Re: [PATCH] one of $BIGNUM devfs races

[Richard Gooch]

Alexander Viro writes:
> 
> 
> On Mon, 6 Aug 2001, Richard Gooch wrote:
> 
> > Again, historical reasons. When I wrote devfs, the pipe data trampled
> > the inode->u.generic_ip pointer. So that's no good. I see that the
> > pipe data has been moved away. Good. Hm. But there's still the
> > inode->u.socket_i structure. I'd need to check where that gets
> > trampled.
> 
> It isn't. socket_i is used only in inodes allocated by sock_alloc().
> It is not used in the inodes that live on any fs other than sockfs.

OK. Although, where is sockfs?

> For local-domain socket you get _two_ kinds of inodes, both with
> S_IFSOCK in ->i_mode: one on the filesystem (acting like an meeting
> place) and another - bearing the actual socket and used for all IO.
> 
> In other words, the only kind you can get from mknod(2) never uses
> ->i_socket. It's used only by bind() and connect() - and only as
> a place in namespace. The only thing we ever look at is ownership
> and permissions - they determine who can bind()/connect() here.
> 
> So ->u.generic_ip is safe.

Great! That table is toast! All I need is a spinlock-protected
incrementing counter :-)

				Regards,

					Richard....
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