From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jingoo Han Subject: Re: [PATCH] i2c: busses: i2c-pxa.c: Fix for possible null pointer dereference Date: Mon, 02 Jun 2014 10:55:43 +0900 Message-ID: <004801cf7e05$c3354c20$499fe460$%han@samsung.com> References: <1400346848-25098-1-git-send-email-rickard_strandqvist@spectrumdigital.se> <20140601202647.GD3853@katana> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: In-reply-to: <20140601202647.GD3853@katana> Content-language: ko Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: 'Rickard Strandqvist' , 'Wolfram Sang' Cc: 'Grant Likely' , 'Rob Herring' , 'Leilei Shang' , 'Daniel Drake' , linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, 'Jingoo Han' List-Id: linux-i2c@vger.kernel.org On Monday, June 02, 2014 5:27 AM, Wolfram Sang wrote: > On Sat, May 17, 2014 at 07:14:08PM +0200, Rickard Strandqvist wrote: > > There is otherwise a risk of a possible null pointer dereference. > > > > Was largely found by using a static code analysis program called cppcheck. > > It is useful to put the output of the analyzer here. > > > > > Signed-off-by: Rickard Strandqvist > > --- > > drivers/i2c/busses/i2c-pxa.c | 4 +++- > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c > > index bbe6dfb..dbe5ebe 100644 > > --- a/drivers/i2c/busses/i2c-pxa.c > > +++ b/drivers/i2c/busses/i2c-pxa.c > > @@ -1269,7 +1269,9 @@ eremap: > > eclk: > > kfree(i2c); > > emalloc: > > - release_mem_region(res->start, resource_size(res)); > > + if(res) { > > + release_mem_region(res->start, resource_size(res)); > > + } > > The proper fix is to move the release to the proper place, before kfree. > Even better would probably be a devm_* conversion. +1 I agree with Wolfram Sang's opinion. Please call release_mem_region() prior to kfree(). One more thing, don't use braces when a single statement is used. Please refer to 'Chapter 3: Placing Braces and Spaces' of 'Documentation/CodingStyle'. Best regards, Jingoo Han -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html