh 83543 30147 65656 0 3 0x92 select sshd 45595 38479 1 0 3 0x100083 ttyin getty 65656 387187 1 0 3 0x80 select sshd 33057 321799 12804 74 2 0x100492 pflogd 12804 451977 1 0 3 0x80 netio pflogd 67359 77492 83282 73 2 0x100490 syslogd 83282 493608 1 0 3 0x100082 netio syslogd 34276 367805 1 77 3 0x100090 poll dhclient 40653 442581 1 0 3 0x80 poll dhclient 63058 171767 0 0 3 0x14200 pgzero zerothread 80109 60350 0 0 3 0x14200 aiodoned aiodoned 92123 60180 0 0 2 0x14200 update 17752 432526 0 0 3 0x14200 cleaner cleaner 93745 115083 0 0 3 0x14200 reaper reaper 21029 60454 0 0 3 0x14200 pgdaemon pagedaemon 38517 21504 0 0 3 0x14200 bored crynlk 80783 246429 0 0 3 0x14200 bored crypto 82375 224117 0 0 3 0x40014200 acpi0 acpi0 65957 209901 0 0 3 0x40014200 idle1 75606 356848 0 0 3 0x14200 bored softnet * 3732 298775 0 0 7 0x14200 systqmp 9795 121728 0 0 3 0x14200 bored systq 57423 176881 0 0 2 0x40014200 softclock 67995 174311 0 0 3 0x40014200 idle0 87622 201602 0 0 2 0x14200 smr 1 268763 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 3732 (systqmp) thread 0xffff800020a28000 (298775) shared rwlock pools r = 0 (0xffffffff824ef670) #0 witness_lock+0x52e sys/kern/subr_witness.c:1164 #1 pool_gc_pages+0x21 sys/kern/subr_pool.c:1555 #2 taskq_thread+0x9c sys/kern/kern_task.c:369 #3 proc_trampoline+0x1c shared rwlock systqmp r = 0 (0xffffffff82495310) #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 9502 6418K 6794K 78643K 10786 0 pcb 13 8K 8K 78643K 41 0 rtable 108 4K 4K 78643K 242 0 ifaddr 62 12K 12K 78643K 89 0 counters 45 34K 34K 78643K 53 0 ioctlops 0 0K 4K 78643K 1477 0 iov 0 0K 12K 78643K 13 0 mount 1 1K 1K 78643K 1 0 vnodes 1217 76K 77K 78643K 1279 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 12 0K 0K 78643K 28 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 196K 290K 78643K 12766 0 file desc 6 17K 25K 78643K 118 0 proc 61 63K 95K 78643K 442 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 13 0 in_multi 33 2K 2K 78643K 44 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 43 201K 201K 78643K 43 0 exec 0 0K 1K 78643K 215 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 116 22K 22K 78643K 1336 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 19 0 NDP 10 0K 0K 78643K 18 0 temp 101 3012K 3076K 78643K 7460 0 kqueue 3 4K 10K 78643K 11 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 47 0 3 2 0 2 2 0 8 0 unpcb 120 89 0 79 1 0 1 1 0 8 0 syncache 264 6 0 6 2 1 1 1 0 8 1 tcpqe 32 89 0 89 1 1 0 1 0 8 0 tcpcb 544 40 0 36 1 0 1 1 0 8 0 inpcb 280 147 0 140 2 0 2 2 0 8 1 rttmr 72 2 0 2 1 0 1 1 0 8 1 nd6 48 4 0 0 1 0 1 1 0 8 0 ppxss 1128 2 0 2 