linux-kernel - Re: [PATCH] nfsd: Make creates return EEXIST correctly instead of EPERM

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Sat, 9 Jul 2016 03:52:30 +0100
From:	Al Viro <viro@...IV.linux.org.uk>
To:	Oleg Drokin <green@...uxhacker.ru>
Cc:	Jeff Layton <jlayton@...chiereds.net>,
	"J. Bruce Fields" <bfields@...ldses.org>,
	linux-nfs@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] nfsd: Make creates return EEXIST correctly instead of
 EPERM

On Fri, Jul 08, 2016 at 11:59:50AM -0400, Oleg Drokin wrote:

> "If path names a symbolic link, mkdir() shall fail and set errno to [EEXIST]."
> 
> This sounds pretty straightforward to me, no?
> Since it does not matter that we do not have write permissions here, because
> the name already exists.

When more than one condition applies, we have every right to return any of
them.  POSIX does *NOT* specify the order of checks.  Never had.