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Date: Fri, 16 Dec 2005 23:15:22 +0000
From: "Wojciech A. Koszek" <dunstan@freebsd.czest.pl>
To: freebsd-current@freebsd.org
Message-ID: <20051216231521.GA59072@FreeBSD.czest.pl>
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Subject: [PATCH] sbuf_copyin() can return number of bytes copied from
	user-space
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Hello,

Function sbuf_copyin() at current stage makes no use of "done" argument,
used internally. "done", which is a result of copying string from
user-space address with copyinstr(), contains number of bytes copied. We
can easily extend current implementation:

http://freebsd.czest.pl/dunstan/FreeBSD/sbuf_copyin.0.patch

I'd like to receive comments from people making use of sbuf_copyin() in
their sources. This change will probably make it necessary to compare
return value with -1 in order to detect failure. At current stage,
existing FreeBSD code uses sbuf_copyin in two files, both ignoring
return value, so this shouldn't break anything.

If noone will object, above change will probably be commited. 

Comments are welcome!
-- 
* Wojciech A. Koszek && dunstan@FreeBSD.czest.pl