| 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-2021-47382: s390/qeth: fix deadlock during failing recovery |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| s390/qeth: fix deadlock during failing recovery |
| |
| Commit 0b9902c1fcc5 ("s390/qeth: fix deadlock during recovery") removed |
| taking discipline_mutex inside qeth_do_reset(), fixing potential |
| deadlocks. An error path was missed though, that still takes |
| discipline_mutex and thus has the original deadlock potential. |
| |
| Intermittent deadlocks were seen when a qeth channel path is configured |
| offline, causing a race between qeth_do_reset and ccwgroup_remove. |
| Call qeth_set_offline() directly in the qeth_do_reset() error case and |
| then a new variant of ccwgroup_set_offline(), without taking |
| discipline_mutex. |
| |
| The Linux kernel CVE team has assigned CVE-2021-47382 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.11 with commit b41b554c1ee75070a14c02a88496b1f231c7eacc and fixed in 5.14.10 with commit 0bfe741741327822d1482c7edef0184636d08b40 |
| Issue introduced in 5.11 with commit b41b554c1ee75070a14c02a88496b1f231c7eacc and fixed in 5.15 with commit d2b59bd4b06d84a4eadb520b0f71c62fe8ec0a62 |
| Issue introduced in 5.10.8 with commit af0c184ea106051e428b5a0b5f2dfd31cbc54c52 |
| |
| 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-2021-47382 |
| 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: |
| arch/s390/include/asm/ccwgroup.h |
| drivers/s390/cio/ccwgroup.c |
| drivers/s390/net/qeth_core_main.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/0bfe741741327822d1482c7edef0184636d08b40 |
| https://git.kernel.org/stable/c/d2b59bd4b06d84a4eadb520b0f71c62fe8ec0a62 |
