Messages in this thread | | | Subject | Re: [Cocci] [PATCH] usb: atm: don't use snprintf() for sysfs attrs | From | Joe Perches <> | Date | Thu, 27 Aug 2020 15:11:57 -0700 |
| |
On Thu, 2020-08-27 at 22:03 +0000, David Laight wrote: > 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;
or given clang's requirement for stpcpy
return stpcpy(buf, dev_name(dev)) - buf;
(I do not advocate for this ;)
| |