| 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-2025-21837: io_uring/uring_cmd: unconditionally copy SQEs at prep time |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| io_uring/uring_cmd: unconditionally copy SQEs at prep time |
| |
| This isn't generally necessary, but conditions have been observed where |
| SQE data is accessed from the original SQE after prep has been done and |
| outside of the initial issue. Opcode prep handlers must ensure that any |
| SQE related data is stable beyond the prep phase, but uring_cmd is a bit |
| special in how it handles the SQE which makes it susceptible to reading |
| stale data. If the application has reused the SQE before the original |
| completes, then that can lead to data corruption. |
| |
| Down the line we can relax this again once uring_cmd has been sanitized |
| a bit, and avoid unnecessarily copying the SQE. |
| |
| The Linux kernel CVE team has assigned CVE-2025-21837 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.10 with commit 5eff57fa9f3aae3acbcaf196af507eec58955f3b and fixed in 6.13.4 with commit 87fe1d68842a308998b315c8ed0163a1d639017c |
| Issue introduced in 6.10 with commit 5eff57fa9f3aae3acbcaf196af507eec58955f3b and fixed in 6.14 with commit d6211ebbdaa541af197b50b8dd8f22642ce0b87f |
| |
| 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-2025-21837 |
| 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: |
| io_uring/uring_cmd.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/87fe1d68842a308998b315c8ed0163a1d639017c |
| https://git.kernel.org/stable/c/d6211ebbdaa541af197b50b8dd8f22642ce0b87f |
