Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: serial: qcom-geni: fix TX DMA buffer flush When transmit flushing a qcom-geni UART during an ongoing TX DMA, the UART gets stuck infinitely repeating corrupted TX DMA frames. The DMA-mode uart_ops does not provide a flush_buffer callback, so an in-flight transfer can complete after serial core has reset the transmit kfifo, underflowing its length and resubmitting page-sized transfers indefinitely. Add one that stops the transfer and clears tx_remaining and tx_queued. The stop path was also broken: it unmapped the buffer while the serial engine could still read it, and never reset the TX DMA state machine. Cancel the main sequencer command first, then reset the state machine and wait for it before unmapping. Drop the early return so a pending mapping is also cleaned up when the main command is inactive. The bug can be triggered from userspace with a large write immediately followed by TCOFLUSH. A following tcdrain will hang forever. The bug was reproduced and this fix was validated on Arduino Uno Q (QRB2210) using /dev/ttyHS1.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 2aaa43c7077833301c237684cd7bc9ae5e3dec95 before 1606abb7ce8c0cfef98c7e556b83c14e5d73c1bf; affected 2aaa43c7077833301c237684cd7bc9ae5e3dec95 before 313ae287442e5e8d3f7b53b73f37d384bda072d0; affected 2aaa43c7077833301c237684cd7bc9ae5e3dec95 before 1c31e2377f4c1bb110ca7f6e597b2253a7440c37; affected 2aaa43c7077833301c237684cd7bc9ae5e3dec95 before b1801c0d40f62778b613334de5840aba10a564d5; affected 2aaa43c7077833301c237684cd7bc9ae5e3dec95 before e3c04834ae1ab5e9cfbe8ac54ec734aa4774249d |
| Linux / Linux | affected 6.3; unaffected 0 before 6.3; unaffected 6.6.154 through 6.6.*; unaffected 6.12.104 through 6.12.*; unaffected 6.18.45 through 6.18.*; unaffected 7.1.9 through 7.1.*; unaffected 7.2 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/1606abb7ce8c0cfef98c7e556b83c14e5d73c1bf
- https://git.kernel.org/stable/c/313ae287442e5e8d3f7b53b73f37d384bda072d0
- https://git.kernel.org/stable/c/1c31e2377f4c1bb110ca7f6e597b2253a7440c37
- https://git.kernel.org/stable/c/b1801c0d40f62778b613334de5840aba10a564d5
- https://git.kernel.org/stable/c/e3c04834ae1ab5e9cfbe8ac54ec734aa4774249d