CVE-2023-5370

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 ============================================================================= FreeBSD-SA-23:14.smccc Security Advisory The FreeBSD Project Topic: arm64 boot CPUs may lack speculative execution protections Category: core Module: arm64 Announced: 2023-10-03 Affects: FreeBSD 13.2 Corrected: 2023-09-25 12:13:47 UTC (stable/13, 13.2-STABLE) 2023-10-03 21:29:11 UTC (releng/13.2, 13.2-RELEASE-p4) CVE Name: CVE-2023-5370 For general information regarding FreeBSD Security Advisories, including descriptions of the fields above, security branches, and the following sections, please visit . I. Background To mitigate speculative execution side channel attacks on some AArch64 hardware the kernel can call into the boot firmware using the Secure Monitor Call Calling Convention (SMCCC) mechanism. To decide if the kernel needs to use the SMCCC mitigation on a given CPU it can query the firmware if the SMCCC workaround is present. II. Problem Description On CPU 0 the check for the SMCCC workaround is called before SMCCC support has been initialized. III. Impact No speculative execution workarounds are installed on CPU 0. IV. Workaround No workaround is available. Not all AArch64 CPUs are affected. Systems where CPU 0 has the CSV2 and PSTATE.SSBS processor features are unaffected by the speculative execution attacks. The kernel will print the following under CPU 0 on unaffected CPUs: Processor Features 0 = <…CVS2…> Processor Features 1 = <…PSTATE.SSBS…> The Arm Cortex-A35, Cortex-A53, and Cortex-A55 CPUs are unaffected. V. Solution Upgrade your vulnerable 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 vulnerable 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 # shutdown -r +10min “Rebooting for a security update” 2) To update your vulnerable 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/SA-23:14/smccc.patch # fetch https://security.FreeBSD.org/patches/SA-23:14/smccc.patch.asc # gpg --verify smccc.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 and 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/ 4df1447f2c76 stable/13-n256420 releng/13.2/ 485912e051bb releng/13.2-n254637 - ------------------------------------------------------------------------- Run the following command to see which files were modified by a particular commit: # git show --stat 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 VII. References The latest revision of this advisory is available at -----BEGIN PGP SIGNATURE----- iQIzBAEBCgAdFiEEthUnfoEIffdcgYM7bljekB8AGu8FAmUclU8ACgkQbljekB8A Gu8zqQ//bCjUB/hXZxypEFmnnnyUPr0Y/pzHd1i7EcIFQubd6kosUw4k2VGzwOsi /BwKU4W/MrUyr/wwSkjJ/lmeA+CRX2TAPWPTPC0umnN58fOXRqhKpVAi0yfho+L9 lYUfdLWM0xS4XWsZk7DapjfN8XznLnn6iQrWmFLmZd0ViJFGkGJcxjdWr7aSs7ZX C8v8GoqFx6GUUdOgRERdpZ/2mxi7ibs9LbCt4PUTwKV8clAmq4w4Mv+q4xfZPSnM nXGrTd+t2G5ZrmEZ9Rq32C9JqGaAaQUTp/NsOw8yQq5YVBXanA12VJLx2kdoVKsj 84e3rJz/QTpXTpgiSkVmWdT3ziZW8Zs9aygvUXyzK6C/s2ZiKd8o65dnF3MGCyJs Y7aNgAS51mX/fgPyXwicF/eYA1nm/1AJAK9J/eUBbsi+hu9DW5XjpiLUYAe10KKf 9XsgJ1vTJMKXIv/UAlN0d78SfSfcGyUCbH0qk7zCzw9XfLYj+r9a7de/vnAc0qtm 8Gh0hqbacA6dqtxrNEDC9R1Tp6inf0YYR6gP5HPjjy96FvfZCGmHk5XUmbmk4C4T UylvLXrO4gJiyBXhdZ3P3Mib6HdMWkLMRh095Y2revdAGMv0BrGs3G+eaMVIgNt2 puELCPfLgJF1ljcHV8svdQcuy0Fea2R2R22cqwsT1vPuKqgmP60= =lOTX -----END PGP SIGNATURE-----