| From bippy-1.2.0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@kernel.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2025-39688: nfsd: allow SC_STATUS_FREEABLE when searching via nfs4_lookup_stateid() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| nfsd: allow SC_STATUS_FREEABLE when searching via nfs4_lookup_stateid() |
| |
| The pynfs DELEG8 test fails when run against nfsd. It acquires a |
| delegation and then lets the lease time out. It then tries to use the |
| deleg stateid and expects to see NFS4ERR_DELEG_REVOKED, but it gets |
| bad NFS4ERR_BAD_STATEID instead. |
| |
| When a delegation is revoked, it's initially marked with |
| SC_STATUS_REVOKED, or SC_STATUS_ADMIN_REVOKED and later, it's marked |
| with the SC_STATUS_FREEABLE flag, which denotes that it is waiting for |
| s FREE_STATEID call. |
| |
| nfs4_lookup_stateid() accepts a statusmask that includes the status |
| flags that a found stateid is allowed to have. Currently, that mask |
| never includes SC_STATUS_FREEABLE, which means that revoked delegations |
| are (almost) never found. |
| |
| Add SC_STATUS_FREEABLE to the always-allowed status flags, and remove it |
| from nfsd4_delegreturn() since it's now always implied. |
| |
| The Linux kernel CVE team has assigned CVE-2025-39688 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.12 with commit 8dd91e8d31febf4d9cca3ae1bb4771d33ae7ee5a and fixed in 6.12.23 with commit 52e209203c35a4fbff8af23cd3613efe5df40102 |
| Issue introduced in 6.12 with commit 8dd91e8d31febf4d9cca3ae1bb4771d33ae7ee5a and fixed in 6.13.11 with commit dc6f3295905d7185e71091870119a8c11c3808cc |
| Issue introduced in 6.12 with commit 8dd91e8d31febf4d9cca3ae1bb4771d33ae7ee5a and fixed in 6.14.2 with commit 5bcb44e650bc4ec7eac23df90c5e011a77fa2beb |
| Issue introduced in 6.12 with commit 8dd91e8d31febf4d9cca3ae1bb4771d33ae7ee5a and fixed in 6.15 with commit d1bc15b147d35b4cb7ca99a9a7d79d41ca342c13 |
| Issue introduced in 6.11.6 with commit 967faa26f313a62e7bebc55d5b8122eaee43b929 |
| |
| 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-2025-39688 |
| 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/52e209203c35a4fbff8af23cd3613efe5df40102 |
| https://git.kernel.org/stable/c/dc6f3295905d7185e71091870119a8c11c3808cc |
| https://git.kernel.org/stable/c/5bcb44e650bc4ec7eac23df90c5e011a77fa2beb |
| https://git.kernel.org/stable/c/d1bc15b147d35b4cb7ca99a9a7d79d41ca342c13 |
