Re: [patch] iio:imu: adis16480: show_firmware() buffer too small

[Jonathan Cameron <jic23@kernel.org>]

On 11/27/2012 06:41 PM, Lars-Peter Clausen wrote:
> On 11/27/2012 08:31 AM, Dan Carpenter wrote:
>> Smatch complains that snprintf() returns the number of characters,
>> not counting the NUL terminator, which *would* have been printed if
>> there were enough space.  In other words the return value could be more
>> than sizeof(buf).
>>
>> In this case, we are printing something like "ff.ff\n" which is at most
>> 6 characters and a NUL so that's not an issue.  I changed snprintf() to
>> scnprintf() to silence the warning.
>>
>> But since the buffer doesn't include space for the NUL terminator, we
>> need to make it bigger or the "\n" will be truncated off.
>>
> 
> 
> Thanks,
> 
> Acked-By: Lars-Peter Clausen <lars@metafoo.de>
> 
Added to togreg branch of

git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git

>> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
>>
>> diff --git a/drivers/iio/imu/adis16480.c b/drivers/iio/imu/adis16480.c
>> index a080b35..150d7fa 100644
>> --- a/drivers/iio/imu/adis16480.c
>> +++ b/drivers/iio/imu/adis16480.c
>> @@ -125,7 +125,7 @@ static ssize_t adis16480_show_firmware_revision(struct file *file,
>>  		char __user *userbuf, size_t count, loff_t *ppos)
>>  {
>>  	struct adis16480 *adis16480 = file->private_data;
>> -	char buf[6];
>> +	char buf[7];
>>  	size_t len;
>>  	u16 rev;
>>  	int ret;
>> @@ -134,7 +134,7 @@ static ssize_t adis16480_show_firmware_revision(struct file *file,
>>  	if (ret < 0)
>>  		return ret;
>>  
>> -	len = snprintf(buf, sizeof(buf), "%x.%x\n", rev >> 8, rev & 0xff);
>> +	len = scnprintf(buf, sizeof(buf), "%x.%x\n", rev >> 8, rev & 0xff);
>>  
>>  	return simple_read_from_buffer(userbuf, count, ppos, buf, len);
>>  }
> 
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