| 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-2025-37879: 9p/net: fix improper handling of bogus negative read/write replies |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| 9p/net: fix improper handling of bogus negative read/write replies |
| |
| In p9_client_write() and p9_client_read_once(), if the server |
| incorrectly replies with success but a negative write/read count then we |
| would consider written (negative) <= rsize (positive) because both |
| variables were signed. |
| |
| Make variables unsigned to avoid this problem. |
| |
| The reproducer linked below now fails with the following error instead |
| of a null pointer deref: |
| 9pnet: bogus RWRITE count (4294967295 > 3) |
| |
| The Linux kernel CVE team has assigned CVE-2025-37879 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 6.1.136 with commit 468ff4a7c61fb811c596a7c44b6a5455e40fd12b |
| Fixed in 6.6.89 with commit a68768e280b7d0c967ea509e791bb9b90adc94a5 |
| Fixed in 6.12.26 with commit c548f95688e2b5ae0e2ae43d53cf717156c7d034 |
| Fixed in 6.14.5 with commit 374e4cd75617c8c2552f562f39dd989583f5c330 |
| Fixed in 6.15 with commit d0259a856afca31d699b706ed5e2adf11086c73b |
| |
| 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-2025-37879 |
| 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/9p/client.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/468ff4a7c61fb811c596a7c44b6a5455e40fd12b |
| https://git.kernel.org/stable/c/a68768e280b7d0c967ea509e791bb9b90adc94a5 |
| https://git.kernel.org/stable/c/c548f95688e2b5ae0e2ae43d53cf717156c7d034 |
| https://git.kernel.org/stable/c/374e4cd75617c8c2552f562f39dd989583f5c330 |
| https://git.kernel.org/stable/c/d0259a856afca31d699b706ed5e2adf11086c73b |
