| 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-2024-42104: nilfs2: add missing check for inode numbers on directory entries |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| nilfs2: add missing check for inode numbers on directory entries |
| |
| Syzbot reported that mounting and unmounting a specific pattern of |
| corrupted nilfs2 filesystem images causes a use-after-free of metadata |
| file inodes, which triggers a kernel bug in lru_add_fn(). |
| |
| As Jan Kara pointed out, this is because the link count of a metadata file |
| gets corrupted to 0, and nilfs_evict_inode(), which is called from iput(), |
| tries to delete that inode (ifile inode in this case). |
| |
| The inconsistency occurs because directories containing the inode numbers |
| of these metadata files that should not be visible in the namespace are |
| read without checking. |
| |
| Fix this issue by treating the inode numbers of these internal files as |
| errors in the sanity check helper when reading directory folios/pages. |
| |
| Also thanks to Hillf Danton and Matthew Wilcox for their initial mm-layer |
| analysis. |
| |
| The Linux kernel CVE team has assigned CVE-2024-42104 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 4.19.318 with commit c33c2b0d92aa1c2262d999b2598ad6fbd53bd479 |
| Fixed in 5.4.280 with commit 07c176e7acc5579c133bb923ab21316d192d0a95 |
| Fixed in 5.10.222 with commit 2f2fa9cf7c3537958a82fbe8c8595a5eb0861ad7 |
| Fixed in 5.15.163 with commit b11e8fb93ea5eefb2e4e719497ea177a58ff6131 |
| Fixed in 6.1.98 with commit 1b7d549ed2c1fa202c751b69423a0d3a6bd5a180 |
| Fixed in 6.6.39 with commit 3ab40870edb883b9633dc5cd55f5a2a11afa618d |
| Fixed in 6.9.9 with commit 265fff1a01cdc083aeaf0d934c929db5cc64aebf |
| Fixed in 6.10 with commit bb76c6c274683c8570ad788f79d4b875bde0e458 |
| |
| 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-2024-42104 |
| 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/nilfs2/dir.c |
| fs/nilfs2/nilfs.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/c33c2b0d92aa1c2262d999b2598ad6fbd53bd479 |
| https://git.kernel.org/stable/c/07c176e7acc5579c133bb923ab21316d192d0a95 |
| https://git.kernel.org/stable/c/2f2fa9cf7c3537958a82fbe8c8595a5eb0861ad7 |
| https://git.kernel.org/stable/c/b11e8fb93ea5eefb2e4e719497ea177a58ff6131 |
| https://git.kernel.org/stable/c/1b7d549ed2c1fa202c751b69423a0d3a6bd5a180 |
| https://git.kernel.org/stable/c/3ab40870edb883b9633dc5cd55f5a2a11afa618d |
| https://git.kernel.org/stable/c/265fff1a01cdc083aeaf0d934c929db5cc64aebf |
| https://git.kernel.org/stable/c/bb76c6c274683c8570ad788f79d4b875bde0e458 |
