ftrace: Fix MATCH_END_ONLY function filter
For '*foo' pattern, we should allow any string ending with
'foo', but ftrace filter incorrectly disallows strings
like bar_foo_foo:
# echo '*io' > set_ftrace_filter
# cat set_ftrace_filter | grep 'req_bio_endio'
# cat available_filter_functions | grep 'req_bio_endio'
req_bio_endio
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4B4E870E.6060607@cn.fujitsu.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 7968762..1e6640f 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1690,7 +1690,7 @@
static int ftrace_match(char *str, char *regex, int len, int type)
{
int matched = 0;
- char *ptr;
+ int slen;
switch (type) {
case MATCH_FULL:
@@ -1706,8 +1706,8 @@
matched = 1;
break;
case MATCH_END_ONLY:
- ptr = strstr(str, regex);
- if (ptr && (ptr[len] == 0))
+ slen = strlen(str);
+ if (slen >= len && memcmp(str + slen - len, regex, len) == 0)
matched = 1;
break;
}
