use custom VoteState parser everywhere

programs/vote/src/vote_state/mod.rs

@@ -854,9 +854,7 @@ pub fn authorize<S: std::hash::BuildHasher>(
     clock: &Clock,
     feature_set: &FeatureSet,
 ) -> Result<(), InstructionError> {
-    let mut vote_state: VoteState = vote_account
-        .get_state::<VoteStateVersions>()?
-        .convert_to_current();
+    let mut vote_state = VoteState::deserialize(vote_account.get_data())?;
 
     match vote_authorize {
         VoteAuthorize::Voter => {
@@ -897,9 +895,7 @@ pub fn update_validator_identity<S: std::hash::BuildHasher>(
     signers: &HashSet<Pubkey, S>,
     feature_set: &FeatureSet,
 ) -> Result<(), InstructionError> {
-    let mut vote_state: VoteState = vote_account
-        .get_state::<VoteStateVersions>()?
-        .convert_to_current();
+    let mut vote_state = VoteState::deserialize(vote_account.get_data())?;
 
     // current authorized withdrawer must say "yay"
     verify_authorized_signer(&vote_state.authorized_withdrawer, signers)?;
@@ -926,8 +922,8 @@ pub fn update_commission<S: std::hash::BuildHasher>(
 
     let enforce_commission_update_rule =
         if feature_set.is_active(&feature_set::allow_commission_decrease_at_any_time::id()) {
-            if let Ok(decoded_vote_state) = vote_account.get_state::<VoteStateVersions>() {
-                vote_state = Some(decoded_vote_state.convert_to_current());
+            if let Ok(decoded_vote_state) = VoteState::deserialize(vote_account.get_data()) {
+                vote_state = Some(decoded_vote_state);
                 is_commission_increase(vote_state.as_ref().unwrap(), commission)
             } else {
                 true
@@ -948,9 +944,7 @@ pub fn update_commission<S: std::hash::BuildHasher>(
 
     let mut vote_state = match vote_state {
         Some(vote_state) => vote_state,
-        None => vote_account
-            .get_state::<VoteStateVersions>()?
-            .convert_to_current(),
+        None => VoteState::deserialize(vote_account.get_data())?,
     };
 
     // current authorized withdrawer must say "yay"
@@ -1007,9 +1001,7 @@ pub fn withdraw<S: std::hash::BuildHasher>(
 ) -> Result<(), InstructionError> {
     let mut vote_account = instruction_context
         .try_borrow_instruction_account(transaction_context, vote_account_index)?;
-    let vote_state: VoteState = vote_account
-        .get_state::<VoteStateVersions>()?
-        .convert_to_current();
+    let vote_state = VoteState::deserialize(vote_account.get_data())?;
 
     verify_authorized_signer(&vote_state.authorized_withdrawer, signers)?;
 
@@ -1071,9 +1063,9 @@ pub fn initialize_account<S: std::hash::BuildHasher>(
     {
         return Err(InstructionError::InvalidAccountData);
     }
-    let versioned = vote_account.get_state::<VoteStateVersions>()?;
 
-    if !versioned.is_uninitialized() {
+    let vote_state = VoteState::deserialize(vote_account.get_data())?;
+    if !vote_state.is_uninitialized() {
         return Err(InstructionError::AccountAlreadyInitialized);
     }
 
@@ -1088,13 +1080,11 @@ fn verify_and_get_vote_state<S: std::hash::BuildHasher>(
     clock: &Clock,
     signers: &HashSet<Pubkey, S>,
 ) -> Result<VoteState, InstructionError> {
-    let versioned = vote_account.get_state::<VoteStateVersions>()?;
-
-    if versioned.is_uninitialized() {
+    let mut vote_state = VoteState::deserialize(vote_account.get_data())?;
+    if vote_state.is_uninitialized() {
         return Err(InstructionError::UninitializedAccount);
     }
 
-    let mut vote_state = versioned.convert_to_current();
     let authorized_voter = vote_state.get_and_update_authorized_voter(clock.epoch)?;
     verify_authorized_signer(&authorized_voter, signers)?;
 

sdk/program/src/vote/authorized_voters.rs

@@ -65,6 +65,11 @@ impl AuthorizedVoters {
         self.authorized_voters.is_empty()
     }
 
