From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x224nOZ8KfC6/b9p79D+UYKwEKYwgnm51zXhr5a/kz/DOZK4lU5aXAeSa8kAX+XJkDjhnkRsu ARC-Seal: i=1; a=rsa-sha256; t=1516810795; cv=none; d=google.com; s=arc-20160816; b=wP++u8R0AO+x9O2hU20ljsF6ET5vf7+pbZ1wtciR2UVXCoXnZ0Y5Y5nhKd4ePv0ga6 ncU2KNIxX0lP/vULcGhlWUSP3CNL8/6ocLH/q0RrXiGSFQoeSp7iW998i1KpUb9LGkpd 1Z4WrW/ZL5xfERbVdkRI7+3pJD9fkSZbwuiXmHsPfAnYXqCGOdf54+ZaFnOGWY3tp+cU ox9MvLERF+vi18mkDXP/seBDp4EF1GwLxoiUIakXzuObMxRkOVg78F25NH8EemDKBhWF bexvFgw7zH+NcQ4+gX6ke74+daNanriKY4XehfFcgmHjudw6+OovIf+HZmO1LALsWc6F LFKg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=user-agent:in-reply-to:content-disposition:mime-version:references :message-id:subject:cc:to:from:date:dkim-signature :arc-authentication-results; bh=LYdTvo7qQGnHlC8bHynWlr78CAdlB8Dzr0IGZr9TLig=; b=ZKr2r4GGfqfrcdHS/mQdC2J9/W7/wi70NwElH84xXuwb/6f9Z73ltptvdDW1mrS5Ra veLVk7DpQ/nMyJdlw2nr13KrFzbMCNPokC4Rec2q5tpPVbrG0Btu1CQ1ODU0AyIvuC6w fum8bx3JOqZP64azhXGt6dzjtdWdzK9ITZZ+w/hROHI2B2Q0Dsvj16eFNABBOSEKZnDN ZjaWra2kcAny4uUD/Dqpf83faW0f+mwmFTOvzUWHSk26OkIj3GZE89O1egHF1jlnnT/U EHhLeA63PBioIt/dreSEdQrib86xhxgDMTQHI5qTANPzLcABqPFEi4UEQL3tIbiRZVe5 Vq2w== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@sirena.org.uk header.s=20170815-heliosphere header.b=PIZVNBES; spf=pass (google.com: domain of broonie@sirena.org.uk designates 2a01:7e01::f03c:91ff:fed4:a3b6 as permitted sender) smtp.mailfrom=broonie@sirena.org.uk Authentication-Results: mx.google.com; dkim=pass header.i=@sirena.org.uk header.s=20170815-heliosphere header.b=PIZVNBES; spf=pass (google.com: domain of broonie@sirena.org.uk designates 2a01:7e01::f03c:91ff:fed4:a3b6 as permitted sender) smtp.mailfrom=broonie@sirena.org.uk Date: Wed, 24 Jan 2018 16:19:41 +0000 From: Mark Brown To: Lars-Peter Clausen Cc: David Lechner , linux-kernel@vger.kernel.org, Greg Kroah-Hartman Subject: Re: [PATCH 1/2] regmap: fix NULL pointer dereference in regmap_name_read_file() Message-ID: <20180124161941.GI9366@sirena.org.uk> References: <1516748023-17235-1-git-send-email-david@lechnology.com> <1516748023-17235-2-git-send-email-david@lechnology.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="CD/aTaZybdUisKIc" Content-Disposition: inline In-Reply-To: X-Cookie: Love thy neighbor, tune thy piano. User-Agent: Mutt/1.9.2 (2017-12-15) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1590425592886901979?= X-GMAIL-MSGID: =?utf-8?q?1590491397040776948?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: --CD/aTaZybdUisKIc Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed, Jan 24, 2018 at 05:14:50PM +0100, Lars-Peter Clausen wrote: > On 01/23/2018 11:53 PM, David Lechner wrote: > > This fixes a possible NULL pointer dereference oops in > > regmap_name_read_file() when the regmap does not have a device > > associated with it. > > - ret = snprintf(buf, PAGE_SIZE, "%s\n", map->dev->driver->name); > > + if (map->dev && map->dev->driver) > > + name = map->dev->driver->name; > > + > > + ret = snprintf(buf, PAGE_SIZE, "%s\n", name); > Won't this print "(null)" now? Not sure if that is the best approach. Indeed. It is an improvement but not exactly helpful. --CD/aTaZybdUisKIc Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAlposh0ACgkQJNaLcl1U h9C7VwgAhbYbtRry78v8KUpZ4ZPu4LtrGiA939mqzFL27f99MPxWIL+H7rGtO4lD 4suTQhzQt0/U0GTywi5TsriazSZ1cHOXv6yOdUgehAuf3GqSEsrRsLvLuzEJdEar Xnoi79mfHZTynAElvvHA16NjlEGEJPhlXzFR+HtAo2ol95wmdIf1HM9le+jmXo3i HwKoEkaAS0dVIEbnn7K5ASfRYLOE5bmXOZDnnkaewSGv3YSQnH1zttvFxbhZK/ji H7zad6PcLvJluLjzadf9cKrMK1r3dJs+IQLngm9SdnJZS4Zv0hRbduuhn2bG1GbL 4ul6Lsb/TcWkRHt7Euwcgb9wghNZIg== =H9N7 -----END PGP SIGNATURE----- --CD/aTaZybdUisKIc--