RE: [PATCH 2/4] fs: define a firmware security filesystem named fwsecurityfs

From: James Bottomley

Sent: 21 November 2022 14:03

...

quoted

Then how does the networking code handle the namespace stuff in
sysfs?
That seems to work today, or am I missing something?

have you actually tried?

jejb@lingrow:~> sudo unshare --net bash
lingrow:/home/jejb # ls /sys/class/net/
lo  tun0  tun10  wlan0
lingrow:/home/jejb # ip link show
1: lo: <LOOPBACK> mtu 65536 qdisc noop state DOWN mode DEFAULT group
default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00

So, as you see, I've entered a network namespace and ip link shows me
the only interface I can see in that namespace (a down loopback) but
sysfs shows me every interface on the system outside the namespace.

You have to remount /sys to get the restricted copy.
eg by running 'ip netns exec namespace command'.

	David

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