diff --git a/git-compat-util.h b/git-compat-util.h
index 8809776407..4bf569f35c 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -975,6 +975,26 @@ static inline int strtoul_ui(char const *s, int base, unsigned int *result)
 	return 0;
 }
 
+/*
+ * Convert a string to an unsigned long using the standard library's strtoul,
+ * with additional error handling to ensure robustness.
+ */
+static inline int strtoul_ul(char const *s, int base, unsigned long *result)
+{
+	unsigned long ul;
+	char *p;
+
+	errno = 0;
+	/* negative values would be accepted by strtoul */
+	if (strchr(s, '-'))
+		return -1;
+	ul = strtoul(s, &p, base);
+	if (errno || *p || p == s)
+		return -1;
+	*result = ul;
+	return 0;
+}
+
 static inline int strtol_i(char const *s, int base, int *result)
 {
 	long ul;