On Fri, Jan 12, 2018 at 1:46 PM, Xiongfeng Wang
<wangxiongfeng2@xxxxxxxxxx> wrote:
> From: Xiongfeng Wang <xiongfeng.wang@xxxxxxxxxx>
>
> drivers/message/fusion/mptctl.c: In function '__mptctl_ioctl.isra.3':
> ./include/linux/string.h:245:9: warning: '__builtin_strncpy' specified
> bound 12 equals destination size [-Wstringop-truncation]
>
> The compiler requires that the destination size should be greater than
> the length we copy to make sure the dest string is nul-terminated. We
> can just use strlcpy() to avoid this warning.
Are you sure it's a best approach in this case?
> - strncpy (karg->driverVersion, MPT_LINUX_PACKAGE_NAME, MPT_IOCTL_VERSION_LENGTH);
> - karg->driverVersion[MPT_IOCTL_VERSION_LENGTH-1]='\0';
> + strlcpy (karg->driverVersion, MPT_LINUX_PACKAGE_NAME, MPT_IOCTL_VERSION_LENGTH);
This one is false positive.
> - strncpy (karg.name, ioc->name, MPT_MAX_NAME);
> - karg.name[MPT_MAX_NAME-1]='\0';
> - strncpy (karg.product, ioc->prod_name, MPT_PRODUCT_LENGTH);
> - karg.product[MPT_PRODUCT_LENGTH-1]='\0';
> + strlcpy (karg.name, ioc->name, MPT_MAX_NAME);
> + strlcpy (karg.product, ioc->prod_name, MPT_PRODUCT_LENGTH);
These two as well.
> - strncpy(karg.serial_number, " ", 24);
> + strlcpy(karg.serial_number, " ", 24);
This one is interesting indeed.
Though the fix would be rather something like
memset(&karg.serial_number, " ", 24); // leave 24 for best performance of memset
karg.serial_number[24-1] = '\0';
> if (mpt_config(ioc, &cfg) == 0) {
> ManufacturingPage0_t *pdata = (ManufacturingPage0_t *) pbuf;
> if (strlen(pdata->BoardTracerNumber) > 1) {
> - strncpy(karg.serial_number, pdata->BoardTracerNumber, 24);
> - karg.serial_number[24-1]='\0';
> + strlcpy(karg.serial_number,
> + pdata->BoardTracerNumber, 24);
> }
...and here you don't need to touch anything.
--
With Best Regards,
Andy Shevchenko
