FreeBSD Errata Notices
2016-Oct-25 17:37 UTC
[FreeBSD-Announce] FreeBSD Errata Notice FreeBSD-EN-16:18.loader
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 ============================================================================FreeBSD-EN-16:18 Errata Notice The FreeBSD Project Topic: Loader may hang during boot Category: core Module: loader Announced: 2016-10-25 Affects: FreeBSD 11.0 Corrected: 2016-10-08 00:01:07 UTC (stable/11, 11.0-STABLE) 2016-10-25 16:50:10 UTC (releng/11.0, 11.0-RELEASE-p2) For general information regarding FreeBSD Errata Notices and Security Advisories, including descriptions of the fields above, security branches, and the following sections, please visit <URL:https://security.FreeBSD.org/>. I. Background The loader is the final stage (boot3) of the boot process and is responsible for loading the kernel and starting the operating system. GELIBoot is a feature present in the loader that allows it to boot the system from an encrypted disks. II. Problem Description A programming error in GELIBoot causes the loader to attempt to read past the end of the disk if the size of the final partition is not a multiple of 4 kB. III. Impact On most systems, reading past the end of the disk will result in the read failing, and the boot process will continue normally. On some systems, the read past the end of the disk will be retried a number of times and will result in the boot process being slower than usual. On Amazon EC2 instances, and possibly other virtualization platforms, this issue causes the boot process to hang and never complete. IV. Workaround No workaround is available, but systems with 4 kB aligned partitions will not result in an attempt to read past the end of the disk. V. Solution Perform one of the following: 1) Upgrade your system to a supported FreeBSD stable or release / security branch (releng) dated after the correction date. 2) 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 3) 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 11.0] # fetch https://security.FreeBSD.org/patches/EN-16:18/loader.patch # fetch https://security.FreeBSD.org/patches/EN-16:18/loader.patch.asc # gpg --verify loader.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>. VI. Correction details The following list contains the correction revision numbers for each affected branch. Branch/path Revision - ------------------------------------------------------------------------- stable/11/ r306834 releng/11.0/ r307930 - ------------------------------------------------------------------------- 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: <URL:https://svnweb.freebsd.org/base?view=revision&revision=NNNNNN> VII. References <URL:https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=213196> The latest revision of this advisory is available at <URL:https://security.FreeBSD.org/advisories/FreeBSD-EN-16:18.loader.asc> -----BEGIN PGP SIGNATURE----- iQIcBAEBCgAGBQJYD5UZAAoJEO1n7NZdz2rnNNEQAL+Rdn8eEtmUU4AVfa1pnIrc /+owfHzB6NS5N+qcsFJmWGyrP6X3HAgNTfiJuNdJBV8HgcAtCQCPie/jork9A/q1 U0ur8FDr91Y6Cr2H8BINmf7Oe3vwY6S7pPbwbHaHCzAAI/JyDtjGlN4VlEr7lKh/ 3J6xizMDHTBj198SopMIDUWl+qFeLxEMb60WV0Z8NDRyQzV0yXbveUkg35FZhqaW w/aAH0hTh3qhxjQCyh34GrJ/peuvPtWxZLfPP7zowIKKAGQR+PfFnN9PrGQFAzht yQVk8WrvTrlzZbay6U5BGFcwaxVSgW8PLIHET01BAyd//HBGdfofEMcVXoiQqf5x 1kX0fdiop02JZX49rzknAGtLlUivniBSCZTnPZrFCjhOHE+TZhhhnqB/jT+RBazx m5xFScvfcZZ8ZXK1e68Jn1/SpIOtX+lXmKpoFwE4HoPtJkZV3SDIRYgAsxuWRlMy R0I7HuGc7RgJNSJWFhGWcUkyq0yZhy7+x0vVzV3tDZClYrv82ZbVxzTCSCH2se3L TLnIruK3nPt4KPWPka7H0jaVzICjqJHzy30IsNMHYHZg8dQ0/CR7pYm2zgCu9B84 qbemY0YKlhsccM0/R/P9OMNDTcxP6l/Yhqb9A/upBhn2Vlw9OGamvuKfgX4WOTIE gOcI7hQW4U/U3ioTTS1T =vmGn -----END PGP SIGNATURE-----