neorados: Do not try to decode an empty response in notify

The response can be empty on some errors. Attempting to decode an
empty one loses the error value on valid errors. Also swallow any
decode errors.

Signed-off-by: Adam C. Emerson <aemerson@redhat.com>
(cherry picked from commit 89134791c16a2332457cfea85321a07e9ff7ca87)
Fixes: https://tracker.ceph.com/issues/76434
Signed-off-by: Adam C. Emerson <aemerson@redhat.com>

diff --git a/src/neorados/RADOS.cc b/src/neorados/RADOS.cc
index 6aeaddbf7df175e61f1f23669fffdee454b60040..ef27c0779c6990dfeeb88861130e14b652713971 100644 (file)
--- a/src/neorados/RADOS.cc
+++ b/src/neorados/RADOS.cc
@@ -1731,11 +1731,16 @@ struct NotifyHandler : std::enable_shared_from_this<NotifyHandler> {
       ceph_assert(c);
       bc::flat_map<std::pair<uint64_t, uint64_t>, buffer::list> reply_map;
       bc::flat_set<std::pair<uint64_t, uint64_t>> missed_set;
-      auto p = rbl.cbegin();
-      decode(reply_map, p);
-      decode(missed_set, p);
-      asio::dispatch(asio::append(std::move(c), res, std::move(reply_map),
-                                 std::move(missed_set)));
+      if (rbl.length() > 0) try {
+          auto p = rbl.cbegin();
+          decode(reply_map, p);
+          decode(missed_set, p);
+      } catch (const std::exception&) {
+        // Swallowing the decode error.
+      }
+      asio::dispatch(
+          asio::append(
+              std::move(c), res, std::move(reply_map), std::move(missed_set)));
     }
   }
 };