| 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-2025-21636: sctp: sysctl: plpmtud_probe_interval: avoid using current->nsproxy |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| sctp: sysctl: plpmtud_probe_interval: avoid using current->nsproxy |
| |
| As mentioned in a previous commit of this series, using the 'net' |
| structure via 'current' is not recommended for different reasons: |
| |
| - Inconsistency: getting info from the reader's/writer's netns vs only |
| from the opener's netns. |
| |
| - current->nsproxy can be NULL in some cases, resulting in an 'Oops' |
| (null-ptr-deref), e.g. when the current task is exiting, as spotted by |
| syzbot [1] using acct(2). |
| |
| The 'net' structure can be obtained from the table->data using |
| container_of(). |
| |
| Note that table->data could also be used directly, as this is the only |
| member needed from the 'net' structure, but that would increase the size |
| of this fix, to use '*data' everywhere 'net->sctp.probe_interval' is |
| used. |
| |
| The Linux kernel CVE team has assigned CVE-2025-21636 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.14 with commit d1e462a7a5f359cbb9a0e8fbfafcfb6657034105 and fixed in 5.15.177 with commit 1dc5da6c4178f3e4b95c631418f72de9f86c0449 |
| Issue introduced in 5.14 with commit d1e462a7a5f359cbb9a0e8fbfafcfb6657034105 and fixed in 6.1.125 with commit 44ee8635922b6eb940faddb961a8347c6857d722 |
| Issue introduced in 5.14 with commit d1e462a7a5f359cbb9a0e8fbfafcfb6657034105 and fixed in 6.6.72 with commit 284a221f8fa503628432c7bb5108277c688c6ffa |
| Issue introduced in 5.14 with commit d1e462a7a5f359cbb9a0e8fbfafcfb6657034105 and fixed in 6.12.10 with commit bcf8c60074e81ed2ac2d35130917175a3949c917 |
| Issue introduced in 5.14 with commit d1e462a7a5f359cbb9a0e8fbfafcfb6657034105 and fixed in 6.13 with commit 6259d2484d0ceff42245d1f09cc8cb6ee72d847a |
| |
| 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-2025-21636 |
| 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: |
| net/sctp/sysctl.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/1dc5da6c4178f3e4b95c631418f72de9f86c0449 |
| https://git.kernel.org/stable/c/44ee8635922b6eb940faddb961a8347c6857d722 |
| https://git.kernel.org/stable/c/284a221f8fa503628432c7bb5108277c688c6ffa |
| https://git.kernel.org/stable/c/bcf8c60074e81ed2ac2d35130917175a3949c917 |
| https://git.kernel.org/stable/c/6259d2484d0ceff42245d1f09cc8cb6ee72d847a |
