panic: pool_p_free: pffrnode free list modified: page 0xfffffd8063609000; item addr 0xfffffd8063609000; offset 0x0=0x0 Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 286005 87646 0 0 0 0 syz-executor.0 * 60999 78439 0 0x14000 0x200 1 systqmp db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff8222e1d5) at panic+0x15c sys/kern/subr_prf.c:207 pool_p_free(ffffffff82640138,fffffd8063609f90) 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(ffffffff824584e0) 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: pffrnode free list modified: page 0xfffffd8063609000; item addr 0xfffffd8063609000; offset 0x0=0x0 ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:398 panic(ffffffff8222e1d5) at panic+0x15c sys/kern/subr_prf.c:207 pool_p_free(ffffffff82640138,fffffd8063609f90) 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(ffffffff824584e0) 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 0xffff800020a496e0 rbx 0xffff800020a49790 rdx 0xffff800020a28000 rcx 0 rax 0 r8 0xffffffff8167311f kprintf+0x16f r9 0x1 r10 0x25 r11 0xce134e928eca8ba2 r12 0x3000000008 r13 0xffff800020a496f0 r14 0x100 r15 0x1 rip 0xffffffff817078e8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020a496d0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (systqmp) pid=60999 stat=onproc flags process=14000 proc=200 pri=32, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff800020a284e0,0xffff800020a28280 process=0xffff800020a2b2c0 user=0xffff800020a44000, vmspace=0xffffffff826596d0 estcpu=0, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 1308 183533 92241 0 2 0 syz-executor.1 87646 286005 64896 0 7 0 syz-executor.0 87646 84975 64896 0 2 0x4000000 syz-executor.0 87646 5991 64896 0 2 0x4000000 syz-executor.0 87646 367314 64896 0 2 0x4000000 syz-executor.0 87646 128786 64896 0 2 0x4000000 syz-executor.0 73732 238976 1 0 3 0x80 nanosleep init 12958 257858 0 0 3 0x14200 bored sosplice 92241 134668 89733 0 3 0x82 nanosleep syz-executor.1 64896 375993 89733 0 3 0x82 nanosleep syz-executor.0 89733 503570 44828 0 3 0x82 thrsleep syz-fuzzer 89733 8374 44828 0 3 0x4000082 nanosleep syz-fuzzer 89733 89981 44828 0 3 0x4000082 kqread syz-fuzzer 89733 10736 44828 0 3 0x4000082 thrsleep syz-fuzzer 89733 403531 44828 0 3 0x4000082 thrsleep syz-fuzzer 89733 408143 44828 0 3 0x4000082 thrsleep syz-fuzzer 89733 82712 44828 0 3 0x4000082 thrsleep syz-fuzzer 89733 66958 44828 0 3 0x4000082 thrsleep syz-fuzzer 89733 18671 44828 0 3 0x4000082 thrsleep syz-fuzzer 89733 315921 44828 0 3 0x4000082 thrsleep syz-fuzzer 44828 484205 25461 0 3 0x10008a pause ksh 25461 508211 75077 0 3 0x92 select sshd 75077 428035 1 0 3 0x80 select sshd 42177 62921 59761 74 3 0x100092 bpf pflogd 59761 334442 1 0 3 0x80 netio pflogd 92279 225678 1978 73 3 0x100090 kqread syslogd 1978 129399 1 0 3 0x100082 netio syslogd 41313 