During the investigation of scylladb/scylladb#20282, it was discovered that implementations of speculating read executors have undefined behavior when called with an incorrect number of read replicas. This PR introduces two levels of condition checking:
- Condition checking in speculating read executors for the number of replicas.
- Checking the consistency of the Effective Replication Map in filter_for_query(): the map is considered incorrect if the list of replicas contains a node from a data center whose replication factor is 0.
Please note: This PR does not fix the issue found in scylladb/scylladb#20282; it only adds condition checks to prevent undefined behavior in cases of inconsistent inputs.
Refs scylladb/scylladb#20625
As this issue applies to the releases versions and can affect clients, we need backports to 6.0, 6.1, 6.2.
(cherry picked from commit 132358dc92)
(cherry picked from commit ae23d42889)
(cherry picked from commit ad93cf5753)
(cherry picked from commit 8db6d6bd57)
(cherry picked from commit c373edab2d)
Refs #20851Closesscylladb/scylladb#21067
* github.com:scylladb/scylladb:
Add conditions checking for get_read_executor
Avoid an extra call to block_for in db::filter_for_query.
Improve code readability in consistency_level.cc and storage_proxy.cc
tools: Add build_info header with functions providing build type information
tests: Add tests for alter table with RF=1 to RF=0
85b1c64a33