Re: [PATCH] for-each-ref: fix off by one read.

From: Christian Couder <chriscool@tuxfamily.org>
Date: Nov 13, 2007, 05:15 UTC
Message-ID: <200711130615.54196.chriscool@tuxfamily.org>
In-Reply-To: <7vfxzb1032.fsf@gitster.siamese.dyndns.org>

Le mardi 13 novembre 2007, Junio C Hamano a écrit :

Show 16 quoted lines

> Christian Couder <chriscool@tuxfamily.org> writes:
> > diff --git a/builtin-for-each-ref.c b/builtin-for-each-ref.c
> > index 598d4e1..89ea37c 100644
> > --- a/builtin-for-each-ref.c
> > +++ b/builtin-for-each-ref.c
> > @@ -306,7 +306,7 @@ static const char *find_wholine(const char *who,
> > int wholen, const char *buf, un if (!eol)
> >  			return "";
> >  		eol++;
> > -		if (eol[1] == '\n')
> > +		if (*eol == '\n')
> >  			return ""; /* end of header */
> >  		buf = eol;
> >  	}
>
> Good eyes.

Well, Valgrind found it when I did:

$ valgrind git for-each-ref --format='%(refname)' "refs/tags/*"

> This would have broken if

Show 6 quoted lines

>  (1) we had a header field that consists of a single character
>      and then LF.  We would have mistaken such a line as the end
>      of header; or
>
>  (2) we had a commit or a tag that consists solely of header and
>      no body.  We would have read past the terminating NUL.

I suspect that the end of the header was not properly detected, so that it may have read one byte past a body ending with LF and the terminating NUL.

Christian.