| 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-2024-41013: xfs: don't walk off the end of a directory data block |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| xfs: don't walk off the end of a directory data block |
| |
| This adds sanity checks for xfs_dir2_data_unused and xfs_dir2_data_entry |
| to make sure don't stray beyond valid memory region. Before patching, the |
| loop simply checks that the start offset of the dup and dep is within the |
| range. So in a crafted image, if last entry is xfs_dir2_data_unused, we |
| can change dup->length to dup->length-1 and leave 1 byte of space. In the |
| next traversal, this space will be considered as dup or dep. We may |
| encounter an out of bound read when accessing the fixed members. |
| |
| In the patch, we make sure that the remaining bytes large enough to hold |
| an unused entry before accessing xfs_dir2_data_unused and |
| xfs_dir2_data_unused is XFS_DIR2_DATA_ALIGN byte aligned. We also make |
| sure that the remaining bytes large enough to hold a dirent with a |
| single-byte name before accessing xfs_dir2_data_entry. |
| |
| The Linux kernel CVE team has assigned CVE-2024-41013 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 6.6.68 with commit ca96d83c93071f95cf962ce92406621a472df31b |
| Fixed in 6.11 with commit 0c7fcdb6d06cdf8b19b57c17605215b06afa864a |
| |
| 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-2024-41013 |
| 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: |
| fs/xfs/libxfs/xfs_dir2_data.c |
| fs/xfs/libxfs/xfs_dir2_priv.h |
| |
| |
| 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/ca96d83c93071f95cf962ce92406621a472df31b |
| https://git.kernel.org/stable/c/0c7fcdb6d06cdf8b19b57c17605215b06afa864a |
