O_EXCL over NFS: Don't!!! (Repost in HTML)
Posted Sep 27, 2007 22:39 UTC (Thu) by cras
In reply to: O_EXCL over NFS: Don't!!! (Repost in HTML)
Parent article: Exploiting symlinks and tmpfiles
I've read hearsay that it's supposed to work under NFSv3 ... but I haven't seen a convincing, credible
statement to that effect.
My NFS tester shows that it at least appears to work with Linux, Solaris and FreeBSD:
http://www.dovecot.org/list/dovecot/2007-July/024102.html. Looking at Linux 2.6 sources it
doesn't look like it tries to implement a racy O_EXCL check in client side (fs/nfs/nfs3proc.c
nfs3_proc_create()), so the test's results
should be correct. I don't know if other OSes do that. I guess it would be nice to have a better
O_EXCL tester which tries to catch race conditions.
to post comments)