Race Condition in Linux Kernel io_uring's Message Ring Allocation

CVE-2025-38453

What is CVE-2025-38453?

A race condition vulnerability exists in the Linux Kernel's io_uring subsystem, particularly within the message ring's allocation and deallocation process. The issue arises when requests are simultaneously allocated and freed without proper synchronization, leading to potential data integrity problems. This situation can trigger an illegal access to a freed memory space, which could be exploited if left unaddressed. The vulnerability has been mitigated by implementing deferred freeing mechanisms to enhance safety in resource management. Proper synchronization measures using kfree_rcu() ensure that requests remain allocated during critical execution phases, decreasing the likelihood of erratic behavior under concurrent conditions.

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