mport package installation can overwrite existing unmanaged or differently owned files

mport is the MidnightBSD Package Manager. Prior to 2.7.8, package installation lacked a preflight check for incoming non-directory assets that already existed on disk. The affected logic across libmport/check_preconditions.c, libmport/install_primative.c, and libmport/mport_private.h did not apply MPORT_PRECHECK_FILE_CONFLICTS, so a crafted or conflicting package could overwrite a file owned by another package or unmanaged by mport. The check is bypassed only when the operator explicitly enables mport->force. Privileged installation without that override could compromise local filesystem integrity and package database consistency. This issue is fixed in version 2.7.8.