pw_kvs: Fix out-of-bounds access

Change-Id: I28a56f9d4f620a858e24445efd5729ec95b6b710 Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/108225 Reviewed-by: Alexei Frolov <[email protected]> Commit-Queue: Auto-Submit <[email protected]> Pigweed-Auto-Submit: Armando Montanez <[email protected]>
google · Aug 25, 2022 · c9b6641 · c9b6641
1 parent 28e3e78
commit c9b6641
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/pw_kvs/public/pw_kvs/internal/entry_cache.h b/pw_kvs/public/pw_kvs/internal/entry_cache.h
@@ -58,8 +58,12 @@ class EntryMetadata {
   // Adds a new address to the entry metadata. MUST NOT be called more times
   // than allowed by the redundancy.
   void AddNewAddress(Address address) {
-    addresses_[addresses_.size()] = address;
+    // Each descriptor is given sufficient space in an EntryCache's address
+    // buffer to meet the redundancy requirements of an EntryCache. This object
+    // isn't aware of required redundancy, so there's no strict checking that
+    // this contract is respected.
     addresses_ = span<Address>(addresses_.begin(), addresses_.size() + 1);
+    addresses_[addresses_.size() - 1] = address;
   }
 
   // Remove an address from the entry metadata.