| 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-2024-40972: ext4: do not create EA inode under buffer lock |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| ext4: do not create EA inode under buffer lock |
| |
| ext4_xattr_set_entry() creates new EA inodes while holding buffer lock |
| on the external xattr block. This is problematic as it nests all the |
| allocation locking (which acquires locks on other buffers) under the |
| buffer lock. This can even deadlock when the filesystem is corrupted and |
| e.g. quota file is setup to contain xattr block as data block. Move the |
| allocation of EA inode out of ext4_xattr_set_entry() into the callers. |
| |
| The Linux kernel CVE team has assigned CVE-2024-40972 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 6.1.107 with commit 0752e7fb549d90c33b4d4186f11cfd25a556d1dd |
| Fixed in 6.6.47 with commit 737fb7853acd5bc8984f6f42e4bfba3334be8ae1 |
| Fixed in 6.9.7 with commit 111103907234bffd0a34fba070ad9367de058752 |
| Fixed in 6.10 with commit 0a46ef234756dca04623b7591e8ebb3440622f0b |
| |
| 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-2024-40972 |
| 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/ext4/xattr.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/0752e7fb549d90c33b4d4186f11cfd25a556d1dd |
| https://git.kernel.org/stable/c/737fb7853acd5bc8984f6f42e4bfba3334be8ae1 |
| https://git.kernel.org/stable/c/111103907234bffd0a34fba070ad9367de058752 |
| https://git.kernel.org/stable/c/0a46ef234756dca04623b7591e8ebb3440622f0b |
