[PATCH v4 8/8] kunit: validate glob filter patterns before use

[Josh Law <objecting@objecting.org>]

kunit_parse_glob_filter() accepts user-provided glob patterns via the
filter_glob module parameter but does not check whether they are
well-formed.  A malformed pattern like "suite[.test" (unclosed bracket)
or "suite\" (trailing backslash) is silently passed to glob_match()
which handles it gracefully but not in the way the user likely intended
— the bracket is matched as a literal character rather than starting a
character class.

Use glob_validate() to reject malformed patterns early with -EINVAL,
so users get a clear error instead of silently wrong filter results.

Signed-off-by: Josh Law <objecting@objecting.org>
---
 lib/kunit/executor.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/lib/kunit/executor.c b/lib/kunit/executor.c
index 1fef217de11d..f0cc15e4b34d 100644
--- a/lib/kunit/executor.c
+++ b/lib/kunit/executor.c
@@ -91,6 +91,8 @@ static int kunit_parse_glob_filter(struct kunit_glob_filter *parsed,
 	const char *period = strchr(filter_glob, '.');
 
 	if (!period) {
+		if (!glob_validate(filter_glob))
+			return -EINVAL;
 		parsed->suite_glob = kstrdup(filter_glob, GFP_KERNEL);
 		if (!parsed->suite_glob)
 			return -ENOMEM;
@@ -102,12 +104,23 @@ static int kunit_parse_glob_filter(struct kunit_glob_filter *parsed,
 	if (!parsed->suite_glob)
 		return -ENOMEM;
 
+	if (!glob_validate(parsed->suite_glob)) {
+		kfree(parsed->suite_glob);
+		return -EINVAL;
+	}
+
 	parsed->test_glob = kstrdup(period + 1, GFP_KERNEL);
 	if (!parsed->test_glob) {
 		kfree(parsed->suite_glob);
 		return -ENOMEM;
 	}
 
+	if (!glob_validate(parsed->test_glob)) {
+		kfree(parsed->test_glob);
+		kfree(parsed->suite_glob);
+		return -EINVAL;
+	}
+
 	return 0;
 }
 
-- 
2.34.1