CVE-2024-47143

Name of the Vulnerable Software and Affected Versions: Linux kernel versions prior to 6.6.74

Description: A possible deadlock scenario can occur when the dma debug API is called while holding rq lock(). This happens because radix lock() is held while holding dma hash entry[idx].lock. The situation can arise in two ways: when extending the radix tree and trying to wake up kswapd via wake all kswapd(), or when a dma sync operation is called while deleting perf event using etm and etr tmc, which are Arm Coresight hwtracing driver backends.

Recommendations: To resolve the issue, update to Linux kernel version 6.6.74 or later. As a temporary workaround, consider modifying the check unmap() function to call dma entry free() after put hash bucket() to avoid the possible deadlock scenario.