| From bippy-1.2.0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@kernel.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2021-47374: dma-debug: prevent an error message from causing runtime problems |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| dma-debug: prevent an error message from causing runtime problems |
| |
| For some drivers, that use the DMA API. This error message can be reached |
| several millions of times per second, causing spam to the kernel's printk |
| buffer and bringing the CPU usage up to 100% (so, it should be rate |
| limited). However, since there is at least one driver that is in the |
| mainline and suffers from the error condition, it is more useful to |
| err_printk() here instead of just rate limiting the error message (in hopes |
| that it will make it easier for other drivers that suffer from this issue |
| to be spotted). |
| |
| The Linux kernel CVE team has assigned CVE-2021-47374 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.14 with commit 2b4bbc6231d789f58676d2ccc42177df163e1c4a and fixed in 5.14.9 with commit de4afec2d2946c92c62a15ab341c70b287289e6a |
| Issue introduced in 5.14 with commit 2b4bbc6231d789f58676d2ccc42177df163e1c4a and fixed in 5.15 with commit 510e1a724ab1bf38150be2c1acabb303f98d0047 |
| |
| 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-2021-47374 |
| 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/dma/debug.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/de4afec2d2946c92c62a15ab341c70b287289e6a |
| https://git.kernel.org/stable/c/510e1a724ab1bf38150be2c1acabb303f98d0047 |
