Re: [PATCH] hamradio: dmascc: avoid -Wformat-overflow warning

From: David Miller
Date: Wed Jul 26 2017 - 12:41:46 EST


From: Arnd Bergmann <arnd@xxxxxxxx>
Date: Wed, 26 Jul 2017 09:55:33 +0200

> gcc warns that the device name might overflow:
>
> drivers/net/hamradio/dmascc.c: In function 'dmascc_init':
> drivers/net/hamradio/dmascc.c:584:22: error: 'sprintf' may write a terminating nul past the end of the destination [-Werror=format-overflow=]
> sprintf(dev->name, "dmascc%i", 2 * n + i);
> drivers/net/hamradio/dmascc.c:584:3: note: 'sprintf' output between 8 and 17 bytes into a destination of size 16
> sprintf(dev->name, "dmascc%i", 2 * n + i);
>
> From the static data in this file, I can tell that the index is
> strictly limited to 16, so it won't overflow. This simply changes
> the sprintf() to snprintf(), which is a good idea in general,
> and shuts up this warning.
>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

Applied to net-next.