Re: [PATCH 01/10] misc: c2port: core: Ensure source size does not equal destination size in strncpy()

[Rodolfo Giometti]

On 26/06/2020 15:05, Lee Jones wrote:
> We need to ensure there's a place for the NULL terminator.
> 
> Fixes the following W=1 warning(s):
> 
>  In file included from include/linux/bitmap.h:9,
>  from include/linux/nodemask.h:95,
>  from include/linux/mmzone.h:17,
>  from include/linux/gfp.h:6,
>  from include/linux/umh.h:4,
>  from include/linux/kmod.h:9,
>  from include/linux/module.h:16,
>  from drivers/misc/c2port/core.c:9:
>  In function âstrncpyâ,
>  inlined from âc2port_device_registerâ at drivers/misc/c2port/core.c:926:2:
>  include/linux/string.h:297:30: warning: â__builtin_strncpyâ specified bound 32 equals destination size [-Wstringop-truncation]
>  297 | #define __underlying_strncpy __builtin_strncpy
>  | ^
>  include/linux/string.h:307:9: note: in expansion of macro â__underlying_strncpyâ
>  307 | return __underlying_strncpy(p, q, size);
>  | ^~~~~~~~~~~~~~~~~~~~
> 
> Cc: Rodolfo Giometti <giometti@xxxxxxxx>
> Cc: "Eurotech S.p.A" <info@xxxxxxxxxxx>
> Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx>
> ---
>  drivers/misc/c2port/core.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/misc/c2port/core.c b/drivers/misc/c2port/core.c
> index 33bba18022892..80d87e8a0bea9 100644
> --- a/drivers/misc/c2port/core.c
> +++ b/drivers/misc/c2port/core.c
> @@ -923,7 +923,7 @@ struct c2port_device *c2port_device_register(char *name,
>  	}
>  	dev_set_drvdata(c2dev->dev, c2dev);
>  
> -	strncpy(c2dev->name, name, C2PORT_NAME_LEN);
> +	strncpy(c2dev->name, name, C2PORT_NAME_LEN - 1);
>  	c2dev->ops = ops;
>  	mutex_init(&c2dev->mutex);
>  

Acked-by: Rodolfo Giometti <giometti@xxxxxxxxxxxx>

Note that giometti@xxxxxxxx is just an alias. My main e-mail address is
giometti@xxxxxxxxxxxx

Rodolfo Giometti

-- 
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