verifreg: Avoid re-using state between transactions (#1220)

actors/verifreg/src/lib.rs

@@ -106,7 +106,6 @@ impl Actor {
  }
 
  let verifier = resolve_to_actor_id(rt, &params.address, true)?;
-
  let verifier = Address::new_id(verifier);
 
  let st: State = rt.state()?;
@@ -138,10 +137,8 @@ impl Actor {
  let verifier = resolve_to_actor_id(rt, &params, false)?;
  let verifier = Address::new_id(verifier);
 
- let state: State = rt.state()?;
- rt.validate_immediate_caller_is(std::iter::once(&state.root_key))?;
-
  rt.transaction(|st: &mut State, rt| {
+ rt.validate_immediate_caller_is(std::iter::once(&st.root_key))?;
  st.remove_verifier(rt.store(), &verifier).context("failed to remove verifier")
  })
  }
@@ -165,39 +162,38 @@ impl Actor {
  let client = resolve_to_actor_id(rt, &params.address, true)?;
  let client = Address::new_id(client);
 
- let st: State = rt.state()?;
- if client == st.root_key {
- return Err(actor_error!(illegal_argument, "root cannot be added as client"));
- }
+ rt.transaction(|st: &mut State, rt| {
+  if client == st.root_key {
+  return Err(actor_error!(illegal_argument, "root cannot be added as client"));
+  }
 
- // Validate caller is one of the verifiers, i.e. has an allowance (even if zero).
- let verifier = rt.message().caller();
- let verifier_cap = st
- .get_verifier_cap(rt.store(), &verifier)?
- .ok_or_else(|| actor_error!(not_found, "caller {} is not a verifier", verifier))?;
+  // Validate caller is one of the verifiers, i.e. has an allowance (even if zero).
+  let verifier = rt.message().caller();
+  let verifier_cap = st
+  .get_verifier_cap(rt.store(), &verifier)?
+  .ok_or_else(|| actor_error!(not_found, "caller {} is not a verifier", verifier))?;
 
- // Disallow existing verifiers as clients.
- if st.get_verifier_cap(rt.store(), &client)?.is_some() {
- return Err(actor_error!(
- illegal_argument,
- "verifier {} cannot be added as a verified client",
- client
- ));
- }
+  // Disallow existing verifiers as clients.
+  if st.get_verifier_cap(rt.store(), &client)?.is_some() {
+  return Err(actor_error!(
+  illegal_argument,
+  "verifier {} cannot be added as a verified client",
+  client
+  ));
+  }
 
- // Compute new verifier allowance.
- if verifier_cap < params.allowance {
- return Err(actor_error!(
- illegal_argument,
- "add more DataCap {} for client than allocated {}",
- params.allowance,
- verifier_cap
- ));
- }
+  // Compute new verifier allowance.
+  if verifier_cap < params.allowance {
+  return Err(actor_error!(
+  illegal_argument,
+  "add more DataCap {} for client than allocated {}",
+  params.allowance,
+  verifier_cap
+  ));
+  }
 
- // Reduce verifier's cap.
- let new_verifier_cap = verifier_cap - &params.allowance;
- rt.transaction(|st: &mut State, rt| {
+ // Reduce verifier's cap.
+ let new_verifier_cap = verifier_cap - &params.allowance;
  st.put_verifier(rt.store(), &verifier, &new_verifier_cap)
  .context("failed to update verifier allowance")
  })?;