| 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-2024-35994: firmware: qcom: uefisecapp: Fix memory related IO errors and crashes |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| firmware: qcom: uefisecapp: Fix memory related IO errors and crashes |
| |
| It turns out that while the QSEECOM APP_SEND command has specific fields |
| for request and response buffers, uefisecapp expects them both to be in |
| a single memory region. Failure to adhere to this has (so far) resulted |
| in either no response being written to the response buffer (causing an |
| EIO to be emitted down the line), the SCM call to fail with EINVAL |
| (i.e., directly from TZ/firmware), or the device to be hard-reset. |
| |
| While this issue can be triggered deterministically, in the current form |
| it seems to happen rather sporadically (which is why it has gone |
| unnoticed during earlier testing). This is likely due to the two |
| kzalloc() calls (for request and response) being directly after each |
| other. Which means that those likely return consecutive regions most of |
| the time, especially when not much else is going on in the system. |
| |
| Fix this by allocating a single memory region for both request and |
| response buffers, properly aligning both structs inside it. This |
| unfortunately also means that the qcom_scm_qseecom_app_send() interface |
| needs to be restructured, as it should no longer map the DMA regions |
| separately. Therefore, move the responsibility of DMA allocation (or |
| mapping) to the caller. |
| |
| The Linux kernel CVE team has assigned CVE-2024-35994 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.7 with commit 759e7a2b62eb3ef3c93ffeb5cca788a09627d7d9 and fixed in 6.8.9 with commit dd22b34fb53cb04b13b2f5eee5c9200bb091fc88 |
| Issue introduced in 6.7 with commit 759e7a2b62eb3ef3c93ffeb5cca788a09627d7d9 and fixed in 6.9 with commit ed09f81eeaa8f9265e1787282cb283f10285c259 |
| |
| 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-2024-35994 |
| 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/firmware/qcom/qcom_qseecom_uefisecapp.c |
| drivers/firmware/qcom/qcom_scm.c |
| include/linux/firmware/qcom/qcom_qseecom.h |
| include/linux/firmware/qcom/qcom_scm.h |
| |
| |
| 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/dd22b34fb53cb04b13b2f5eee5c9200bb091fc88 |
| https://git.kernel.org/stable/c/ed09f81eeaa8f9265e1787282cb283f10285c259 |
