Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
md: fix soft lockup in status_resync
status_resync() will calculate ‘curr_resync - recovery_active’ to show user a progress bar like following:
[============>……..] resync = 61.4%
‘curr_resync’ and ‘recovery_active’ is updated in md_do_sync(), and status_resync() can read them concurrently, hence it’s possible that ‘curr_resync - recovery_active’ can overflow to a huge number. In this case status_resync() will be stuck in the loop to print a large amount of ‘=’, which will end up soft lockup.
Fix the problem by setting ‘resync’ to MD_RESYNC_ACTIVE in this case, this way resync in progress will be reported to user.
Details
- Affected product:
- AlmaLinux 9.2 ESU , CentOS 6 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , CloudLinux 7 ELS , Oracle Linux 6 ELS , Oracle Linux 7 ELS , RHEL 7 ELS , TuxCare 9.6 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- linux-hwe @ 4.15.0 (+15 more)
In the Linux kernel, the following vulnerability has been resolved:
md: fix soft lockup in status_resync
status_resync() will calculate ‘curr_resync - recovery_active’ to show user a progress bar like following:
[============>……..] resync = 61.4%
‘curr_resync’ and ‘recovery_active’ is updated in md_do_sync(), and status_resync() can read them concurrently, hence it’s possible that ‘curr_resync - recovery_active’ can overflow to a huge number. In this case status_resync() will be stuck in the loop to print a large amount of ‘=’, which will end up soft lockup.
Fix the problem by setting ‘resync’ to MD_RESYNC_ACTIVE in this case, this way resync in progress will be reported to user.