| From bippy-1.2.0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@kernel.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2024-58093: PCI/ASPM: Fix link state exit during switch upstream function removal |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| PCI/ASPM: Fix link state exit during switch upstream function removal |
| |
| Before 456d8aa37d0f ("PCI/ASPM: Disable ASPM on MFD function removal to |
| avoid use-after-free"), we would free the ASPM link only after the last |
| function on the bus pertaining to the given link was removed. |
| |
| That was too late. If function 0 is removed before sibling function, |
| link->downstream would point to free'd memory after. |
| |
| After above change, we freed the ASPM parent link state upon any function |
| removal on the bus pertaining to a given link. |
| |
| That is too early. If the link is to a PCIe switch with MFD on the upstream |
| port, then removing functions other than 0 first would free a link which |
| still remains parent_link to the remaining downstream ports. |
| |
| The resulting GPFs are especially frequent during hot-unplug, because |
| pciehp removes devices on the link bus in reverse order. |
| |
| On that switch, function 0 is the virtual P2P bridge to the internal bus. |
| Free exactly when function 0 is removed -- before the parent link is |
| obsolete, but after all subordinate links are gone. |
| |
| [kwilczynski: commit log] |
| |
| The Linux kernel CVE team has assigned CVE-2024-58093 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.5 with commit 456d8aa37d0f56fc9e985e812496e861dcd6f2f2 and fixed in 6.15 with commit cbf937dcadfd571a434f8074d057b32cd14fbea5 |
| Issue introduced in 5.4.251 with commit 666e7f9d60cee23077ea3e6331f6f8a19f7ea03f |
| Issue introduced in 5.10.188 with commit 7badf4d6f49a358a01ab072bbff88d3ee886c33b |
| Issue introduced in 5.15.121 with commit 9856c0de49052174ab474113f4ba40c02aaee086 |
| Issue introduced in 6.1.39 with commit 7aecdd47910c51707696e8b0e045b9f88bd4230f |
| Issue introduced in 6.3.13 with commit d51d2eeae4ce54d542909c4d9d07bf371a78592c |
| Issue introduced in 6.4.4 with commit 4203722d51afe3d239e03f15cc73efdf023a7103 |
| |
| 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-2024-58093 |
| 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: |
| drivers/pci/pcie/aspm.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/cbf937dcadfd571a434f8074d057b32cd14fbea5 |
