Al Viro <[EMAIL PROTECTED]> wrote: > 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. Since nobody knows about this "security boundary" and everybody knows about the annoying "can't link across bind-mountpoints bug", what about introducing a mount option to allow link()ing? -- 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/
