| 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-2024-40917: memblock: make memblock_set_node() also warn about use of MAX_NUMNODES |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| memblock: make memblock_set_node() also warn about use of MAX_NUMNODES |
| |
| On an (old) x86 system with SRAT just covering space above 4Gb: |
| |
| ACPI: SRAT: Node 0 PXM 0 [mem 0x100000000-0xfffffffff] hotplug |
| |
| the commit referenced below leads to this NUMA configuration no longer |
| being refused by a CONFIG_NUMA=y kernel (previously |
| |
| NUMA: nodes only cover 6144MB of your 8185MB e820 RAM. Not used. |
| No NUMA configuration found |
| Faking a node at [mem 0x0000000000000000-0x000000027fffffff] |
| |
| was seen in the log directly after the message quoted above), because of |
| memblock_validate_numa_coverage() checking for NUMA_NO_NODE (only). This |
| in turn led to memblock_alloc_range_nid()'s warning about MAX_NUMNODES |
| triggering, followed by a NULL deref in memmap_init() when trying to |
| access node 64's (NODE_SHIFT=6) node data. |
| |
| To compensate said change, make memblock_set_node() warn on and adjust |
| a passed in value of MAX_NUMNODES, just like various other functions |
| already do. |
| |
| The Linux kernel CVE team has assigned CVE-2024-40917 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.6.70 with commit 6fdc770506eb8379bf68a49d4e193c8364ac64e0 and fixed in 6.6.72 with commit 4ddb7f966f3d06fcf1ba5ee298af6714b593584b |
| Issue introduced in 6.8 with commit ff6c3d81f2e86b63a3a530683f89ef393882782a and fixed in 6.9.6 with commit 22f742b8f738918f683198a18ec3c691acda14c4 |
| Issue introduced in 6.8 with commit ff6c3d81f2e86b63a3a530683f89ef393882782a and fixed in 6.10 with commit e0eec24e2e199873f43df99ec39773ad3af2bff7 |
| |
| 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-2024-40917 |
| 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: |
| mm/memblock.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/4ddb7f966f3d06fcf1ba5ee298af6714b593584b |
| https://git.kernel.org/stable/c/22f742b8f738918f683198a18ec3c691acda14c4 |
| https://git.kernel.org/stable/c/e0eec24e2e199873f43df99ec39773ad3af2bff7 |
