Description
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.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
2aaa43c7077833301c237684cd7bc9ae5e3dec95 to < 231c84fe7ec40e4a06c398c0591d5b8e823d68e1affected2aaa43c7077833301c237684cd7bc9ae5e3dec95 to < c02d030747c46da33faf406dd772ef91100efa27affected2aaa43c7077833301c237684cd7bc9ae5e3dec95 to < 59faa59c25a0a098fbc86275408d7c8405015702affected2aaa43c7077833301c237684cd7bc9ae5e3dec95 to < 7ea38c49e7178960926657863299face6dc0e1b0affected
Linux Linux
Default version status: affected
6.3affected0 to < 6.3unaffected6.12.110 to ≤ 6.12.*unaffected6.18.52 to ≤ 6.18.*unaffected7.2.6 to ≤ 7.2.*unaffected7.3 to ≤ *unaffected