Re: SYSFS "errors"

[Greg KH <gregkh@linuxfoundation.org>]

On Mon, Feb 18, 2013 at 05:33:16PM +0200, Felipe Balbi wrote:
> Hi folks,
> 
> there are today a number of SYSFS files with read permission set but
> can't really be read (tried with normal user and root). To make things
> simpler, I wrote a simple ruby script (see below) to check if the file
> is world writeable or if it has Read permission but throws an exception
> when read (note that I ignore files which return empty buffers since
> ruby cries about it).
> 
> Here are some results from my desktop PC:
> 
> $ ruby sysfs_errors.rb |wc -l
> 968
> 
> # ruby sysfs_errors.rb | wc -l
> 1602
> 
> 8<---------------------------- cut here --------------------------------
> 
> Dir.glob("/sys/**/*").each do |file|
> 	next if File.directory?(file)
> 
> 	if File.world_writable?(file)
> 		puts "#{file} is world-writable"
> 	end
> 
> 	if File.readable?(file)
> 		begin
> 			File.open(file) { |f|
> 				result = f.readline
> 			}
> 		rescue EOFError
> 			nil
> 		rescue => e
> 			puts e.message
> 		end
> 	end
> end
> 
> I wonder if that should be sorted out or should we leave it as is ?

They should be sorted out.

> If it helps in any way, I have printed below only the filenames
> (without path) so I could pipe it through uniq:
> 
> act_mask
> audit
> autosuspend_delay_ms
> bind

This one the driver core creates, I'll fix that up.

The rest need paths to determine who to blame :)

thanks,

greg k-h