panic: pool_do_get: shmpl free list modified: page 0xfffffd806be66000; item addr 0xfffffd806be663f8; offset 0x0=0x0 != 0x748129576bed55eb Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *350056 25392 0 0 0x4000000 0K syz-executor db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83352290) at panic+0x1e5 sys/kern/subr_prf.c:198 pool_do_get(ffffffff83942fc0,1,ffff80003c4eed08) at pool_do_get+0x592 pool_get(ffffffff83942fc0,1) at pool_get+0x149 shmget_allocate_segment(ffff8000ffff82b0,ffff80003c4eef60,4,ffff80003c4eeeb0) at shmget_allocate_segment+0x1a7 sys_shmget(ffff8000ffff82b0,ffff80003c4eef60,ffff80003c4eeeb0) at sys_shmget+0x1b2 sys/kern/sysv_shm.c:482 syscall(ffff80003c4eef60) at syscall+0xb08 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c4eef60) at syscall+0xb08 sys/arch/amd64/amd64/trap.c:577 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x4c6966276e0, count: 7 https://www.openbsd.org/ddb.html describes the minimum info required in bug reports. Insufficient info makes it difficult to find and fix bugs.