============================================================================= FreeBSD-EN-XX:XX:zfs Errata Notice The FreeBSD Project Topic: zfs receive Category: core Module: libzfs Announced: 2020-XX-XX Credits: Affects: FreeBSD 12.2 Corrected: 2020-12-01 08:15:18 UTC (stable/12, 12.2-STABLE) 2020-XX-XX XX:XX:XX UTC (releng/12.2, 12.2-RELEASE-pXX) For general information regarding FreeBSD Errata Notices and Security Advisories, including descriptions of the fields above, security branches, and the following sections, please visit . I. Background The zfs send/receive commands are used to efficiently copy datasets from one location to another. With the -i or -I flags, zfs send can incrementally update an already-copied dataset. When using the -R flag with zfs send and the -F flag with zfs receive, zfs receive will delete any snapshots on the destination that have already been deleted on the source. II. Problem Description A regression in FreeBSD 12.2 causes zfs receive to fail to delete snapshots that have been deleted on the source side. III. Impact Backup and replication systems based on ZFS send/receive that manage snapshots solely on the source side will fail to delete snapshots on the destination side. This may lead to out-of-space conditions on the destination. IV. Workaround Errant snapshots can be manually removed from the destination with "zfs destroy". Backup and replication systems that don't use the -R flag with zfs send will be unaffected. For example, sysutils/zrepl is unaffected. V. Solution Upgrade your system to a supported FreeBSD stable or release / security branch (releng) dated after the correction date. Perform one of the following: 1) To update your system via a binary patch: Systems running a RELEASE version of FreeBSD on the i386 or amd64 platforms can be updated via the freebsd-update(8) utility: # freebsd-update fetch # freebsd-update install 2) To update your system via a source code patch: The following patches have been verified to apply to the applicable FreeBSD release branches. a) Download the relevant patch from the location below, and verify the detached PGP signature using your PGP utility. [FreeBSD 11.4] # fetch https://security.FreeBSD.org/patches/EN-XX:XX/XXXX.patch # fetch https://security.FreeBSD.org/patches/EN-XX:XX/XXXX.patch.asc # gpg --verify XXXX.patch.asc b) Apply the patch. Execute the following commands as root: # cd /usr/src # patch < /path/to/patch c) Recompile the operating system using buildworld and installworld as described in . Restart all daemons that link directly to libzfs.so. A restart is not required for daemons that invoke the zfs executable. VI. Correction details The following list contains the correction revision numbers for each affected branch. Branch/path Revision ------------------------------------------------------------------------- stable/12/ r368233 releng/12.2/ rXXXXXX ------------------------------------------------------------------------- To see which files were modified by a particular revision, run the following command, replacing NNNNNN with the revision number, on a machine with Subversion installed: # svn diff -cNNNNNN --summarize svn://svn.freebsd.org/base Or visit the following URL, replacing NNNNNN with the revision number: VII. References The latest revision of this advisory is available at