RE: [Cocci] [PATCH] usb: atm: don't use snprintf() for sysfs attrs

[David Laight]

From: Joe Perches
> Sent: 27 August 2020 21:30
...
> Perhaps what's necessary is to find any
> appropriate .show function and change
> any use of strcpy/sprintf within those
> function to some other name.
> 
> For instance:
> 
> drivers/isdn/mISDN/core.c-static ssize_t name_show(struct device *dev,
> drivers/isdn/mISDN/core.c-                       struct device_attribute *attr, char *buf)
> drivers/isdn/mISDN/core.c-{
> drivers/isdn/mISDN/core.c:      strcpy(buf, dev_name(dev));
> drivers/isdn/mISDN/core.c-      return strlen(buf);
> drivers/isdn/mISDN/core.c-}
> drivers/isdn/mISDN/core.c-static DEVICE_ATTR_RO(name);

That form ends up calculating the string length twice.
Better would be:
	len = strlen(msg);
	memcpy(buf, msg, len);
	return len;


	David

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