| 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-2024-50043: nfsd: fix possible badness in FREE_STATEID |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| nfsd: fix possible badness in FREE_STATEID |
| |
| When multiple FREE_STATEIDs are sent for the same delegation stateid, |
| it can lead to a possible either use-after-free or counter refcount |
| underflow errors. |
| |
| In nfsd4_free_stateid() under the client lock we find a delegation |
| stateid, however the code drops the lock before calling nfs4_put_stid(), |
| that allows another FREE_STATE to find the stateid again. The first one |
| will proceed to then free the stateid which leads to either |
| use-after-free or decrementing already zeroed counter. |
| |
| The Linux kernel CVE team has assigned CVE-2024-50043 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.9 with commit 3f29cc82a84c23cfd12b903029dd26002ca825f5 and fixed in 6.11.4 with commit 7ca9e472ce5c67daa3188a348ece8c02a0765039 |
| Issue introduced in 6.9 with commit 3f29cc82a84c23cfd12b903029dd26002ca825f5 and fixed in 6.12 with commit c88c150a467fcb670a1608e2272beeee3e86df6e |
| |
| 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-2024-50043 |
| 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/nfsd/nfs4state.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/7ca9e472ce5c67daa3188a348ece8c02a0765039 |
| https://git.kernel.org/stable/c/c88c150a467fcb670a1608e2272beeee3e86df6e |