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 19 0 0 1 0 1 1 0 8 0 pfstkey 112 19 0 0 1 0 1 1 0 8 0 pfstate 328 19 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 256 213 0 0 14 0 14 14 0 8 0 art_table 32 214 0 0 2 0 2 2 0 8 0 art_node 16 46 0 6 1 0 1 1 0 8 0 sysvmsgpl 40 12 0 5 1 0 1 1 0 8 0 semupl 112 4 0 4 1 0 1 1 0 8 1 semapl 112 22 0 12 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 1564 0 156 46 0 46 46 0 8 0 ffsino 272 1564 0 156 95 0 95 95 0 8 0 nchpl 144 1946 0 326 61 0 61 61 0 8 0 uvmvnodes 72 1647 0 0 30 0 30 30 0 8 0 vnodes 208 1647 0 0 87 0 87 87 0 8 0 namei 1024 5259 0 5259 1 0 1 1 0 8 1 percpumem 16 37 0 4 1 0 1 1 0 8 0 scxspl 192 5637 0 5637 2 1 1 2 0 8 1 plimitpl 152 27 0 19 1 0 1 1 0 8 0 sigapl 432 317 0 301 3 0 3 3 0 8 1 futexpl 56 1837 0 1837 1 0 1 1 0 8 1 knotepl 112 62 0 43 1 0 1 1 0 8 0 kqueuepl 104 20 0 18 1 0 1 1 0 8 0 pipelkpl 48 116 0 106 1 0 1 1 0 8 0 pipepl 120 232 0 213 2 0 2 2 0 8 1 fdescpl 496 318 0 301 3 0 3 3 0 8 0 filepl 152 2005 0 1895 5 0 5 5 0 8 0 lockfpl 104 32 0 31 1 0 1 1 0 8 0 lockfspl 48 13 0 12 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 96 184 0 175 1 0 1 1 0 8 0 zombiepl 144 302 0 301 1 0 1 1 0 8 0 processpl 960 334 0 301 5 0 5 5 0 8 0 procpl 624 562 0 519 5 0 5 5 0 8 1 sockpl 400 267 0 248 4 0 4 4 0 8 2 mcl64k 65536 4 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 3 0 0 1 0 1 1 0 8 0 mcl2k 2048 160 0 0 19 0 19 19 0 8 0 mtagpl 80 9 0 0 1 0 1 1 0 8 0 mbufpl 256 188 0 0 12 0 12 12 0 8 0 bufpl 280 4354 0 201 297 0 297 297 0 8 0 anonpl 16 44532 0 28207 67 1 66 66 0 125 0 amapchunkpl 152 1601 0 1464 8 0 8 8 0 158 1 amappl16 192 1364 0 469 46 1 45 45 0 8 0 amappl15 184 58 0 54 1 0 1 1 0 8 0 amappl14 176 27 0 25 1 0 1 1 0 8 0 amappl13 168 1 0 1 1 1 0 1 0 8 0 amappl12 160 57 0 53 2 1 1 1 0 8 0 amappl11 152 60 0 44 1 0 1 1 0 8 0 amappl10 144 57 0 53 1 0 1 1 0 8 0 amappl9 136 600 0 597 1 0 1 1 0 8 0 amappl8 128 127 0 101 2 0 2 2 0 8 0 amappl7 120 143 0 131 1 0 1 1 0 8 0 amappl6 112 64 0 54 1 0 1 1 0 8 0 amappl5 104 191 0 175 1 0 1 1 0 8 0 amappl4 96 531 0 499 1 0 1 1 0 8 0 amappl3 88 159 0 150 1 0 1 1 0 8 0 amappl2 80 1647 0 1561 3 1 2 3 0 8 0 amappl1 72 16982 0 16508 26 14 12 21 0 8 2 amappl 80 811 0 766 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 24 318 0 301 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 318 0 301 1 0 1 1 0 8 0 vmmpekpl 168 6529 0 6494 2 0 2 2 0 8 0 vmmpepl 168 46564 0 44376 122 3 119 119 0 357 23 vmsppl 368 317 0 301 2 0 2 2 0 8 0 pdppl 4096 643 0 602 6 0 6 6 0 8 0 pvpl 32 152155 0 132589 161 0 161 161 0 265 2 pmappl 232 317 0 301 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