An issue was discovered in writetptentry in drivers/infiniband/hw/cxgb4/mem.c in the Linux kernel through 5.3.2. The cxgb4 driver is directly calling dmamapsingle (a DMA function) from a stack variable. This could allow an attacker to trigger a Denial of Service, exploitable if this driver is used on an architecture for which this stack/DMA interaction has security relevance.