Re: [PATCH] fdt: copy terminating '\0' in lstrcpy()

[Sascha Hauer <sha@pengutronix.de>]

On Wed, Jul 19, 2023 at 08:11:29PM +0200, Enrico Scholz wrote:
> From: Enrico Scholz <enrico.scholz@sigma-chemnitz.de>
> 
> On large string tables (>64K), a
> 
> |		fdt->strings = realloc(fdt->strings, fdt->str_size * 2);
> 
> operation is executed.  This 'realloc()' does not zero the memory so
> there is no guarantee that the strings will be terminated properly.
> 
> Modify 'lstrcpy()' so that it also copies the terminating '\0'.
> 
> Signed-off-by: Enrico Scholz <enrico.scholz@sigma-chemnitz.de>
> ---
>  drivers/of/fdt.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)

Applied, thanks

Sascha

> 
> diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
> index 01d7dc37439f..9d72fafd3669 100644
> --- a/drivers/of/fdt.c
> +++ b/drivers/of/fdt.c
> @@ -302,15 +302,15 @@ static int lstrcpy(char *dest, const char *src)
>  	int len = 0;
>  	int maxlen = 1023;
>  
> -	while (*src) {
> -		*dest++ = *src++;
> +	do {
> +		*dest++ = *src;
>  		len++;
>  		if (!maxlen)
>  			return -ENOSPC;
>  		maxlen--;
> -	}
> +	} while (*src++);
>  
> -	return len;
> +	return len - 1;
>  }
>  
>  static void *memalign_realloc(void *orig, size_t oldsize, size_t newsize)
> -- 
> 2.41.0
> 
> 
> 

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