| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2024-50112: x86/lam: Disable ADDRESS_MASKING in most cases |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| x86/lam: Disable ADDRESS_MASKING in most cases |
| |
| Linear Address Masking (LAM) has a weakness related to transient |
| execution as described in the SLAM paper[1]. Unless Linear Address |
| Space Separation (LASS) is enabled this weakness may be exploitable. |
| |
| Until kernel adds support for LASS[2], only allow LAM for COMPILE_TEST, |
| or when speculation mitigations have been disabled at compile time, |
| otherwise keep LAM disabled. |
| |
| There are no processors in market that support LAM yet, so currently |
| nobody is affected by this issue. |
| |
| [1] SLAM: https://download.vusec.net/papers/slam_sp24.pdf |
| [2] LASS: https://lore.kernel.org/lkml/20230609183632.48706-1-alexander.shishkin@linux.intel.com/ |
| |
| [ dhansen: update SPECULATION_MITIGATIONS -> CPU_MITIGATIONS ] |
| |
| The Linux kernel CVE team has assigned CVE-2024-50112 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 6.6.59 with commit 60a5ba560f296ad8da153f6ad3f70030bfa3958f |
| Fixed in 6.11.6 with commit 690599066488d16db96ac0d6340f9372fc56f337 |
| Fixed in 6.12 with commit 3267cb6d3a174ff83d6287dcd5b0047bbd912452 |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2024-50112 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| arch/x86/Kconfig |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/60a5ba560f296ad8da153f6ad3f70030bfa3958f |
| https://git.kernel.org/stable/c/690599066488d16db96ac0d6340f9372fc56f337 |
| https://git.kernel.org/stable/c/3267cb6d3a174ff83d6287dcd5b0047bbd912452 |
