| 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-2022-48890: scsi: storvsc: Fix swiotlb bounce buffer leak in confidential VM |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| scsi: storvsc: Fix swiotlb bounce buffer leak in confidential VM |
| |
| storvsc_queuecommand() maps the scatter/gather list using scsi_dma_map(), |
| which in a confidential VM allocates swiotlb bounce buffers. If the I/O |
| submission fails in storvsc_do_io(), the I/O is typically retried by higher |
| level code, but the bounce buffer memory is never freed. The mostly like |
| cause of I/O submission failure is a full VMBus channel ring buffer, which |
| is not uncommon under high I/O loads. Eventually enough bounce buffer |
| memory leaks that the confidential VM can't do any I/O. The same problem |
| can arise in a non-confidential VM with kernel boot parameter |
| swiotlb=force. |
| |
| Fix this by doing scsi_dma_unmap() in the case of an I/O submission |
| error, which frees the bounce buffer memory. |
| |
| The Linux kernel CVE team has assigned CVE-2022-48890 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.17 with commit 743b237c3a7b0f5b44aa704aae8a1058877b6322 and fixed in 6.1.7 with commit 87c71e88f6a6619ffb1ff88f84dff48ef6d57adb |
| Issue introduced in 5.17 with commit 743b237c3a7b0f5b44aa704aae8a1058877b6322 and fixed in 6.2 with commit 67ff3d0a49f3d445c3922e30a54e03c161da561e |
| |
| 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-2022-48890 |
| 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/scsi/storvsc_drv.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/87c71e88f6a6619ffb1ff88f84dff48ef6d57adb |
| https://git.kernel.org/stable/c/67ff3d0a49f3d445c3922e30a54e03c161da561e |
