| From bippy-7c5fe7eed585 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-2024-58084: firmware: qcom: scm: Fix missing read barrier in qcom_scm_get_tzmem_pool() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| firmware: qcom: scm: Fix missing read barrier in qcom_scm_get_tzmem_pool() |
| |
| Commit 2e4955167ec5 ("firmware: qcom: scm: Fix __scm and waitq |
| completion variable initialization") introduced a write barrier in probe |
| function to store global '__scm' variable. We all known barriers are |
| paired (see memory-barriers.txt: "Note that write barriers should |
| normally be paired with read or address-dependency barriers"), therefore |
| accessing it from concurrent contexts requires read barrier. Previous |
| commit added such barrier in qcom_scm_is_available(), so let's use that |
| directly. |
| |
| Lack of this read barrier can result in fetching stale '__scm' variable |
| value, NULL, and dereferencing it. |
| |
| Note that barrier in qcom_scm_is_available() satisfies here the control |
| dependency. |
| |
| The Linux kernel CVE team has assigned CVE-2024-58084 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.11 with commit 449d0d84bcd8246b508d07995326d13c54488b8c and fixed in 6.12.14 with commit fee921e3c641f64185abee83f9a6e65f0b380682 |
| Issue introduced in 6.11 with commit 449d0d84bcd8246b508d07995326d13c54488b8c and fixed in 6.13.3 with commit e03db7c1255ebabba5e1a447754faeb138de15a2 |
| Issue introduced in 6.11 with commit 449d0d84bcd8246b508d07995326d13c54488b8c and fixed in 6.14 with commit b628510397b5cafa1f5d3e848a28affd1c635302 |
| |
| 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-2024-58084 |
| 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_scm.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/fee921e3c641f64185abee83f9a6e65f0b380682 |
| https://git.kernel.org/stable/c/e03db7c1255ebabba5e1a447754faeb138de15a2 |
| https://git.kernel.org/stable/c/b628510397b5cafa1f5d3e848a28affd1c635302 |
