On 22.02.2023 15:50, Krzysztof Kozlowski wrote:
On 22/02/2023 15:47, Konrad Dybcio wrote:
On 22.02.2023 15:44, Krzysztof Kozlowski wrote:
There are two issues related to the number of ports coming from Devicetree when exceeding in total QCOM_SDW_MAX_PORTS. Both lead to incorrect memory accesses:
With DTS having too big value of input or output ports, the driver, when copying port parameters from local/stack arrays into 'pconfig' array in 'struct qcom_swrm_ctrl', will iterate over their sizes.
If DTS also has too many parameters for these ports (e.g. qcom,ports-sinterval-low), the driver will overflow buffers on the stack when reading these properties from DTS.
Add a sanity check so incorrect DTS will not cause kernel memory corruption.
Signed-off-by: Krzysztof Kozlowski krzysztof.kozlowski@linaro.org
Fixes: 02efb49aa805 ("soundwire: qcom: add support for SoundWire controller")
Can be... but is it really a bug of the kernel? Issue is visible with incorrect DTS and it's not the kernel's job to fix it. If DTS has incorrect values (e.g. IO addresses) system won't work anyway and that's the same type of bug.
I'm not sure to what extent the kernel should be responsible for checking DT sanity, but in case of a buffer overflow, I really think it definitely deserves a fixes tag.
Konrad
Best regards, Krzysztof