Messages in this thread | | | Date | Wed, 15 Mar 2023 13:55:47 +0000 | Subject | Re: [PATCH 2/2] soundwire: qcom: gracefully handle too many ports in DT | From | Srinivas Kandagatla <> |
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On 22/02/2023 14:44, 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: > 1. 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. > > 2. 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> > ---
Thanks Krzysztof, it make sense.
Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
--srini > drivers/soundwire/qcom.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c > index 79bebcecde6d..c296e0bf897b 100644 > --- a/drivers/soundwire/qcom.c > +++ b/drivers/soundwire/qcom.c > @@ -1218,6 +1218,9 @@ static int qcom_swrm_get_port_config(struct qcom_swrm_ctrl *ctrl) > ctrl->num_dout_ports = val; > > nports = ctrl->num_dout_ports + ctrl->num_din_ports; > + if (nports > QCOM_SDW_MAX_PORTS) > + return -EINVAL; > + > /* Valid port numbers are from 1-14, so mask out port 0 explicitly */ > set_bit(0, &ctrl->dout_port_mask); > set_bit(0, &ctrl->din_port_mask);
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