Re: [PATCH] missing checks in exec_permission_light()

[Alexander Viro]

On Fri, 3 May 2002, Pavel Machek wrote:

> Hi!
> 
> > +	if (S_ISDIR(inode->i_mode) && capable(CAP_DAC_READ_SEARCH))
> > +		return 0;
> 
> Is this right? This means that root can do cat /, no? That does not
> seem like expected behaviour.

1) it's permission(..., MAY_EXEC)
2) in any case, root _can_ open "/" with O_RDONLY.  Always could.  That's
what you do for ls /, after all - open(2) followed by getdents(2).  Now,
read(2) will fail (check what ->read() for directories is set to), but
that has nothing to permission checks.