CVE-2026-93123

In the Linux kernel, the following vulnerability has been resolved: serial: qcom-geni: do not advance stale DMA completions The qcom GENI serial DMA TX completion path advances the transmit fifo by the number of bytes recorded in port->tx_remaining. If uart_flush_buffer() runs after the hardware has completed a DMA transfer but before the DMA completion interrupt has been handled, the serial core resets the transmit fifo while port->tx_remaining still describes the old DMA transfer. A previous fix avoided advancing an empty fifo by checking that the fifo length is at least tx_remaining. That still does not distinguish the old DMA payload from new bytes written after the flush. If userspace writes new data before the stale DMA completion interrupt is handled, the fifo can again contain at least tx_remaining bytes and the stale completion can advance and discard those new bytes. Mark an in-flight DMA transfer stale when the transmit fifo is flushed. The later completion still unprepares the original DMA mapping using the saved length, but it no longer advances the transmit fifo.

CVSS

No CVSS.

References

Link	Resource
https://git.kernel.org/stable/c/231c84fe7ec40e4a06c398c0591d5b8e823d68e1
https://git.kernel.org/stable/c/59faa59c25a0a098fbc86275408d7c8405015702
https://git.kernel.org/stable/c/7ea38c49e7178960926657863299face6dc0e1b0
https://git.kernel.org/stable/c/c02d030747c46da33faf406dd772ef91100efa27

Configurations

No configuration.

History

17 Sep 2026, 17:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-17 17:18

Updated : 2026-09-17 17:18

NVD link : CVE-2026-93123

Mitre link : CVE-2026-93123

CVE.ORG link : CVE-2026-93123

JSON object : View

Products Affected

No product.

CWE

No CWE.

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