[PATCH] misc: ti-st: st_kim.c: Cleaning up missing null-terminate after strncpy call

[PATCH] misc: ti-st: st_kim.c: Cleaning up missing null-terminate after strncpy call

[Rickard Strandqvist]

Added a guaranteed null-terminate after call to strncpy.

Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
---
 drivers/misc/ti-st/st_kim.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/misc/ti-st/st_kim.c b/drivers/misc/ti-st/st_kim.c
index 9d3dbb2..bce4468 100644
--- a/drivers/misc/ti-st/st_kim.c
+++ b/drivers/misc/ti-st/st_kim.c
@@ -593,6 +593,7 @@ static ssize_t store_dev_name(struct device *dev,
 	struct kim_data_s *kim_data = dev_get_drvdata(dev);
 	pr_debug("storing dev name >%s<", buf);
 	strncpy(kim_data->dev_name, buf, count);
+	kim_data->dev_name[count - 1] = '\n';
 	pr_debug("stored dev name >%s<", kim_data->dev_name);
 	return count;
 }
-- 
1.7.10.4

Re: [PATCH] misc: ti-st: st_kim.c: Cleaning up missing null-terminate after strncpy call

[Mark D Rustad]

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On Aug 9, 2014, at 4:45 PM, Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se> wrote:

> Added a guaranteed null-terminate after call to strncpy.
> 
> Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
> ---
> drivers/misc/ti-st/st_kim.c |    1 +
> 1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/misc/ti-st/st_kim.c b/drivers/misc/ti-st/st_kim.c
> index 9d3dbb2..bce4468 100644
> --- a/drivers/misc/ti-st/st_kim.c
> +++ b/drivers/misc/ti-st/st_kim.c
> @@ -593,6 +593,7 @@ static ssize_t store_dev_name(struct device *dev,
> 	struct kim_data_s *kim_data = dev_get_drvdata(dev);
> 	pr_debug("storing dev name >%s<", buf);
> 	strncpy(kim_data->dev_name, buf, count);
> +	kim_data->dev_name[count - 1] = '\n';

Of course this does not add termination, but adds a newline at the end of the buffer? Huh?

> 	pr_debug("stored dev name >%s<", kim_data->dev_name);
> 	return count;
> }

-- 
Mark Rustad, MRustad@gmail.com


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Re: [PATCH] misc: ti-st: st_kim.c: Cleaning up missing null-terminate after strncpy call

[Wolfram Sang]

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> > 	strncpy(kim_data->dev_name, buf, count);
> > +	kim_data->dev_name[count - 1] = '\n';
> 
> Of course this does not add termination, but adds a newline at the end of the buffer? Huh?

strlcpy?


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Re: [PATCH] misc: ti-st: st_kim.c: Cleaning up missing null-terminate after strncpy call

[Rickard Strandqvist]

2014-08-11 11:14 GMT+02:00 Wolfram Sang <wsa@the-dreams.de>:
>
>> >     strncpy(kim_data->dev_name, buf, count);
>> > +   kim_data->dev_name[count - 1] = '\n';
>>
>> Of course this does not add termination, but adds a newline at the end of the buffer? Huh?
>
> strlcpy?
>

Hi Wolfram

Sure, strlcpy is preferable in many ways if we only can guarantee that
it is safe.
I have seldom been so much criticism when I start switching to
strlcpy, although much of it was justified :)
Even Linus was getting into the debate.  See more:

https://plus.google.com/111049168280159033135/posts/1amLbuhWbh5


I do this only when I'm sure it will not cause any other problems.
But if you or anyone else can guarantee that in this case, so I'd make
a new patch.


Kind regards
Rickard Strandqvist