Mime-Version: 1.0
Subject: RE: [PATCH] PM / devfreq: Fix potential NULL pointer dereference in
 governor_store
Reply-To: myungjoo.ham@samsung.com
From: MyungJoo Ham <myungjoo.ham@samsung.com>
To: Kyungmin Park <kyungmin.park@samsung.com>,
        Chanwoo Choi <cw00.choi@samsung.com>
CC: "linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "Gustavo A. R. Silva" <garsilva@embeddedor.com>
In-Reply-To: <20171206202015.GA15636@embeddedor.com>
Message-ID: <20171207024144epcms1p4d7e1a981c7c307190a85e8c35174d983@epcms1p4>
Date: Thu, 07 Dec 2017 02:41:44 +0000
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References: <20171206202015.GA15636@embeddedor.com>
        <CGME20171206202020epcas3p4fe9a9fb5346f2d413199ed71d1d0f19f@epcms1p4>
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> df->governor is being dereferenced before it is null checked,
> hence there is a potential null pointer dereference.
> 
> Notice that df->governor is being null checked at line 1004:
> if (df->governor) {, which implies it might be null.
> 
> Fix this by null checking df->governor before dereferencing it.
> 
> Addresses-Coverity-ID: 1401988 ("Dereference before null check")
> Fixes: bcf23c79c4e4 ("PM / devfreq: Fix available_governor sysfs")
> Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>

Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>


Cheers,
MyungJoo

> ---
>  drivers/devfreq/devfreq.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index 78fb496..14fe76b 100644