kernel: fix out of bound reading. close #1227

tiann · Dec 27, 2023 · d6cbda4 · d6cbda4
1 parent fe7f509
commit d6cbda4
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/kernel/allowlist.c b/kernel/allowlist.c
@@ -458,7 +458,9 @@ void ksu_prune_allowlist(bool (*is_uid_valid)(uid_t, char *, void *), void *data
 			modified = true;
 			pr_info("prune uid: %d, package: %s\n", uid, package);
 			list_del(&np->list);
-			allow_list_bitmap[uid / BITS_PER_BYTE] &= ~(1 << (uid % BITS_PER_BYTE));
+			if (likely(uid <= BITMAP_UID_MAX)) {
+				allow_list_bitmap[uid / BITS_PER_BYTE] &= ~(1 << (uid % BITS_PER_BYTE));
+			}
 			remove_uid_from_arr(uid);
 			smp_mb();
 			kfree(np);