netdev - Re: [iproute PATCH v3 2/5] nstat: Fix for potential NULL pointer dereference

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20170821171945.3d1f5a71@xeon-e3>
Date:   Mon, 21 Aug 2017 17:19:45 -0700
From:   Stephen Hemminger <stephen@...workplumber.org>
To:     Phil Sutter <phil@....cc>
Cc:     netdev@...r.kernel.org
Subject: Re: [iproute PATCH v3 2/5] nstat: Fix for potential NULL pointer
 dereference

On Mon, 21 Aug 2017 12:03:05 +0200
Phil Sutter <phil@....cc> wrote:

> If the string at 'p' contains neither space not newline, 'p' will become
> NULL. Make sure this isn't the case before dereferencing it.
> 
> Signed-off-by: Phil Sutter <phil@....cc>
> ---
> Changes since v2:
> - Call abort() if 'p' becomes NULL.
> ---
>  misc/nstat.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/misc/nstat.c b/misc/nstat.c
> index a4dd405d43a93..56e9367e99736 100644
> --- a/misc/nstat.c
> +++ b/misc/nstat.c
> @@ -217,6 +217,8 @@ static void load_ugly_table(FILE *fp)
>  			n->next = db;
>  			db = n;
>  			p = next;
> +			if (!p)
> +				abort();
>  		}
>  		n = db;
>  		if (fgets(buf, sizeof(buf), fp) == NULL)

This doesn't do anything better than just dereferencing NULL.
In either case program crashes with no useful information to user.
Not applying this.