DMA Transaction Management Issue in Linux Kernel Affects 8250 Serial Driver

CVE-2026-43061

What is CVE-2026-43061?

A vulnerability in the Linux kernel's 8250 serial driver has been identified that affects direct memory access (DMA) transaction management. When using DMA, the dmaengine_terminate_async function does not ensure the execution of the __dma_tx_complete callback, which is crucial for clearing the dma->tx_running state. If the transaction is halted and this callback does not execute, it results in a persistent state where new TX DMA transactions cannot be initiated. The recent fix ensures that the dma->tx_running flag is cleared upon the termination of a DMA transaction, thus allowing for proper management of subsequent transactions.

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