Re: [RFC] fs, proc: Introduce the /proc/<pid>/map_files/ directory v2

[Pavel Emelyanov <xemul@parallels.com>]

On 09/13/2011 06:14 PM, Pavel Machek wrote:
> Hi!
> 
>> This one behaves similarly to the /proc/<pid>/fd/ one - it contains symlinks
>> one for each mapping with file, the name of a symlink is vma->vm_start, the
>> target is the file. Opening a symlink results in a file that point exactly
>> to the same inode as them vma's one.
> 
> Is it good idea security-wise? It looks like symlink but does not
> behave like one. (And yes, I know we already have similar problems in
> /proc..)

What exactly doesn't behave like symlink, can you elaborate, please?

> ptrace-may-trace is not good enough protection; I can do  this on my
> own thread to get around read-only protection on fd. (File can be
> protected from me by directory permissions.)

I think this issue worth separate discussion and if it turns out there is
a problem with that we can fix it together with /proc/pid/fd and other stuff.

Thanks,
Pavel