From: Florian Obser <florian@openbsd.org>
Subject: Re: traceroute: fix segfault when some arguments are repeated
To: tech@openbsd.org
Date: Mon, 16 Feb 2026 13:38:31 +0100

Nice one.

OK florian or I can commit it if someone wants to OK it.

On 2026-02-14 08:17 +02, Petre Rodan <petre.rodan@subdimension.ro> wrote:
> Hi,
>
> Make sure that internal counters do not go out of bounds
> if the '-n' or '-A' options are specified more than once.
>
> best regards,
> peter
> --
>
> Index: traceroute.c
> ===================================================================
> RCS file: /cvs/src/usr.sbin/traceroute/traceroute.c,v
> diff -u -p -r1.170 traceroute.c
> --- traceroute.c	21 Aug 2024 15:00:25 -0000	1.170
> +++ traceroute.c	14 Feb 2026 05:54:28 -0000
> @@ -429,8 +429,10 @@ main(int argc, char *argv[])
>  	    "ADdf:g:Ilm:nP:p:q:Ss:t:V:vw:x")) != -1)
>  		switch (ch) {
>  		case 'A':
> -			conf->Aflag = 1;
> -			conf->expected_responses++;
> +			if (!conf->Aflag) {
> +				conf->Aflag = 1;
> +				conf->expected_responses++;
> +			}
>  			break;
>  		case 'd':
>  			conf->dflag = 1;
> @@ -479,8 +481,10 @@ main(int argc, char *argv[])
>  				    conf->first_ttl, MAXTTL);
>  			break;
>  		case 'n':
> -			conf->nflag = 1;
> -			conf->expected_responses--;
> +			if (!conf->nflag) {
> +				conf->nflag = 1;
> +				conf->expected_responses--;
> +			}
>  			break;
>  		case 'p':
>  			conf->port = strtonum(optarg, 1, 65535, &errstr);
>

-- 
In my defence, I have been left unsupervised.