depmod: Prevent undefined behavior

Calling qsort with NULL argument is invalid, although size 0 would prevent anything bad from happening. Make sure that UBSAN is not triggered. Signed-off-by: Tobias Stoeckmann <[email protected]>
kmod-project · Oct 18, 2024 · 2261971 · 2261971
1 parent 20cc140
commit 2261971
Showing 1 changed file with 8 additions and 5 deletions.
diff --git a/tools/depmod.c b/tools/depmod.c
@@ -1494,10 +1494,12 @@ static void depmod_modules_sort(struct depmod *depmod)
 		mod->sort_idx = i++;
 	}
 
-	array_sort(&depmod->modules, mod_cmp);
-	for (idx = 0; idx < depmod->modules.count; idx++) {
-		struct mod *m = depmod->modules.array[idx];
-		m->idx = idx;
+	if (depmod->modules.count > 0) {
+		array_sort(&depmod->modules, mod_cmp);
+		for (idx = 0; idx < depmod->modules.count; idx++) {
+			struct mod *m = depmod->modules.array[idx];
+			m->idx = idx;
+		}
 	}
 
 corrupted:
@@ -2024,7 +2026,8 @@ static bool mod_get_all_sorted_dependencies(const struct mod *mod, struct array
 	if (mod_fill_all_unique_dependencies(mod, array) < 0)
 		return false;
 
-	array_sort(array, dep_cmp);
+	if (array->count > 1)
+		array_sort(array, dep_cmp);
 	return true;
 }