Re: [PATCH] libfile: null-terminate buffer as expected

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

On 9/16/19 8:38 PM, Ahmad Fatoum wrote:
> strim calls strlen on buf internally which is undefined because buf
> is not null-terminated. Fix this.

Please dismiss... read_file_2 has its buffer allocated with calloc,
thus nothing to see here...

> 
> Accessing buf+size is safe, because read_file_2 always allocates a
> 1 byte bigger buffer than the required (non-null-terminated) size.
> 
> This leading to errors can be observed by increasing the alignment of
> the buffer allocated in read_file_2. This would lead to
> 
> 	ERROR: Cannot init param from global: ... : Invalid argument
> 
> messages whenever nvvar_load is executed.
> 
> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
> ---
>  lib/libfile.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/lib/libfile.c b/lib/libfile.c
> index 172602377fc0..92f8fc2608e5 100644
> --- a/lib/libfile.c
> +++ b/lib/libfile.c
> @@ -136,6 +136,8 @@ char *read_file_line(const char *fmt, ...)
>  	if (!buf)
>  		goto out;
>  
> +	buf[size] = '\0';
> +
>  	line = strim(buf);
>  
>  	line = xstrdup(line);
> 

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox