[FreeBSD-Announce] FreeBSD Errata Notice FreeBSD-EN-21:26.libevent

From: FreeBSD Errata Notices <errata-notices_at_freebsd.org>
Date: Thu, 04 Nov 2021 05:05:19 UTC
Hash: SHA512

FreeBSD-EN-21:26.libevent                                       Errata Notice
                                                          The FreeBSD Project

Topic:          libevent1 ABI breakage

Category:       core
Module:         libevent1
Announced:      2021-11-03
Affects:        FreeBSD 13.0
Corrected:      2021-04-01 17:29:20 UTC (stable/13, 13.0-STABLE)
                2021-11-03 20:37:22 UTC (releng/13.0, 13.0-RELEASE-p5)

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

libevent1 is a version of libevent in the base system used in ftp-proxy(8) and

II.  Problem Description

libevent1 maintains a local copy of some structure definitions from system
headers to simplify consumers of the library.  One of these structures no
longer matched the corresponding system definition, causing inconsistent views
of the `struct event` and `struct bufferevent` layouts.

III. Impact

ftp-proxy(8) will no longer handle incoming connections, ypldap(8) is likely
affected as well.

IV.  Workaround

No workaround is available.

V.   Solution

Upgrade your system to a supported FreeBSD stable or release / security
branch (releng) dated after the correction date.  No reboot will be required,
but ftp-proxy and ypldap will need to be restarted.

Perform one of the following:

1) To update your system via a binary patch:

Systems running a RELEASE version of FreeBSD on the amd64, i386, or
(on FreeBSD 13 and later) arm64 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.

# fetch https://security.FreeBSD.org/patches/EN-21:26/libevent.patch
# fetch https://security.FreeBSD.org/patches/EN-21:26/libevent.patch.asc
# gpg --verify libevent.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 <URL:https://www.FreeBSD.org/handbook/makeworld.html>.

Restart the applicable daemons, or reboot the system.

VI.  Correction details

This issue is corrected by the corresponding Git commit hash or Subversion
revision number in the following stable and release branches:

Branch/path                             Hash                     Revision
- -------------------------------------------------------------------------
stable/13/                              e0ad785a5d29    stable/13-n245086
releng/13.0/                            5cd45ad4784b  releng/13.0-n244761
- -------------------------------------------------------------------------

Run the following command to see which files were modified by a
particular commit:

# git show --stat <commit hash>

Or visit the following URL, replacing NNNNNN with the hash:


To determine the commit count in a working tree (for comparison against
nNNNNNN in the table above), run:

# git rev-list --count --first-parent HEAD

Or visit the following URL, replacing NNNNNN with the revision number:


VII. References


The latest revision of this advisory is available at