CVE-2024-27023: 
Linux Kernel vulnerability analysis and mitigation

CVE-2024-27023 is a vulnerability in the Linux kernel's MD (Multiple Devices) driver that was discovered and fixed in early 2024. The issue involves a missing release of 'active_io' reference during flush operations in the MD driver. This vulnerability affects the Linux kernel's storage subsystem, specifically the MD RAID functionality (Kernel Git).

The vulnerability stems from a missing release of the 'activeio' reference in the submitflushes() function. When flushpending is decreased to zero, the code fails to properly release the activeio reference, which was obtained during mdflushrequest(). This creates a situation where mddevsuspend() will wait indefinitely for 'activeio' to reach zero, effectively causing a deadlock condition (Kernel Git).

The primary impact of this vulnerability is a potential system hang condition. When the issue occurs, mddevsuspend() will wait forever for 'activeio' to become zero, leading to a deadlock in the system's MD RAID functionality (Kernel Git).

The issue has been fixed by adding proper release of 'activeio' in submitflushes() when 'flush_pending' is decreased to zero. The fix was implemented in the Linux kernel through commit 855678ed8534518e2b428bcbcec695de9ba248e8 and has been backported to stable kernel versions 6.1 and later (Kernel Git).