Messages in this thread | | | Subject | Re: [PATCH 4/4] tracing/filters: Fix MATCH_EBD_ONLY filter matching | From | Steven Rostedt <> | Date | Fri, 11 Dec 2009 10:14:18 -0500 |
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On Fri, 2009-12-11 at 17:59 +0800, Li Zefan wrote: > For '*foo' pattern, we should allow any string ending with > 'foo', but tracing filter incorrectly disallows strings > matching regex expression ".*foo.*foo". > > Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> > --- > kernel/trace/trace_events_filter.c | 5 +++-- > 1 files changed, 3 insertions(+), 2 deletions(-) > > diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c > index bd492ce..9f96339 100644 > --- a/kernel/trace/trace_events_filter.c > +++ b/kernel/trace/trace_events_filter.c > @@ -276,9 +276,10 @@ static int regex_match_middle(char *str, struct regex *r, int len) > > static int regex_match_end(char *str, struct regex *r, int len) > { > - char *ptr = strstr(str, r->pattern); > + int strlen = len - 1; > > - if (ptr && (ptr[r->len] == 0)) > + if (strlen >= r->len && > + !memcmp(str + strlen - r->len, r->pattern, r->len))
Please use memcmp() == 0, I've seen too many bugs with !*cmp as well as with *cmp, because humans tend to think instinctively when reading this that ! is not a match. With "== 0" we think that "==" is a match and "!=" is a miss.
Thanks,
-- Steve
> return 1; > return 0; > }
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