| 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-2023-52836: locking/ww_mutex/test: Fix potential workqueue corruption |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| locking/ww_mutex/test: Fix potential workqueue corruption |
| |
| In some cases running with the test-ww_mutex code, I was seeing |
| odd behavior where sometimes it seemed flush_workqueue was |
| returning before all the work threads were finished. |
| |
| Often this would cause strange crashes as the mutexes would be |
| freed while they were being used. |
| |
| Looking at the code, there is a lifetime problem as the |
| controlling thread that spawns the work allocates the |
| "struct stress" structures that are passed to the workqueue |
| threads. Then when the workqueue threads are finished, |
| they free the stress struct that was passed to them. |
| |
| Unfortunately the workqueue work_struct node is in the stress |
| struct. Which means the work_struct is freed before the work |
| thread returns and while flush_workqueue is waiting. |
| |
| It seems like a better idea to have the controlling thread |
| both allocate and free the stress structures, so that we can |
| be sure we don't corrupt the workqueue by freeing the structure |
| prematurely. |
| |
| So this patch reworks the test to do so, and with this change |
| I no longer see the early flush_workqueue returns. |
| |
| The Linux kernel CVE team has assigned CVE-2023-52836 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 4.14.331 with commit d4d37c9e6a4dbcca958dabd99216550525c7e389 |
| Fixed in 4.19.300 with commit d8267cabbe1bed15ccf8b0e684c528bf8eeef715 |
| Fixed in 5.4.262 with commit dcd85e3c929368076a7592b27f541e0da8b427f5 |
| Fixed in 5.10.202 with commit 9ed2d68b3925145f5f51c46559484881d6082f75 |
| Fixed in 5.15.140 with commit e89d0ed45a419c485bae999426ecf92697cbdda3 |
| Fixed in 6.1.64 with commit c56df79d68677cf062da1b6e3b33e74299a92dfc |
| Fixed in 6.5.13 with commit e36407713163363e65566e7af0abe207d5f59a0c |
| Fixed in 6.6.3 with commit 304a2c4aad0fff887ce493e4197bf9cbaf394479 |
| Fixed in 6.7 with commit bccdd808902f8c677317cec47c306e42b93b849e |
| |
| 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-2023-52836 |
| 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: |
| kernel/locking/test-ww_mutex.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/d4d37c9e6a4dbcca958dabd99216550525c7e389 |
| https://git.kernel.org/stable/c/d8267cabbe1bed15ccf8b0e684c528bf8eeef715 |
| https://git.kernel.org/stable/c/dcd85e3c929368076a7592b27f541e0da8b427f5 |
| https://git.kernel.org/stable/c/9ed2d68b3925145f5f51c46559484881d6082f75 |
| https://git.kernel.org/stable/c/e89d0ed45a419c485bae999426ecf92697cbdda3 |
| https://git.kernel.org/stable/c/c56df79d68677cf062da1b6e3b33e74299a92dfc |
| https://git.kernel.org/stable/c/e36407713163363e65566e7af0abe207d5f59a0c |
| https://git.kernel.org/stable/c/304a2c4aad0fff887ce493e4197bf9cbaf394479 |
| https://git.kernel.org/stable/c/bccdd808902f8c677317cec47c306e42b93b849e |
