Re: [PATCH 1/5] WIP: Add syscall unlinkat_s (currently x86* only)

[Davidlohr Bueso <dave@stgolabs.net>]

On Tue, 2015-02-03 at 07:58 +0100, Alexander Holler wrote:
> Am 03.02.2015 um 07:05 schrieb Al Viro:
> > On Mon, Feb 02, 2015 at 06:05:09PM +0100, Alexander Holler wrote:
> >> +	if (inode) {
> >> +		// TODO:
> >> +		// if (inode is file and 's' flag is set)
> >> +		// 	secure = true;
> >> +		if (!secure)
> >> +			iput(inode);	/* truncate the inode here */
> >> +		else {
> >> +			struct super_block *sb = inode->i_sb;
> >> +			if (sb->s_op->set_secure_delete)
> >> +				sb->s_op->set_secure_delete(sb, true);
> >> +			// TODO: We should fail if secure isn't supported,
> >> +			// look up how that's possible here.
> >> +			iput(inode);	/* truncate the inode here */
> >> +			// TODO: check if sb is still valid after the inode is gone
> >> +			sync_filesystem(sb);
> >> +			if (sb->s_op->set_secure_delete)
> >> +				sb->s_op->set_secure_delete(sb, false);
> >> +		}
> > 
> > Charming.  Now, what exactly happens if two such syscalls overlap in time?
> 
> What do you think will happen? I assume you haven't looked at how I've
> implemented set_secure_delete(). CHarming.

Chill, why don't you.