Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!uunet!mcsun!ukc!stl!agm
From: agm@stl.stc.co.uk (Andrew G. Minter)
Newsgroups: comp.os.minix
Subject: Re: FS bug?
Message-ID: <3873@stl.stc.co.uk>
Date: 21 Dec 90 11:38:05 GMT
References: <1990Dec21.003030.4379@cocktrice.uucp>
Sender: news@stl.stc.co.uk
Reply-To: "Andrew G. Minter" <agm@stl.stc.co.uk>
Organization: STC Technology Limited, London Road, Harlow, Essex, UK
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>login cannot exec /bin/sh when it has been changed to 511;

I've seen this problem before, and I believe the it is in the MM.  If my
memory serves me correctly the MM, when executing an exec, somehow changes
it's effective user id to that of the user before calling the FS.  If it
didn't do this, the FS would think the request was coming from a process
running as root and would treat permissions of files and directories
accordingly.  Since the MM has to read the file (using read calls) to load
it in, it needs to have read permission.

The problem is by no means insoluble, but it will take more than a simple
patch to fix.

Perhaps this will be fixed in AST's 1.6, drool, drool.

Andrew