Re: [PATCH 3/4] tracing/filters: Fix MATCH_FRONT_ONLY filter matching

[Frederic Weisbecker <fweisbec@gmail.com>]

On Fri, Dec 11, 2009 at 05:59:28PM +0800, Li Zefan wrote:
> MATCH_FRONT_ONLY matching works exactly as MATCH_FULL.
> 
> We should pass the length of the pattern to strncmp().
> 
> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
> ---
>  kernel/trace/trace_events_filter.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
> index c8eb1c0..bd492ce 100644
> --- a/kernel/trace/trace_events_filter.c
> +++ b/kernel/trace/trace_events_filter.c
> @@ -262,7 +262,7 @@ static int regex_match_full(char *str, struct regex *r, int len)
>  
>  static int regex_match_front(char *str, struct regex *r, int len)
>  {
> -	if (strncmp(str, r->pattern, len) == 0)
> +	if (strncmp(str, r->pattern, r->len) == 0)
>  		return 1;
>  	return 0;
>  }


But it was working before the fix to match full.
The MATCH_FULL fix is nice but it also brings a new bug that
is fixed in this patch.

Could you perhaps rework the MATCH_FULL fix to avoid that?

Thanks.