blockworks-foundation
/
solana
mirror of https://github.com/blockworks-foundation/solana.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

Fix bad assertion (#17401)

This commit is contained in:
carllin 2021-05-22 20:18:13 -07:00 committed by GitHub
parent cf1acfb021
commit 8664b2cc39
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 54 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

59
core/src/consensus.rs
View File

@ -715,6 +715,8 @@ impl Tower {
// then use this bank as a representative for the fork.
|| descendants.iter().any(|d| progress.get_fork_stats(*d).map(|stats| stats.computed).unwrap_or(false))
|| *candidate_slot == last_voted_slot
// Ignore if the `candidate_slot` is a descendant of the `last_voted_slot`, since we do not
// want to count votes on the same fork.
|| Self::is_candidate_slot_descendant_of_last_vote(*candidate_slot, last_voted_slot, ancestors).expect("exists in descendants map, so must exist in ancestors map")
|| *candidate_slot <= root
{
@ -776,9 +778,30 @@ impl Tower {
}
if *candidate_latest_frozen_vote > last_voted_slot
&& !Self::is_candidate_slot_descendant_of_last_vote(
&&
// Because `candidate_latest_frozen_vote` is the last vote made by some validator
// in the cluster for a frozen bank `B` observed through gossip, we may have cleared
// that frozen bank `B` because we `set_root(root)` for a `root` on a different fork,
// like so:
//
// |----------X ------candidate_latest_frozen_vote (frozen)
// old root
// |----------new root ----last_voted_slot
//
// In most cases, because `last_voted_slot` must be a descendant of `root`, then
// if `candidate_latest_frozen_vote` is not found in the ancestors/descendants map (recall these
// directly reflect the state of BankForks), this implies that `B` was pruned from BankForks
// because it was on a different fork than `last_voted_slot`, and thus this vote for `candidate_latest_frozen_vote`
// should be safe to count towards the switching proof:
//
// However, there is also the possibility that `last_voted_slot` is a stray, in which
// case we cannot make this conclusion as we do not know the ancestors/descendants
// of strays. Hence we err on the side of caution here and ignore this vote. This
// is ok because validators voting on different unrooted forks should eventually vote
// on some descendant of the root, at which time they can be included in switching proofs.
!Self::is_candidate_slot_descendant_of_last_vote(
*candidate_latest_frozen_vote, last_voted_slot, ancestors)
.expect("candidate_latest_frozen_vote is a frozen bank, so must exist in ancestors map") {
.unwrap_or(true) {
let stake = epoch_vote_accounts
.get(vote_account_pubkey)
.map(|(stake, _)| *stake)
@ -1820,7 +1843,8 @@ pub mod test {
/ (tr(44)
// Minor fork 2
/ (tr(45) / (tr(46) / (tr(47) / (tr(48) / (tr(49) / (tr(50)))))))
/ (tr(110))))));
/ (tr(110)))
/ tr(112))));
// Fill the BankForks according to the above fork structure
vote_simulator.fill_bank_forks(forks, &HashMap::new());
@ -2124,18 +2148,19 @@ pub mod test {
.latest_validator_votes_for_frozen_banks
.check_add_vote(
other_vote_account,
110,
112,
Some(
vote_simulator
.bank_forks
.read()
.unwrap()
.get(110)
.get(112)
.unwrap()
.hash(),
),
false,
);
assert_eq!(
tower.check_switch_threshold(
110,
@ -2148,6 +2173,30 @@ pub mod test {
),
SwitchForkDecision::SwitchProof(Hash::default())
);
// If we now set a root that causes slot 112 to be purged from BankForks, then
// the switch proof will now fail since that validator's vote can no longer be
// included in the switching proof
vote_simulator.set_root(44);
let ancestors = vote_simulator.bank_forks.read().unwrap().ancestors();
let descendants = vote_simulator
.bank_forks
.read()
.unwrap()
.descendants()
.clone();
assert_eq!(
tower.check_switch_threshold(
110,
&ancestors,
&descendants,
&vote_simulator.progress,
total_stake,
bank0.epoch_vote_accounts(0).unwrap(),
&vote_simulator.latest_validator_votes_for_frozen_banks
),
SwitchForkDecision::FailedSwitchThreshold(0, 20000)
);
}
#[test]