CVE-2026-74655

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description An issue exists in the qcom-geni UART driver where flushing the transmit buffer during an ongoing TX DMA (Direct Memory Access) causes the UART to infinitely repeat corrupted TX DMA frames. This occurs because the DMA-mode uart ops lacks a flush buffer callback, allowing in-flight transfers to complete after the serial core resets the transmit kfifo, which leads to length underflow and indefinite resubmission of page-sized transfers. Additionally, the stop path incorrectly unmapped buffers while the serial engine was still reading them and failed to reset the TX DMA state machine. This can be triggered from userspace by performing a large write followed immediately by TCOFLUSH, causing a subsequent tcdrain to hang indefinitely.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.