Kiconvtool

Jul 20, 2023

Tool to preload kernel iconv charset tables

On FreeBSD, it’s possible to allow plain users to mount filesystems without using su or sudo. This is enabled via vfs.usermount sysctl. However, if file name conversion is used when mounting a filesystem, in most cases mount will fail with `mount_XXX XXX_iconv Operation not permitted denied’ error. This is caused by the fact that character set conversion tables need to be loaded into kernel, but, apart from mounting, that’s not allowed to plain users, because charset tables are large enough to initiate a denial of service by filling kernel memory with many tables.

This utility allows you to load only specific charset tables into kernel, so usermounts with file name conversions won’t fail and in the same time it’s not possible to bring the system down by filling kernel memory.



Checkout these related ports:
  • Zxfer - Easily and reliably transfer ZFS filesystems
  • Ztop - Display ZFS dataset I/O in real time
  • Zsm - ZFS Snapshot Manager
  • Zsd - Destroys ZFS snapshots
  • Zrepl - ZFS dataset replication tool
  • Zrep - ZFS based replication and failover solution
  • Zpool-iostat-viz - ZFS pool I/O latency statistics
  • Zoxide - Fast cd alternative that learns your habits
  • Zogftw - Creates redundant backups on encrypted ZFS pools
  • Znapzend - ZFS-centric backup tool
  • Zisofs-tools - User utilities for zisofs
  • Zidrav - File corruption detection and repair program
  • Zfstools - OpenSolaris-compatible auto snapshotting for ZFS
  • Zfsnap2 - Portable performant script to make rolling ZFS snapshots easy
  • Zfsnap - Simple sh script to make zfs rolling snaphosts with cron