| 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-2021-47604: vduse: check that offset is within bounds in get_config() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| vduse: check that offset is within bounds in get_config() |
| |
| This condition checks "len" but it does not check "offset" and that |
| could result in an out of bounds read if "offset > dev->config_size". |
| The problem is that since both variables are unsigned the |
| "dev->config_size - offset" subtraction would result in a very high |
| unsigned value. |
| |
| I think these checks might not be necessary because "len" and "offset" |
| are supposed to already have been validated using the |
| vhost_vdpa_config_validate() function. But I do not know the code |
| perfectly, and I like to be safe. |
| |
| The Linux kernel CVE team has assigned CVE-2021-47604 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.15 with commit c8a6153b6c59d95c0e091f053f6f180952ade91e and fixed in 5.15.11 with commit ebbbc5fea3f648175df1aa3f127c78eb0252cc2a |
| Issue introduced in 5.15 with commit c8a6153b6c59d95c0e091f053f6f180952ade91e and fixed in 5.16 with commit dc1db0060c02d119fd4196924eff2d1129e9a442 |
| |
| 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-2021-47604 |
| 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/vdpa/vdpa_user/vduse_dev.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/ebbbc5fea3f648175df1aa3f127c78eb0252cc2a |
| https://git.kernel.org/stable/c/dc1db0060c02d119fd4196924eff2d1129e9a442 |
