On Fri, Aug 16, 2024 at 12:12 PM Barry barry@barrys-emacs.org wrote:
On 16 Aug 2024, at 08:54, Frederic Muller fred@cm17.com wrote:
Serial port also requires sudo ( /dev/ttyACM0 ) for betaflight to be able to access it
Look into adding a udev rule to set the permissions you need on the serial device. Then you can avoid using sudo.
Or add the user that needs this access to the "dialout" group (and log out and back in so the group gets added to the user). By default that group is put on serial ports and that group has full rw.
sudo became required for dmesg as unpriv’ed access to the dmesg logs is a security risk that can being exploited by malware.
Barry
sysctl -w kernel.dmesg_restrict=0 and setting that parameter in a /etc/sysctl.d so it gets done at boot returns the original behavior.
Though as noted it is possible to gain useful information that malware may be able to use to break out of being an unpriv'ed user to become prived.