login: panic: pool_do_get: mbufpl free list modified: page 0xffffff006f34f000; item addr 0xffffff006f34f800; offset 0x0=0x394594b306000100 != 0x394594b3b883400e Stopped at db_enter+0xa: popq %rbp TID PID UID PRFLAGS PFLAGS CPU COMMAND *360869 71578 0 0 0x4000000 0 syz-executor0 db_enter() at db_enter+0xa panic() at panic+0x147 pool_do_get(2,ffffffff81ee0690,ffffff006f34f600) at pool_do_get+0x3ae pool_get(c,0) at pool_get+0x77 m_copyback(ffffff0078c9c127,ffffff006f34f600,40,100,100) at m_copyback+0x344 swofp_send_error(ffffff006f34f600,ffff800000aca000,ffff800000ad3300,0) at swofp_send_error+0xac swofp_input(ffff800000aca000,ffff800021148148) at swofp_input+0x126 switchwrite(ffffff006d42f270,ffffff006d42f270,ffff800021148328) at switchwrite+0x30e spec_write(ffffffff81e20158) at spec_write+0xa0 VOP_WRITE(1,ffffff006d42f270,1,ffffff006fa70d98) at VOP_WRITE+0x65 vn_write(ffffff006fa70d98,ffff800021148328,ffd4) at vn_write+0x161 dofilewritev(ffff800021148450,1,ffff800021148468,ffff8000ffffd2c8,0) at dofilewritev+0x13e sys_pwritev(ffff8000211484f0,ffff8000ffffd2c8,ffff800021060948) at sys_pwritev+0xbf syscall(0) at syscall+0x3e4 end trace frame: 0xffff800021148570, 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> ddb> set $lines = 0 ddb> show panic pool_do_get: mbufpl free list modified: page 0xffffff006f34f000; item addr 0xffffff006f34f800; offset 0x0=0x394594b306000100 != 0x394594b3b883400e ddb> trace db_enter() at db_enter+0xa panic() at panic+0x147 pool_do_get(2,ffffffff81ee0690,ffffff006f34f600) at pool_do_get+0x3ae pool_get(c,0) at pool_get+0x77 m_copyback(ffffff0078c9c127,ffffff006f34f600,40,100,100) at m_copyback+0x344 swofp_send_error(ffffff006f34f600,ffff800000aca000,ffff800000ad3300,0) at swofp_send_error+0xac swofp_input(ffff800000aca000,ffff800021148148) at swofp_input+0x126 switchwrite(ffffff006d42f270,ffffff006d42f270,ffff800021148328) at switchwrite+0x30e spec_write(ffffffff81e20158) at spec_write+0xa0 VOP_WRITE(1,ffffff006d42f270,1,ffffff006fa70d98) at VOP_WRITE+0x65 vn_write(ffffff006fa70d98,ffff800021148328,ffd4) at vn_write+0x161 dofilewritev(ffff800021148450,1,ffff800021148468,ffff8000ffffd2c8,0) at dofilewritev+0x13e sys_pwritev(ffff8000211484f0,ffff8000ffffd2c8,ffff800021060948) at sys_pwritev+0xbf syscall(0) at syscall+0x3e4 Xsyscall(6,0,ffffffffffffffb8,0,4,6b4dd2c3010) at Xsyscall+0x128 end of kernel end trace frame: 0x6b6ef02c200, count: -15 ddb> show registers rdi 0xffffffff81e02300 kprintf_mutex rsi 0x5 rbp 0xffff800021147e50 rbx 0xffff800021147ef0 rdx 0x3fd rcx 0 rax 0 r8 0xffff800021147e20 r9 0x8080808080808080 r10 0x394594b306000100 r11 0xffffffff81413330 x86_bus_space_io_read_1 r12 0x3000000008 r13 0xffff800021147e60 r14 0x100 r15 0xffffffff81c48812 cy_pio_rec+0x125af rip 0xffffffff8159c7ca db_enter+0xa cs 0x8 rflags 0x246 rsp 0xffff800021147e50 ss 0x10 db_enter+0xa: popq %rbp ddb> show proc PROC (syz-executor0) pid=360869 stat=onproc flags process=0 proc=4000000 pri=50, usrpri=50, nice=20 forw=0xffffffffffffffff, list=0xffff8000ffffc260,0xffffffff81ea6dd0 process=0xffff800021060948 user=0xffff800021143000, vmspace=0xffffff007f12b738 estcpu=15, cpticks=1, pctcpu=0.0 user=0, sys=1, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 71578 29390 9597 0 2 0 syz-executor0 *71578 360869 9597 0 7 0x4000000 syz-executor0 9597 281977 53542 0 3 0x82 nanosleep syz-executor0 53542 380558 84670 0 3 0x82 thrsleep syz-execprog 53542 344688 84670 0 3 0x4000082 thrsleep syz-execprog 53542 33027 84670 0 3 0x4000082 thrsleep syz-execprog 53542 375882 84670 0 3 0x4000082 thrsleep syz-execprog 53542 453507 84670 0 3 0x4000082 kqread syz-execprog 53542 248819 84670 0 3 0x4000082 thrsleep syz-execprog 53542 33585 84670 0 3 0x4000082 thrsleep syz-execprog 84670 269404 41716 0 3 0x10008a pause ksh 41716 60724 2362 0 3 0x92 select sshd 21518 232842 1 0 3 0x100083 ttyin getty 2362 99076 1 0 3 0x80 select sshd 21697 355402 35107 73 3 0x100090 kqread syslogd 35107 64572 1 0 3 0x100082 netio syslogd 58616 331092 1 77 3 0x100090 poll dhclient 96846 165184 1 0 3 0x80 poll dhclient 46493 266240 0 0 2 0x14200 zerothread 96098 319507 0 0 3 0x14200 aiodoned aiodoned 82503 329550 0 0 3 0x14200 syncer update 11599 130965 0 0 3 0x14200 cleaner cleaner 28805 170644 0 0 3 0x14200 reaper reaper 96738 134418 0 0 3 0x14200 pgdaemon pagedaemon 25584 379985 0 0 3 0x14200 bored crynlk 81788 474077 0 0 3 0x14200 bored crypto 78297 206717 0 0 3 0x40014200 acpi0 acpi0 67701 442996 0 0 3 0x14200 bored softnet 9112 220557 0 0 3 0x14200 bored systqmp 20967 429966 0 0 3 0x14200 bored systq 68419 287349 0 0 3 0x40014200 bored softclock 41848 453953 0 0 3 0x40014200 idle0 1 115092 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb>