| 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-2024-26689: ceph: prevent use-after-free in encode_cap_msg() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| ceph: prevent use-after-free in encode_cap_msg() |
| |
| In fs/ceph/caps.c, in encode_cap_msg(), "use after free" error was |
| caught by KASAN at this line - 'ceph_buffer_get(arg->xattr_buf);'. This |
| implies before the refcount could be increment here, it was freed. |
| |
| In same file, in "handle_cap_grant()" refcount is decremented by this |
| line - 'ceph_buffer_put(ci->i_xattrs.blob);'. It appears that a race |
| occurred and resource was freed by the latter line before the former |
| line could increment it. |
| |
| encode_cap_msg() is called by __send_cap() and __send_cap() is called by |
| ceph_check_caps() after calling __prep_cap(). __prep_cap() is where |
| arg->xattr_buf is assigned to ci->i_xattrs.blob. This is the spot where |
| the refcount must be increased to prevent "use after free" error. |
| |
| The Linux kernel CVE team has assigned CVE-2024-26689 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 2.6.34 with commit 9030aaf9bf0a1eee47a154c316c789e959638b0f and fixed in 5.10.210 with commit 8180d0c27b93a6eb60da1b08ea079e3926328214 |
| Issue introduced in 2.6.34 with commit 9030aaf9bf0a1eee47a154c316c789e959638b0f and fixed in 5.15.149 with commit 70e329b440762390258a6fe8c0de93c9fdd56c77 |
| Issue introduced in 2.6.34 with commit 9030aaf9bf0a1eee47a154c316c789e959638b0f and fixed in 6.1.79 with commit f3f98d7d84b31828004545e29fd7262b9f444139 |
| Issue introduced in 2.6.34 with commit 9030aaf9bf0a1eee47a154c316c789e959638b0f and fixed in 6.6.18 with commit ae20db45e482303a20e56f2db667a9d9c54ac7e7 |
| Issue introduced in 2.6.34 with commit 9030aaf9bf0a1eee47a154c316c789e959638b0f and fixed in 6.7.6 with commit 7958c1bf5b03c6f1f58e724dbdec93f8f60b96fc |
| Issue introduced in 2.6.34 with commit 9030aaf9bf0a1eee47a154c316c789e959638b0f and fixed in 6.8 with commit cda4672da1c26835dcbd7aec2bfed954eda9b5ef |
| |
| 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-2024-26689 |
| 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/ceph/caps.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/8180d0c27b93a6eb60da1b08ea079e3926328214 |
| https://git.kernel.org/stable/c/70e329b440762390258a6fe8c0de93c9fdd56c77 |
| https://git.kernel.org/stable/c/f3f98d7d84b31828004545e29fd7262b9f444139 |
| https://git.kernel.org/stable/c/ae20db45e482303a20e56f2db667a9d9c54ac7e7 |
| https://git.kernel.org/stable/c/7958c1bf5b03c6f1f58e724dbdec93f8f60b96fc |
| https://git.kernel.org/stable/c/cda4672da1c26835dcbd7aec2bfed954eda9b5ef |
