From mboxrd@z Thu Jan  1 00:00:00 1970
From: Johannes Sixt <j.sixt@viscovery.net>
Subject: Re: [PATCH] quickfetch(): Prevent overflow of the rev-list command
 line
Date: Wed, 08 Jul 2009 17:12:21 +0200
Message-ID: <4A54B755.4090100@viscovery.net>
References: <alpine.DEB.2.00.0906181310400.23400@ds9.cixit.se> <alpine.DEB.2.00.0906221342310.26061@ds9.cixit.se> <200907081558.51767.johan@herland.net>
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Cc: Junio C Hamano <gitster@pobox.com>, git@vger.kernel.org,
	Peter Krefting <peter@softwolves.pp.se>,
	"Shawn O. Pearce" <spearce@spearce.org>
To: Johan Herland <johan@herland.net>
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Johan Herland schrieb:
> +	/* If rev-list --stdin encounters an unknown commit, it terminates,
> +	 * which will cause SIGPIPE in the write loop below. */

Under the conditions you describe here...

> +	signal(SIGPIPE, SIG_IGN);

... and SIGPIPE being ignored...

> +
> +	err = start_command(&revlist);
> +	if (err) {
> +		error("could not run rev-list");
> +		return err;
> +	}
>  
> -	for (i = 0; argv[i]; i++)
> -		free(argv[i]);
> -	free(argv);
> -	return err;
> +	for (ref = ref_map; ref; ref = ref->next) {
> +		if (write_in_full(revlist.in, sha1_to_hex(ref->old_sha1), 40) < 0 ||
> +		    write_in_full(revlist.in, "\n", 1) < 0) {
> +			error("failed write to rev-list");
> +			err = errno;

... don't you get this error message with errno set to EPIPE? Previously,
there was no error message.

-- Hannes