| 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-2021-47123: io_uring: fix ltout double free on completion race |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| io_uring: fix ltout double free on completion race |
| |
| Always remove linked timeout on io_link_timeout_fn() from the master |
| request link list, otherwise we may get use-after-free when first |
| io_link_timeout_fn() puts linked timeout in the fail path, and then |
| will be found and put on master's free. |
| |
| The Linux kernel CVE team has assigned CVE-2021-47123 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.11 with commit 90cd7e424969d29aff653333b4dcb4e2e199d791 and fixed in 5.12.10 with commit 1f64f5e903b9d1d157875721e02adadc9d6f0a5d |
| Issue introduced in 5.11 with commit 90cd7e424969d29aff653333b4dcb4e2e199d791 and fixed in 5.13 with commit 447c19f3b5074409c794b350b10306e1da1ef4ba |
| |
| 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-2021-47123 |
| 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: |
| fs/io_uring.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/1f64f5e903b9d1d157875721e02adadc9d6f0a5d |
| https://git.kernel.org/stable/c/447c19f3b5074409c794b350b10306e1da1ef4ba |
