Return injected error when injecting empty result and corrupted bytes…

… read error (#13369)

Summary:
**Context/Summary:**

archang19 found the place in code where no injected error status is returned on effectively injected error (empty result or corrupted bytes). I can't find a good argument for doing so. In these cases where such empty result and corrupted result is not expected, the file system should return error (< 0). Our fault injection framework should align with that to simulate fault returned by file system.

Pull Request resolved: #13369

Test Plan: Monitor stress test

Reviewed By: archang19

Differential Revision: D69136015

Pulled By: hx235

fbshipit-source-id: 6ee7a7bd5e0aa19837e4dfd73817d4a9d5af76f9

utilities/fault_injection_fs.cc

@@ -1412,6 +1412,7 @@ IOStatus FaultInjectionTestFS::MaybeInjectThreadLocalReadError(
       msg << "empty result";
       ctx->message = msg.str();
       ret_fault_injected = true;
+      ret = IOStatus::IOError(ctx->message);
     } else if (!direct_io && Random::GetTLSInstance()->OneIn(7) &&
                scratch != nullptr && result->data() == scratch) {
       assert(result);
@@ -1430,6 +1431,7 @@ IOStatus FaultInjectionTestFS::MaybeInjectThreadLocalReadError(
       msg << "corrupt last byte";
       ctx->message = msg.str();
       ret_fault_injected = true;
+      ret = IOStatus::IOError(ctx->message);
     } else {
       msg << "error result multiget single";
       ctx->message = msg.str();