FreeBSD Errata Notice FreeBSD-EN-24:05.tty
28 March, 2024 by errata-notices@freebsd.org | freebsd
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 ============================================================================= FreeBSD-EN-24:05.tty Erratum Notice The FreeBSD Project Topic: TTY Kernel Panic Category: core Module: kernel Announced: 2024-03-28 Affects: FreeBSD 13.2 and FreeBSD 14.0 Corrected: 2024-02-29 00:29:13 UTC (stable/14, 14.0-STABLE) 2024-03-28 05:06:21 UTC (releng/14.0, 14.0-RELEASE-p6) 2024-02-29 00:30:12 UTC (stable/13, 13.2-STABLE) 2024-03-28 05:07:53 UTC (releng/13.2, 13.2-RELEASE-p11) 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 tty(4) is the general terminal device. The kern.ttys sysctl provides tty information for tools such as `pstat -t`. FreeBSD-SA-24:02.tty addressed an information leak about outside processes from within a jail. II. Problem Description A missing check resulted in a null pointer dereference if a tty had a session associated, but no session leader. III. Impact Under certain conditions an unprivileged user could provoke a kernel panic. 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, and reboot. Perform one of the following: 1) To update your system via a binary patch: Systems running a RELEASE version of FreeBSD on the amd64 or arm64 platforms, or the i386 platform on FreeBSD 13, can be updated via the freebsd-update(8) utility: # freebsd-update fetch # freebsd-update install # shutdown -r +10min "Rebooting for an erratum update" 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-24:05/tty.patch # fetch https://security.FreeBSD.org/patches/EN-24:05/tty.patch.asc # gpg --verify tty.patch.asc b) Apply the patch. Execute the following commands as root: # cd /usr/src # patch < /path/to/patch c) Recompile your kernel as described in <URL:https://www.FreeBSD.org/handbook/kernelconfig.html> and reboot the system. VI. Correction details This issue is corrected as of the corresponding Git commit hash in the following stable and release branches: Branch/path Hash Revision - ------------------------------------------------------------------------- stable/14/ 8d22744f5be1 stable/14-n266915 releng/14.0/ a3ec3054762f releng/14.0-n265411 stable/13/ a60220bbb551 stable/13-n257543 releng/13.2/ f3195cc08ccc releng/13.2-n254662 - ------------------------------------------------------------------------- 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: <URL:https://cgit.freebsd.org/src/commit/?id=NNNNNN> 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 VII. References <URL:https://bugs.freebsd.org/bugzilla/show_bug.cgi?id'7240> <URL:https://bugs.freebsd.org/bugzilla/show_bug.cgi?id'7329> The latest revision of this advisory is available at <URL:https://security.FreeBSD.org/advisories/FreeBSD-EN-24:05.tty.asc> -----BEGIN PGP SIGNATURE----- iQIzBAEBCgAdFiEEthUnfoEIffdcgYM7bljekB8AGu8FAmYFGaEACgkQbljekB8A Gu8NTw//Rqyq8heDUZZyz0TKMs/ObZY9h7VbL3Pces9mpnE6mgZx9g1kalo1xml3 x0kRIJ0L606oBxhrJYqam3DrcJsPWs/8LOmmUa9u4/M2sAPuw03pyPEYNnokhf05 NvC6mjNCpuJY4jzoa1hYdjvUHJe6u66reEoWuARPxoT6ZGPLiVhYPmoYIJFtoEAy tLEIH4GRjfRuOEgSDY7sIy5MoxjObBqPQl4VtbCSZDN/PN4z6WuxC/f2N0vpN1uq IyDGWCvEOa6g+7kDEiBJo4LRp30mQtMJalfQUlLm653Do2Jh6L5tUuQ+T0qIOlqc gTlKnnaa0m/hMUD9t4lJHQbLfGFaYpXbyJpblO8hPoM7Trk2vsoGubksMYZSRHIy /9IiZafdnNoHxa5+ZTRSqxYw9e38gwTlWsNjQpCezhtaZo0FWkhcgC7zUG+yMUXz zYhYXCQkZXpEvIg+BJs3ZdigGK7wRjC9qsC8jfnhOU+q452qqnKjg8bxJdGxBbZ0 HKFfAVgtqAEgU3PzPN7Nmu4QJ+VOu9L/e1mOhrqcmHtYDYLfdelCT8DjHj85oggn C5iDPG6AxnLczTlTxVsHTiQcmTy6awfeTf1N1JCbfZPovrO/CTaOLnMy/PNeZIml UnarxLtQNeK6BDKd0E/rEym9wL0YJ1Xj/3XE1qPAjz52YufRHHM=w167 -----END PGP SIGNATURE-----