| 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-2021-47088: mm/damon/dbgfs: protect targets destructions with kdamond_lock |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| mm/damon/dbgfs: protect targets destructions with kdamond_lock |
| |
| DAMON debugfs interface iterates current monitoring targets in |
| 'dbgfs_target_ids_read()' while holding the corresponding |
| 'kdamond_lock'. However, it also destructs the monitoring targets in |
| 'dbgfs_before_terminate()' without holding the lock. This can result in |
| a use_after_free bug. This commit avoids the race by protecting the |
| destruction with the corresponding 'kdamond_lock'. |
| |
| The Linux kernel CVE team has assigned CVE-2021-47088 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.15 with commit 4bc05954d0076655cfaf6f0135585bdc20cd6b11 and fixed in 5.15.12 with commit 330c6117a82c16a9a365a51cec5c9ab30b13245c |
| Issue introduced in 5.15 with commit 4bc05954d0076655cfaf6f0135585bdc20cd6b11 and fixed in 5.16 with commit 34796417964b8d0aef45a99cf6c2d20cebe33733 |
| |
| 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-2021-47088 |
| 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: |
| mm/damon/dbgfs.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/330c6117a82c16a9a365a51cec5c9ab30b13245c |
| https://git.kernel.org/stable/c/34796417964b8d0aef45a99cf6c2d20cebe33733 |
