Re: [PATCH 1/1] Char: ipmi_bt_sm, fix infinite loop

[Corey Minyard <minyard@acm.org>]

Looks right to me.  Rocky, copying you in case there's an issue with this.

Thanks,

-corey

On 02/25/2014 04:14 AM, Jiri Slaby wrote:
> In read_all_bytes, we do
>   unsigned char i;
> ...
>   bt->read_data[0] = BMC2HOST;
>   bt->read_count = bt->read_data[0];
> ...
>   for (i = 1; i <= bt->read_count; i++)
>     bt->read_data[i] = BMC2HOST;
>
> If bt->read_data[0] == bt->read_count == 255, we loop infinitely in
> the 'for' loop. Make 'i' an 'int' instead of 'char' to get rid of the
> overflow and finish the loop after 255 iterations every time.
>
> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
> Reported-and-debugged-by: Rui Hui Dian <rhdian@novell.com>
> Cc: Tomas Cech <tcech@suse.cz>
> Cc: Corey Minyard <minyard@acm.org>
> Cc: <openipmi-developer@lists.sourceforge.net>
> ---
>  drivers/char/ipmi/ipmi_bt_sm.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/char/ipmi/ipmi_bt_sm.c b/drivers/char/ipmi/ipmi_bt_sm.c
> index f5e4cd7617f6..61e71616689b 100644
> --- a/drivers/char/ipmi/ipmi_bt_sm.c
> +++ b/drivers/char/ipmi/ipmi_bt_sm.c
> @@ -352,7 +352,7 @@ static inline void write_all_bytes(struct si_sm_data *bt)
>  
>  static inline int read_all_bytes(struct si_sm_data *bt)
>  {
> -	unsigned char i;
> +	unsigned int i;
>  
>  	/*
>  	 * length is "framing info", minimum = 4: NetFn, Seq, Cmd, cCode.