Date: Mon, 18 Sep 2000 16:03:14 -0400 (EDT) From: Adrian Filipi-Martin <adrian@ubergeeks.com> To: Bruce Evans <bde@zeta.org.au> Cc: Ben Smithurst <ben@FreeBSD.ORG>, Poul-Henning Kamp <phk@critter.freebsd.dk>, Peter Pentchev <roam@orbitel.bg>, Julian Elischer <julian@elischer.org>, Chris Costello <chris@calldei.com>, hackers@FreeBSD.ORG, current@FreeBSD.ORG Subject: Re: Fdescfs updates--coming to a devfs near you! Message-ID: <Pine.BSF.4.10.10009181559480.26242-100000@lorax.ubergeeks.com> In-Reply-To: <Pine.BSF.4.21.0009190028380.16912-100000@besplex.bde.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Tue, 19 Sep 2000, Bruce Evans wrote: > On Sun, 17 Sep 2000, Adrian Filipi-Martin wrote: > > > I recently ran into revelant problem with /dev/stdout, while > > working on some software under linux that expected /dev/stdout as an > > argument instead of using stdout. > > > > Using the device file breaks, if the process is suid to a non-root > > user. This is because it cannot open /dev/stdout, which is owned by your > > UID and not the EUID of the process to which the device was passed. My > > solution was to add the "-" hack and use the existing open descriptor. > > Um, open on fdesc devices doesn't check either uid. It just checks > the access mode. > > Perhaps the software expected /dev/stdout to for read-write like a > tty would be. Then opening /dev/stdout would fail for normal shell > output redirection which only opens for writing. No, it wasn't a RW/W issue. I dug a little deeper. It looks like the BSD implmentation of /dev/stdout is smarter than the linux version. Linux's is a symlink into /proc and the device ownership is determined by the UID of the invoking user. I guess I wouldn't have have had a problem under BSD. no suprise here. Adrian -- [ adrian@ubergeeks.com -- Ubergeeks Consulting -- http://www.ubergeeks.com/ ] To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.BSF.4.10.10009181559480.26242-100000>