| 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-2024-36244: net/sched: taprio: extend minimum interval restriction to entire cycle too |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| net/sched: taprio: extend minimum interval restriction to entire cycle too |
| |
| It is possible for syzbot to side-step the restriction imposed by the |
| blamed commit in the Fixes: tag, because the taprio UAPI permits a |
| cycle-time different from (and potentially shorter than) the sum of |
| entry intervals. |
| |
| We need one more restriction, which is that the cycle time itself must |
| be larger than N * ETH_ZLEN bit times, where N is the number of schedule |
| entries. This restriction needs to apply regardless of whether the cycle |
| time came from the user or was the implicit, auto-calculated value, so |
| we move the existing "cycle == 0" check outside the "if "(!new->cycle_time)" |
| branch. This way covers both conditions and scenarios. |
| |
| Add a selftest which illustrates the issue triggered by syzbot. |
| |
| The Linux kernel CVE team has assigned CVE-2024-36244 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.9 with commit b5b73b26b3ca34574124ed7ae9c5ba8391a7f176 and fixed in 6.1.119 with commit 34d83c3e6e97867ae061d14eb52123404aab1cbc |
| Issue introduced in 5.9 with commit b5b73b26b3ca34574124ed7ae9c5ba8391a7f176 and fixed in 6.6.33 with commit b939d1e04a90248b4cdf417b0969c270ceb992b2 |
| Issue introduced in 5.9 with commit b5b73b26b3ca34574124ed7ae9c5ba8391a7f176 and fixed in 6.9.4 with commit 91f249b01fe490fce11fbb4307952ca8cce78724 |
| Issue introduced in 5.9 with commit b5b73b26b3ca34574124ed7ae9c5ba8391a7f176 and fixed in 6.10 with commit fb66df20a7201e60f2b13d7f95d031b31a8831d3 |
| Issue introduced in 5.4.68 with commit 83bd58952b2b8543d8c48d1453975ab47a0a7504 |
| Issue introduced in 5.8.12 with commit 817ff50796c5e364c879596509f83fcba194bb6f |
| |
| 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-2024-36244 |
| 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/sched/sch_taprio.c |
| tools/testing/selftests/tc-testing/tc-tests/qdiscs/taprio.json |
| |
| |
| 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/34d83c3e6e97867ae061d14eb52123404aab1cbc |
| https://git.kernel.org/stable/c/b939d1e04a90248b4cdf417b0969c270ceb992b2 |
| https://git.kernel.org/stable/c/91f249b01fe490fce11fbb4307952ca8cce78724 |
| https://git.kernel.org/stable/c/fb66df20a7201e60f2b13d7f95d031b31a8831d3 |
