| 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-2024-27005: interconnect: Don't access req_list while it's being manipulated |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| interconnect: Don't access req_list while it's being manipulated |
| |
| The icc_lock mutex was split into separate icc_lock and icc_bw_lock |
| mutexes in [1] to avoid lockdep splats. However, this didn't adequately |
| protect access to icc_node::req_list. |
| |
| The icc_set_bw() function will eventually iterate over req_list while |
| only holding icc_bw_lock, but req_list can be modified while only |
| holding icc_lock. This causes races between icc_set_bw(), of_icc_get(), |
| and icc_put(). |
| |
| Example A: |
| |
| CPU0 CPU1 |
| ---- ---- |
| icc_set_bw(path_a) |
| mutex_lock(&icc_bw_lock); |
| icc_put(path_b) |
| mutex_lock(&icc_lock); |
| aggregate_requests() |
| hlist_for_each_entry(r, ... |
| hlist_del(... |
| <r = invalid pointer> |
| |
| Example B: |
| |
| CPU0 CPU1 |
| ---- ---- |
| icc_set_bw(path_a) |
| mutex_lock(&icc_bw_lock); |
| path_b = of_icc_get() |
| of_icc_get_by_index() |
| mutex_lock(&icc_lock); |
| path_find() |
| path_init() |
| aggregate_requests() |
| hlist_for_each_entry(r, ... |
| hlist_add_head(... |
| <r = invalid pointer> |
| |
| Fix this by ensuring icc_bw_lock is always held before manipulating |
| icc_node::req_list. The additional places icc_bw_lock is held don't |
| perform any memory allocations, so we should still be safe from the |
| original lockdep splats that motivated the separate locks. |
| |
| [1] commit af42269c3523 ("interconnect: Fix locking for runpm vs reclaim") |
| |
| The Linux kernel CVE team has assigned CVE-2024-27005 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.6 with commit af42269c3523492d71ebbe11fefae2653e9cdc78 and fixed in 6.6.29 with commit d0d04efa2e367921654b5106cc5c05e3757c2b42 |
| Issue introduced in 6.6 with commit af42269c3523492d71ebbe11fefae2653e9cdc78 and fixed in 6.8.8 with commit 4c65507121ea8e0b47fae6d2049c8688390d46b6 |
| Issue introduced in 6.6 with commit af42269c3523492d71ebbe11fefae2653e9cdc78 and fixed in 6.9 with commit de1bf25b6d771abdb52d43546cf57ad775fb68a1 |
| Issue introduced in 6.5.5 with commit 2f3a124696d43de3c837f87a9f767c56ee86cf2a |
| |
| 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-2024-27005 |
| 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: |
| drivers/interconnect/core.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/d0d04efa2e367921654b5106cc5c05e3757c2b42 |
| https://git.kernel.org/stable/c/4c65507121ea8e0b47fae6d2049c8688390d46b6 |
| https://git.kernel.org/stable/c/de1bf25b6d771abdb52d43546cf57ad775fb68a1 |
