Setuid explanation

Operating Systems & Open Source Linux
1

I learn about Linux security, and as a part of it, I run following command on Manjaro / Gnome system:

sudo find / -perm /u+s

at the end of the output I’ve found

/opt/brave.com/brave-beta/chrome-sandbox

I assume that it’s a feature, but having web browser with Setuid seems for me to be not a good idea. Am I right?

Quite a lot of entries that were already deleted. Most of them in ‘/proc’ directory, but one in Firefox cache. Is it to worry about?
I have Gnome shell integration extension installed, but since reboot wasn’t using it.
How can an item in browser cache get setuid?
Why I can find it, but it is : “No such file or directory”?

find: ‘/home/qbecks/.cache/mozilla/firefox/67i8nc17.default-release/cache2/entries/6B4481D79B0F02FA4F89F9A3FEEDF973C67F3CA5’: No such file or directory
2

I believe the specifics about this is that user namespaces (a feature used to limit privileges of processes) requires root on some distros, since enabling them for users may be a security issue. At the very least firefox on my system doesn’t use it, but many electron apps appear to.

That line from find “No such file or directory” normally means that a file was deleted while find was running, and does not form part of the return result. Run “find … 2> /dev/null” to filter these out.

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