| 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-2023-52731: fbdev: Fix invalid page access after closing deferred I/O devices |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| fbdev: Fix invalid page access after closing deferred I/O devices |
| |
| When a fbdev with deferred I/O is once opened and closed, the dirty |
| pages still remain queued in the pageref list, and eventually later |
| those may be processed in the delayed work. This may lead to a |
| corruption of pages, hitting an Oops. |
| |
| This patch makes sure to cancel the delayed work and clean up the |
| pageref list at closing the device for addressing the bug. A part of |
| the cleanup code is factored out as a new helper function that is |
| called from the common fb_release(). |
| |
| The Linux kernel CVE team has assigned CVE-2023-52731 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.19 with commit 56c134f7f1b58be08bdb0ca8372474a4a5165f31 and fixed in 6.1.13 with commit f1d91f0e9d5a240a809698d7d9c5a538e7dcc149 |
| Issue introduced in 5.19 with commit 56c134f7f1b58be08bdb0ca8372474a4a5165f31 and fixed in 6.2 with commit 3efc61d95259956db25347e2a9562c3e54546e20 |
| |
| 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-2023-52731 |
| 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/video/fbdev/core/fb_defio.c |
| drivers/video/fbdev/core/fbmem.c |
| include/linux/fb.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/87b9802ca824fcee7915e717e9a60471af62e8e9 |
| https://git.kernel.org/stable/c/f1d91f0e9d5a240a809698d7d9c5a538e7dcc149 |
| https://git.kernel.org/stable/c/3efc61d95259956db25347e2a9562c3e54546e20 |
