| 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-2024-42230: powerpc/pseries: Fix scv instruction crash with kexec |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| powerpc/pseries: Fix scv instruction crash with kexec |
| |
| kexec on pseries disables AIL (reloc_on_exc), required for scv |
| instruction support, before other CPUs have been shut down. This means |
| they can execute scv instructions after AIL is disabled, which causes an |
| interrupt at an unexpected entry location that crashes the kernel. |
| |
| Change the kexec sequence to disable AIL after other CPUs have been |
| brought down. |
| |
| As a refresher, the real-mode scv interrupt vector is 0x17000, and the |
| fixed-location head code probably couldn't easily deal with implementing |
| such high addresses so it was just decided not to support that interrupt |
| at all. |
| |
| The Linux kernel CVE team has assigned CVE-2024-42230 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.9 with commit 7fa95f9adaee7e5cbb195d3359741120829e488b and fixed in 6.1.98 with commit c550679d604798d9fed8a5b2bb5693448a25407c |
| Issue introduced in 5.9 with commit 7fa95f9adaee7e5cbb195d3359741120829e488b and fixed in 6.6.39 with commit d10e3c39001e9194b9a1bfd6979bd3fa19dccdc5 |
| Issue introduced in 5.9 with commit 7fa95f9adaee7e5cbb195d3359741120829e488b and fixed in 6.9.9 with commit 8c6506616386ce37e59b2745fc481c6713fae4f3 |
| Issue introduced in 5.9 with commit 7fa95f9adaee7e5cbb195d3359741120829e488b and fixed in 6.10 with commit 21a741eb75f80397e5f7d3739e24d7d75e619011 |
| |
| 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-2024-42230 |
| 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/powerpc/kexec/core_64.c |
| arch/powerpc/platforms/pseries/kexec.c |
| arch/powerpc/platforms/pseries/pseries.h |
| arch/powerpc/platforms/pseries/setup.c |
| |
| |
| 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/c550679d604798d9fed8a5b2bb5693448a25407c |
| https://git.kernel.org/stable/c/d10e3c39001e9194b9a1bfd6979bd3fa19dccdc5 |
| https://git.kernel.org/stable/c/8c6506616386ce37e59b2745fc481c6713fae4f3 |
| https://git.kernel.org/stable/c/21a741eb75f80397e5f7d3739e24d7d75e619011 |
