| 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-2024-42105: nilfs2: fix inode number range checks |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| nilfs2: fix inode number range checks |
| |
| Patch series "nilfs2: fix potential issues related to reserved inodes". |
| |
| This series fixes one use-after-free issue reported by syzbot, caused by |
| nilfs2's internal inode being exposed in the namespace on a corrupted |
| filesystem, and a couple of flaws that cause problems if the starting |
| number of non-reserved inodes written in the on-disk super block is |
| intentionally (or corruptly) changed from its default value. |
| |
| |
| This patch (of 3): |
| |
| In the current implementation of nilfs2, "nilfs->ns_first_ino", which |
| gives the first non-reserved inode number, is read from the superblock, |
| but its lower limit is not checked. |
| |
| As a result, if a number that overlaps with the inode number range of |
| reserved inodes such as the root directory or metadata files is set in the |
| super block parameter, the inode number test macros (NILFS_MDT_INODE and |
| NILFS_VALID_INODE) will not function properly. |
| |
| In addition, these test macros use left bit-shift calculations using with |
| the inode number as the shift count via the BIT macro, but the result of a |
| shift calculation that exceeds the bit width of an integer is undefined in |
| the C specification, so if "ns_first_ino" is set to a large value other |
| than the default value NILFS_USER_INO (=11), the macros may potentially |
| malfunction depending on the environment. |
| |
| Fix these issues by checking the lower bound of "nilfs->ns_first_ino" and |
| by preventing bit shifts equal to or greater than the NILFS_USER_INO |
| constant in the inode number test macros. |
| |
| Also, change the type of "ns_first_ino" from signed integer to unsigned |
| integer to avoid the need for type casting in comparisons such as the |
| lower bound check introduced this time. |
| |
| The Linux kernel CVE team has assigned CVE-2024-42105 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 4.19.318 with commit 57235c3c88bb430043728d0d02f44a4efe386476 |
| Fixed in 5.4.280 with commit 08cab183a624ba71603f3754643ae11cab34dbc4 |
| Fixed in 5.10.222 with commit 731011ac6c37cbe97ece229fc6daa486276052c5 |
| Fixed in 5.15.163 with commit 3be4dcc8d7bea52ea41f87aa4bbf959efe7a5987 |
| Fixed in 6.1.98 with commit fae1959d6ab2c52677b113935e36ab4e25df37ea |
| Fixed in 6.6.39 with commit 9194f8ca57527958bee207919458e372d638d783 |
| Fixed in 6.9.9 with commit 1c91058425a01131ea30dda6cf43c67b17884d6a |
| Fixed in 6.10 with commit e2fec219a36e0993642844be0f345513507031f4 |
| |
| 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-2024-42105 |
| 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/nilfs.h |
| fs/nilfs2/the_nilfs.c |
| fs/nilfs2/the_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/57235c3c88bb430043728d0d02f44a4efe386476 |
| https://git.kernel.org/stable/c/08cab183a624ba71603f3754643ae11cab34dbc4 |
| https://git.kernel.org/stable/c/731011ac6c37cbe97ece229fc6daa486276052c5 |
| https://git.kernel.org/stable/c/3be4dcc8d7bea52ea41f87aa4bbf959efe7a5987 |
| https://git.kernel.org/stable/c/fae1959d6ab2c52677b113935e36ab4e25df37ea |
| https://git.kernel.org/stable/c/9194f8ca57527958bee207919458e372d638d783 |
| https://git.kernel.org/stable/c/1c91058425a01131ea30dda6cf43c67b17884d6a |
| https://git.kernel.org/stable/c/e2fec219a36e0993642844be0f345513507031f4 |
