Re: [PATCH 04/10] perf tools: Fix out-of-bound access to struct perf_session

[Arnaldo Carvalho de Melo <acme@redhat.com>]

Em Tue, Dec 06, 2011 at 11:32:34AM +0100, Robert Richter escreveu:
> If filename is NULL there is an out-of-bound access to struct
> perf_session if it would be used with perf_session__open(). Shouldn't
> actually happen in current implementation as filename is always
> !NULL. Fixing this by always null-terminating filename.

Interesting, defensive programing, ok.
 
> Signed-off-by: Robert Richter <robert.richter@amd.com>
> ---
>  tools/perf/util/session.c |    2 +-
>  tools/perf/util/session.h |    2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
> index 85c1e6b7..2ad9c10 100644
> --- a/tools/perf/util/session.c
> +++ b/tools/perf/util/session.c
> @@ -132,7 +132,7 @@ struct perf_session *perf_session__new(const char *filename, int mode,
>  				       bool force, bool repipe,
>  				       struct perf_event_ops *ops)
>  {
> -	size_t len = filename ? strlen(filename) + 1 : 0;
> +	size_t len = filename ? strlen(filename) : 0;
>  	struct perf_session *self = zalloc(sizeof(*self) + len);
>  
>  	if (self == NULL)
> diff --git a/tools/perf/util/session.h b/tools/perf/util/session.h
> index 6e393c9..f320cd5 100644
> --- a/tools/perf/util/session.h
> +++ b/tools/perf/util/session.h
> @@ -54,7 +54,7 @@ struct perf_session {
>  	char			*cwd;
>  	struct ordered_samples	ordered_samples;
>  	struct callchain_cursor	callchain_cursor;
> -	char			filename[0];
> +	char			filename[1];
>  };
>  
>  struct perf_evsel;
> -- 
> 1.7.7
>