Re: [Patch 1/2] selinux: ajust rules for ATTR_FORCE

[Stephen Smalley <sds@tycho.nsa.gov>]

On Tue, 2009-08-18 at 16:39 +0900, OGAWA Hirofumi wrote:
> [Sorry if this killed thread. My ISP seems to be stopping email server
> now. I've read this email from web archive.]
> 
> >> @@ -2711,12 +2711,17 @@ static int selinux_inode_permission(stru
> >>  static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
> >>  {
> >>  	const struct cred *cred = current_cred();
> >> +	unsigned int ia_valid = iattr->ia_valid;
> >>  
> >> -	if (iattr->ia_valid & ATTR_FORCE)
> >> -		return 0;
> >> +	/* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
> >> +	if (ia_valid & ATTR_FORCE) {
> >> +		ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE);
> >> +		if (!ia_valid)
> >> +			return 0;
> >>   
> > 
> > So if I read this correctly, (ATTR_FORCE| ATTR_KILL_SUID|ATTR_MODE) will 
> > not return here, since 'ia_valid' will be ATTR_FORCE finally.
> > 
> > I think you forgot to clear ATTR_FORCE here...
> 
> Whoops, good catch. Fortunately, it doesn't seem to have actual problem,
> but it's bug obviously, and sorry for that. Fixed patch was attached.

You can add my:
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>

-- 
Stephen Smalley
National Security Agency