Re: [PATCH] one of $BIGNUM devfs races

Alexander Viro
2001-08-08T21:47:34Z

On 8 Aug 2001, H. Peter Anvin wrote:

> Followup to: <Pine.GSO.4.21.0108071510390.18565-100000@weyl.math.psu.edu>
> By author: Alexander Viro <viro@math.psu.edu>
> In newsgroup: linux.dev.kernel
> >
> > It is not reliable. E.g. on NFS inumbers are not unique - 32 bits is
> > not enough.
> >
>
> Unfortunately there is a whole bunch of other things too that rely on
> it, and *HAVE* to rely on it -- (st_dev, st_ino) are defined to
> specify the identity of a file, and if the current types aren't large
> enough we *HAVE* to go to new types. THERE IS NO OTHER WAY TO TEST
> FOR FILE IDENTITY IN UNIX, and being able to perform such a test is
> vital for many things, including security and hard link detection

Indeed, but it still doesn't help libc5 getcwd(3), which uses 32 bit
values.

> (think tar, cpio, cp -a.)

I'd rather not. Too bloody depressive... (If you want details - let's
take it off-list).