| 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-2023-52483: mctp: perform route lookups under a RCU read-side lock |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| mctp: perform route lookups under a RCU read-side lock |
| |
| Our current route lookups (mctp_route_lookup and mctp_route_lookup_null) |
| traverse the net's route list without the RCU read lock held. This means |
| the route lookup is subject to preemption, resulting in an potential |
| grace period expiry, and so an eventual kfree() while we still have the |
| route pointer. |
| |
| Add the proper read-side critical section locks around the route |
| lookups, preventing premption and a possible parallel kfree. |
| |
| The remaining net->mctp.routes accesses are already under a |
| rcu_read_lock, or protected by the RTNL for updates. |
| |
| Based on an analysis from Sili Luo <rootlab@huawei.com>, where |
| introducing a delay in the route lookup could cause a UAF on |
| simultaneous sendmsg() and route deletion. |
| |
| The Linux kernel CVE team has assigned CVE-2023-52483 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.15 with commit 889b7da23abf92faf34491df95733bda63639e32 and fixed in 5.15.137 with commit 6c52b12159049046483fdb0c411a0a1869c41a67 |
| Issue introduced in 5.15 with commit 889b7da23abf92faf34491df95733bda63639e32 and fixed in 6.1.59 with commit 1db0724a01b558feb1ecae551782add1951a114a |
| Issue introduced in 5.15 with commit 889b7da23abf92faf34491df95733bda63639e32 and fixed in 6.5.8 with commit 2405f64a95a7a094eb24cba9bcfaffd1ea264de4 |
| Issue introduced in 5.15 with commit 889b7da23abf92faf34491df95733bda63639e32 and fixed in 6.6 with commit 5093bbfc10ab6636b32728e35813cbd79feb063c |
| |
| 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-2023-52483 |
| 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/mctp/route.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/6c52b12159049046483fdb0c411a0a1869c41a67 |
| https://git.kernel.org/stable/c/1db0724a01b558feb1ecae551782add1951a114a |
| https://git.kernel.org/stable/c/2405f64a95a7a094eb24cba9bcfaffd1ea264de4 |
| https://git.kernel.org/stable/c/5093bbfc10ab6636b32728e35813cbd79feb063c |