427440 1 77 3 0x100090 poll dhclient 44168 491925 1 0 3 0x80 poll dhclient 44462 349530 0 0 2 0x14200 zerothread 75203 19009 0 0 3 0x14200 aiodoned aiodoned 90365 74410 0 0 2 0x14200 update 51813 199885 0 0 3 0x14200 cleaner cleaner 59157 424987 0 0 3 0x14200 reaper reaper 69108 194476 0 0 3 0x14200 pgdaemon pagedaemon 7740 352551 0 0 3 0x14200 bored crynlk 41250 312420 0 0 3 0x14200 bored crypto 59007 323277 0 0 3 0x40014200 acpi0 acpi0 14597 184626 0 0 3 0x40014200 idle1 99282 365568 0 0 3 0x14200 bored softnet *78439 60999 0 0 7 0x14200 systqmp 41666 441765 0 0 3 0x14200 bored systq 32972 450362 0 0 3 0x40014200 bored softclock 1031 294929 0 0 3 0x40014200 idle0 20687 482593 0 0 3 0x14200 bored smr 1 272359 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 87646 (syz-executor.0) thread 0xffff800020ae7128 (286005) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff8263e0d8) #0 witness_lock+0x52e sys/kern/subr_witness.c:1164 #1 syscall+0x400 mi_syscall sys/sys/syscall_mi.h:93 [inline] #1 syscall+0x400 sys/arch/amd64/amd64/trap.c:570 #2 Xsyscall+0x128 Process 78439 (systqmp) thread 0xffff800020a28000 (60999) shared rwlock pools r = 0 (0xffffffff825118f0) #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 (0xffffffff82458540) #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 6410K 7634K 78643K 11095 0 pcb 13 8K 8K 78643K 59 0 rtable 104 3K 4K 78643K 269 0 ifaddr 67 14K 14K 78643K 88 0 counters 43 33K 34K 78643K 49 0 ioctlops 0 0K 4K 78643K 1545 0 iov 0 0K 20K 78643K 38 0 mount 1 1K 1K 78643K 1 0 vnodes 1229 77K 77K 78643K 1371 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 12 0K 0K 78643K 52 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1809 196K 290K 78643K 12766 0 file desc 6 17K 25K 78643K 184 0 sigio 0 0K 0K 78643K 8 0 proc 54 51K 95K 78643K 480 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 35 0 in_multi 51 2K 2K 78643K 94 0 ether_multi 1 0K 0K 78643K 3 0 mrt 0 0K 0K 78643K 8 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 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 109 22K 22K 78643K 1546 0 UVM aobj 16 2K 2K 78643K 16 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 38 0 NDP 10 0K 0K 78643K 20 0 temp 93 3010K 3077K 78643K 3546 0 kqueue 7 5K 16K 78643K 18 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 27 0 25 1 0 1 1 0 8 0 rtentry 112 61 0 19 2 0 2 2 0 8 0 unpcb 120 281 0 271 1 0 1 1 0 8 0 syncache 264 4 0 4 1 1 0 1 0 8 0 tcpqe 32 479 0 479 1 1 0 1 0 8 0 tcpcb 544 122 0 118 1 0 1 1 0 8 0 inpcb 280 462 0 455 3 0 3 3 0 8 2 rttmr 72 4 0 4 1 0 1 1 0 8 1 nd6 48 7 0 4 1 0 1 1 0 8 0 pkpcb 40 4 0 4 1 1 0 1 0 8 0 ppxss 1128 1 0 1 1 0 1 1 0 8 1 pffrag 232 2 0 2 1 1 0 1 0 482 0 pffrnode 88 2 0 2 1 1 0 1 0 8 0 pffrent 40 90 0 90 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 25 0 2 1 0 1 1 0 8 0 pfstkey 112 25 0 