From owner-freebsd-current@FreeBSD.ORG  Wed Dec 15 10:56:58 2004
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To: Ruslan Ermilov <ru@FreeBSD.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Wed, 15 Dec 2004 12:53:27 +0200."
             <20041215105326.GO25967@ip.net.ua> 
Date: Wed, 15 Dec 2004 11:56:57 +0100
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cc: current@FreeBSD.org
Subject: Re: Background fsck is broken 
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In message <20041215105326.GO25967@ip.net.ua>, Ruslan Ermilov writes:

>Are you saying it's not possible to downgrade the open to
>(r=1, w=0, e=0) when a file system is downgraded from R/W to R/O?

Yes: that would make a read-only mounted filesystem vulnerable to
overwriting through the /dev entry and we don't want that.

The problem is that we do not in the kernel know if we are in single
user mode or not.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.