Re: Patch "tracing: Have filter check for balanced ops" has been added to the 3.14-stable tree

[Jiri Slaby <jslaby@suse.cz>]

On 06/23/2015, 05:22 AM, gregkh@linuxfoundation.org wrote:
> 
> This is a note to let you know that I've just added the patch titled
> 
>     tracing: Have filter check for balanced ops
> 
> to the 3.14-stable tree which can be found at:
>     http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
> 
> The filename of the patch is:
>      tracing-have-filter-check-for-balanced-ops.patch
> and it can be found in the queue-3.14 subdirectory.
> 
> If you, or anyone else, feels it should not be added to the stable tree,
> please let <stable@vger.kernel.org> know about it.
> 
> 
> From 2cf30dc180cea808077f003c5116388183e54f9e Mon Sep 17 00:00:00 2001
> From: Steven Rostedt <rostedt@goodmis.org>
> Date: Mon, 15 Jun 2015 17:50:25 -0400
> Subject: tracing: Have filter check for balanced ops
> 
> From: Steven Rostedt <rostedt@goodmis.org>
> 
> commit 2cf30dc180cea808077f003c5116388183e54f9e upstream.

...

> --- a/kernel/trace/trace_events_filter.c
> +++ b/kernel/trace/trace_events_filter.c
> @@ -1399,19 +1399,26 @@ static int check_preds(struct filter_par
>  {
>  	int n_normal_preds = 0, n_logical_preds = 0;
>  	struct postfix_elt *elt;
> +	int cnt = 0;
>  
>  	list_for_each_entry(elt, &ps->postfix, list) {
> -		if (elt->op == OP_NONE)
> +		if (elt->op == OP_NONE) {
> +			cnt++;
>  			continue;
> +		}
>  
>  		if (elt->op == OP_AND || elt->op == OP_OR) {
>  			n_logical_preds++;
> +			cnt--;
>  			continue;
>  		}
> +		if (elt->op != OP_NOT)

This breaks build, OP_NOT is not in 3.14 (or 3.10) yet. I dropped this
line for 3.12.

> +			cnt--;
>  		n_normal_preds++;
> +		WARN_ON_ONCE(cnt < 0);
>  	}
>  
> -	if (!n_normal_preds || n_logical_preds >= n_normal_preds) {
> +	if (cnt != 1 || !n_normal_preds || n_logical_preds >= n_normal_preds) {
>  		parse_error(ps, FILT_ERR_INVALID_FILTER, 0);
>  		return -EINVAL;
>  	}
> 
> 

thanks,
-- 
js
suse labs