| 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-2024-57875: block: RCU protect disk->conv_zones_bitmap |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| block: RCU protect disk->conv_zones_bitmap |
| |
| Ensure that a disk revalidation changing the conventional zones bitmap |
| of a disk does not cause invalid memory references when using the |
| disk_zone_is_conv() helper by RCU protecting the disk->conv_zones_bitmap |
| pointer. |
| |
| disk_zone_is_conv() is modified to operate under the RCU read lock and |
| the function disk_set_conv_zones_bitmap() is added to update a disk |
| conv_zones_bitmap pointer using rcu_replace_pointer() with the disk |
| zone_wplugs_lock spinlock held. |
| |
| disk_free_zone_resources() is modified to call |
| disk_update_zone_resources() with a NULL bitmap pointer to free the disk |
| conv_zones_bitmap. disk_set_conv_zones_bitmap() is also used in |
| disk_update_zone_resources() to set the new (revalidated) bitmap and |
| free the old one. |
| |
| The Linux kernel CVE team has assigned CVE-2024-57875 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 6.12.5 with commit 493326c4f10cc71a42c27fdc97ce112182ee4cbc |
| Fixed in 6.13 with commit d7cb6d7414ea1b33536fa6d11805cb8dceec1f97 |
| |
| 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-2024-57875 |
| 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: |
| block/blk-zoned.c |
| include/linux/blkdev.h |
| |
| |
| 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/493326c4f10cc71a42c27fdc97ce112182ee4cbc |
| https://git.kernel.org/stable/c/d7cb6d7414ea1b33536fa6d11805cb8dceec1f97 |