2 1 0 1 1 0 8 0 pfstate 328 25 0 2 3 0 3 3 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 256 283 0 87 14 0 14 14 0 8 0 art_table 32 284 0 87 2 0 2 2 0 8 0 art_node 16 60 0 21 1 0 1 1 0 8 0 sysvmsgpl 40 8 0 4 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 46 0 36 1 0 1 1 0 8 0 shmpl 112 14 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino1pl 128 1657 0 250 46 0 46 46 0 8 0 ffsino 272 1657 0 250 95 0 95 95 0 8 0 nchpl 144 2116 0 499 61 0 61 61 0 8 0 uvmvnodes 72 1822 0 0 34 0 34 34 0 8 0 vnodes 208 1822 0 0 96 0 96 96 0 8 0 namei 1024 5853 0 5853 1 0 1 1 0 8 1 percpumem 16 35 0 3 1 0 1 1 0 8 0 scxspl 192 6493 0 6493 8 3 5 7 0 8 5 plimitpl 152 28 0 21 1 0 1 1 0 8 0 sigapl 432 385 0 369 3 1 2 3 0 8 0 futexpl 56 3877 0 3877 1 0 1 1 0 8 1 knotepl 112 72 0 51 1 0 1 1 0 8 0 kqueuepl 104 38 0 34 1 0 1 1 0 8 0 pipelkpl 48 114 0 104 1 0 1 1 0 8 0 pipepl 120 228 0 209 1 0 1 1 0 8 0 fdescpl 496 386 0 369 3 0 3 3 0 8 0 filepl 152 2790 0 2688 6 0 6 6 0 8 2 lockfpl 104 65 0 64 1 0 1 1 0 8 0 lockfspl 48 18 0 17 1 0 1 1 0 8 0 sessionpl 112 19 0 9 1 0 1 1 0 8 0 pgrppl 48 21 0 11 1 0 1 1 0 8 0 ucredpl 96 150 0 141 1 0 1 1 0 8 0 zombiepl 144 369 0 369 1 0 1 1 0 8 1 processpl 960 402 0 369 5 0 5 5 0 8 0 procpl 624 771 0 725 4 0 4 4 0 8 0 sosppl 128 36 0 36 1 0 1 1 0 8 1 sockpl 400 777 0 758 6 0 6 6 0 8 4 mcl64k 65536 7 0 0 1 0 1 1 0 8 0 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 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 5 0 0 1 0 1 1 0 8 0 mcl4k 4096 7 0 0 1 0 1 1 0 8 0 mcl2k2 2112 1 0 0 1 0 1 1 0 8 0 mcl2k 2048 172 0 0 21 0 21 21 0 8 0 mtagpl 80 25 0 0 1 0 1 1 0 8 0 mbufpl 256 313 0 0 19 0 19 19 0 8 0 bufpl 280 4526 0 192 310 0 310 310 0 8 0 anonpl 16 53216 0 32773 84 1 83 83 0 125 0 amapchunkpl 152 2029 0 1867 8 0 8 8 0 158 0 amappl16 192 1863 0 740 57 0 57 57 0 8 0 amappl15 184 68 0 64 1 0 1 1 0 8 0 amappl14 176 29 0 27 1 0 1 1 0 8 0 amappl12 160 14 0 12 2 1 1 1 0 8 0 amappl11 152 54 0 39 1 0 1 1 0 8 0 amappl10 144 165 0 156 1 0 1 1 0 8 0 amappl9 136 600 0 597 1 0 1 1 0 8 0 amappl8 128 127 0 102 1 0 1 1 0 8 0 amappl7 120 252 0 240 1 0 1 1 0 8 0 amappl6 112 60 0 50 1 0 1 1 0 8 0 amappl5 104 134 0 120 1 0 1 1 0 8 0 amappl4 96 640 0 611 1 0 1 1 0 8 0 amappl3 88 117 0 110 1 0 1 1 0 8 0 amappl2 80 2161 0 2090 3 1 2 3 0 8 0 amappl1 72 18368 0 17926 27 16 11 21 0 8 0 amappl 80 1017 0 969 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 15 0 0 1 0 1 1 0 8 0 uaddrrnd 24 386 0 369 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 386 0 369 1 0 1 1 0 8 0 vmmpekpl 168 6926 0 6892 2 0 2 2 0 8 0 vmmpepl 168 54658 0 52292 124 14 110 113 0 357 7 vmsppl 368 385 0 369 2 0 2 2 0 8 0 pdppl 4096 779 0 738 6 0 6 6 0 8 0 pvpl 32 172883 0 148867 194 0 194 194 0 265 0 pmappl 232 385 0 369 2 1 1 2 0 8 0 extentpl 40 46 0 29 1 0 1 1 0 8 0 phpool 112 181 0 3 6 0 6 6 0 8 0