On Tue, Dec 18, 2007 at 11:00:16PM +0000, Al Viro wrote: > On Tue, Dec 18, 2007 at 05:46:21PM -0500, Mark Lord wrote: > > Why does link(2) not support hard-linking across bind mount points > > of the same underlying filesystem ? > > Because it gives you a security boundary around a subtree.
PS: that had been discussed quite a few times, but to avoid searches: consider e.g. mount --bind /tmp /tmp; now you've got a situation when users can't create links to elsewhere no root fs, even though they have /tmp writable to them. Similar technics works for other isolation needs - basically, you can confine rename/link to given subtree. IOW, it's a deliberate feature. Note that you can bind a bunch of trees into chroot and get predictable restrictions regardless of how the stuff might get rearranged a year later in the main tree, etc. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
