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Message-ID: <78873437-3b35-0711-a1dc-219b9f316fac@quicinc.com>
Date:   Tue, 31 May 2022 08:25:26 -0700
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From:   Prasad Sodagudi <quic_psodagud@quicinc.com>
Subject: [Query] Looking for comments on CONFIG_SPI_SPIDEV and
 CONFIG_I2C_CHARDEV interfaces security
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Hi All,

I am working on an IoT solution and would like to understand security 
impact of these two CONFIG_SPI_SPIDEV and CONFIG_I2C_CHARDEV interfaces 
of Linux. If a driver is developed from userspace for  /dev/spiX.Y or 
/dev/i2c interfaces,  are there any security concerns ?

Userspace driver is to control external SPI slave on board. I heard that 
these interfaces allows access to any of these type of devices on board. 
  How to avoid accessing any of these type of unwanted device access 
from userspace ?  Can Selinux or any mechanism control access to other 
these type of devices from user-space ?

Please share your comments/findings on these two interfaces related to 
security. If community had posted any security related discussions with 
these interfaces, please share details to improve understanding.

-Thanks, Prasad