CVE-2024-26962

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

dm-raid456, md/raid456: fix a deadlock for dm-raid456 while io concurrent with reshape

For raid456, if reshape is still in progress, then IO across reshape

position will wait for reshape to make progress. However, for dm-raid,

in following cases reshape will never make progress hence IO will hang:

1) the array is read-only;

2) MD_RECOVERY_WAIT is set;

3) MD_RECOVERY_FROZEN is set;

After commit c467e97f079f ("md/raid6: use valid sector values to determine

if an I/O should wait on the reshape") fix the problem that IO across

reshape position doesn't wait for reshape, the dm-raid test

shell/lvconvert-raid-reshape.sh start to hang:

[root@fedora ~]# cat /proc/979/stack

[<0>] wait_woken+0x7d/0x90

[<0>] raid5_make_request+0x929/0x1d70 [raid456]

[<0>] md_handle_request+0xc2/0x3b0 [md_mod]

[<0>] raid_map+0x2c/0x50 [dm_raid]

[<0>] __map_bio+0x251/0x380 [dm_mod]

[<0>] dm_submit_bio+0x1f0/0x760 [dm_mod]

[<0>] __submit_bio+0xc

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References