From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from smtp.mei.co.jp ([133.183.100.20]) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1YGmdj-0007wf-6F for barebox@lists.infradead.org; Thu, 29 Jan 2015 10:48:00 +0000 Date: Thu, 29 Jan 2015 19:47:31 +0900 From: Masahiro Yamada In-Reply-To: <20150129093212.GJ18908@pengutronix.de> References: <20150129182138.3DA6.AA925319@jp.panasonic.com> <20150129093212.GJ18908@pengutronix.de> Message-Id: <20150129194731.3DAE.AA925319@jp.panasonic.com> MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH v2] param: add error check to __dev_add_param() To: Sascha Hauer Cc: barebox@lists.infradead.org Hi Sascha, On Thu, 29 Jan 2015 10:32:12 +0100 Sascha Hauer wrote: > On Thu, Jan 29, 2015 at 06:21:39PM +0900, Masahiro Yamada wrote: > > Hi Sascha, > > > > On Thu, 29 Jan 2015 10:06:22 +0100 > > Sascha Hauer wrote: > > > > > On Thu, Jan 29, 2015 at 11:46:53AM +0900, Masahiro Yamada wrote: > > > > If the argument, name is given with NULL, it would be probably > > > > unexpected behavior. It should fail rather than register the > > > > NULL-named parameter. > > > > > > > > If strdup() fails with out-of-memory, it should also fail > > > > with -ENOMEM. > > > > > > > > Signed-off-by: Masahiro Yamada > > > > --- > > > > > > > > Changes in v2: > > > > - Fix the condition of returning -ENOMEM > > > > > > > > lib/parameter.c | 8 +++++++- > > > > 1 file changed, 7 insertions(+), 1 deletion(-) > > > > > > > > diff --git a/lib/parameter.c b/lib/parameter.c > > > > index 71262c4..02a89bb 100644 > > > > --- a/lib/parameter.c > > > > +++ b/lib/parameter.c > > > > @@ -130,6 +130,13 @@ static int __dev_add_param(struct param_d *param, struct device_d *dev, const ch > > > > if (get_param_by_name(dev, name)) > > > > return -EEXIST; > > > > > > > > + if (!name) > > > > + return -EINVAL; > > > > > > Name is used already two lines above so barebox will already be crashed > > > before this triggers. > > > > > > Besides, I normally don't like these checks. dereferencing NULL pointers > > > means you get a backtrace showing you what went wrong. Returning an error > > > means adding code which in this case makes dev_add_param just fail > > > silently because the return value often is not checked. > > > > > > > OK, then how about dropping this -EINVAL check? > > Yes, please. I did that in v3. > > > > I think the -ENOMEM check below is still useful. > > ( strdup() returns NULL also when NULL is passed, > > but in that case this line cannot be reached. > > The problem is that is not apparent at a glance..) > > Note we also have xstrdup which crashes barebox on out of memory. This > is usually the right thing to do when it's known that the allocation is > small. > I stopped and I have been thinking about it. I hesitate a bit to replace it with xstrdup(). I feel like being lazy. So, I did not do this in v3. Best Regards Masahiro Yamada _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox