[PATCH] libtraceevent: Do not return a local stack pointer in get_field_str()

From: "Steven Rostedt (Google)" <[email protected]>

Jerome Marchand sent a patch with the description of:

    The function get_field_str() can return a pointer to string on the
    stack. Replace it by a global variable.

    Fixes a RETURN_LOCAL error (CWE-562)

But made hex a global variable. Having a generic name "hex" as a global
variable in a library will cause a lot of issues. Just make it a static
variable, and then it can be used outside the function.

Link: https://lore.kernel.org/linux-trace-devel/[email protected]/

Fixes: dee43d8067350 ("tools lib traceevent: Let filtering numbers by string use function names")
Reported-by: "Jerome Marchand" <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>
---
 src/parse-filter.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/parse-filter.c b/src/parse-filter.c
index e448ee2b6799..75b84a0cc4ae 100644
--- a/src/parse-filter.c
+++ b/src/parse-filter.c
@@ -1704,8 +1704,8 @@ static const char *get_field_str(struct tep_filter_arg *arg, struct tep_record *
 	struct tep_handle *tep;
 	unsigned long long addr;
 	const char *val = NULL;
+	static char hex[64];
 	unsigned int size;
-	char hex[64];
 
 	/* If the field is not a string convert it */
 	if (arg->str.field->flags & TEP_FIELD_IS_STRING) {
-- 
2.43.0