+    // when an uninitialized V0_23_5 account is converted to current, it inserts a null voter
+    pub fn is_uninitialized(&self) -> bool {
+        self.is_empty() || (self.len() == 1 && self.first() == Some((&0, &Pubkey::default())))
+    }
+
     pub fn first(&self) -> Option<(&u64, &Pubkey)> {
         self.authorized_voters.iter().next()
     }

sdk/program/src/vote/state/mod.rs

@@ -1,7 +1,5 @@
 //! Vote state
 
-#[cfg(not(target_os = "solana"))]
-use bincode::deserialize;
 #[cfg(test)]
 use {
     crate::epoch_schedule::MAX_LEADER_SCHEDULE_EPOCH_OFFSET,
@@ -18,7 +16,7 @@ use {
         sysvar::clock::Clock,
         vote::{authorized_voters::AuthorizedVoters, error::VoteError},
     },
-    bincode::{serialize_into, serialized_size, ErrorKind},
+    bincode::{serialize_into, ErrorKind},
     serde_derive::{Deserialize, Serialize},
     std::{collections::VecDeque, fmt::Debug, io::Cursor},
 };
@@ -475,50 +473,50 @@ impl VoteState {
         3762 // see test_vote_state_size_of.
     }
 
-    // we retain bincode deserialize for not(target_os = "solana")
-    // because the hand-written parser does not support V0_23_5
+    /// Deserializes the input buffer into a newly allocated `VoteState`
+    ///
+    /// This function is intended as a drop-in replacement for `bincode::deserialize()`.
+    /// V0_23_5 is not supported in a BPF context, but all versions are supported on non-BPF.
     pub fn deserialize(input: &[u8]) -> Result<Self, InstructionError> {
-        #[cfg(not(target_os = "solana"))]
-        {
-            deserialize::<VoteStateVersions>(input)
-                .map(|versioned| versioned.convert_to_current())
-                .map_err(|_| InstructionError::InvalidAccountData)
-        }
-        #[cfg(target_os = "solana")]
-        {
-            let mut vote_state = Self::default();
-            Self::deserialize_into(input, &mut vote_state)?;
-            Ok(vote_state)
-        }
+        let mut vote_state = Self::default();
+        Self::deserialize_into(input, &mut vote_state)?;
+        Ok(vote_state)
     }
 
     /// Deserializes the input buffer into the provided `VoteState`
     ///
-    /// This function exists to deserialize `VoteState` in a BPF context without going above
-    /// the compute limit, and must be kept up to date with `bincode::deserialize`.
+    /// This function is exposed to allow deserialization in a BPF context directly into boxed memory.
     pub fn deserialize_into(
         input: &[u8],
         vote_state: &mut VoteState,
     ) -> Result<(), InstructionError> {
-        let minimum_size =
-            serialized_size(vote_state).map_err(|_| InstructionError::InvalidAccountData)?;
-        if (input.len() as u64) < minimum_size {
-            return Err(InstructionError::InvalidAccountData);
-        }
-
         let mut cursor = Cursor::new(input);
 
         let variant = read_u32(&mut cursor)?;
         match variant {
-            // V0_23_5. not supported; these should not exist on mainnet
-            0 => Err(InstructionError::InvalidAccountData),
+            // V0_23_5. not supported for bpf targets; these should not exist on mainnet
+            // supported for non-bpf targets for backwards compatibility
+            0 => {
+                #[cfg(not(target_os = "solana"))]
+                {
+                    *vote_state = bincode::deserialize::<VoteStateVersions>(input)
+                        .map(|versioned| versioned.convert_to_current())
+                        .map_err(|_| InstructionError::InvalidAccountData)?;
+
+                    Ok(())
+                }
+                #[cfg(target_os = "solana")]
+                Err(InstructionError::InvalidAccountData)
+            }
             // V1_14_11. substantially different layout and data from V0_23_5
             1 => deserialize_vote_state_into(&mut cursor, vote_state, false),
             // Current. the only difference from V1_14_11 is the addition of a slot-latency to each vote
             2 => deserialize_vote_state_into(&mut cursor, vote_state, true),
             _ => Err(InstructionError::InvalidAccountData),
         }?;
 
+        // if cursor overruns the input, it produces 0 values and continues to advance `position`
+        // this check ensures we do not accept such a malformed input erroneously
         if cursor.position() > input.len() as u64 {
             return Err(InstructionError::InvalidAccountData);
         }
@@ -888,6 +886,10 @@ impl VoteState {
         data.len() == VoteState::size_of()
             && data[VERSION_OFFSET..DEFAULT_PRIOR_VOTERS_END] != [0; DEFAULT_PRIOR_VOTERS_OFFSET]
     }
+
+    pub fn is_uninitialized(&self) -> bool {
+        self.authorized_voters.is_uninitialized()
+    }
 }
 
 pub mod serde_compact_vote_state_update {
@@ -1087,7 +1089,7 @@ pub mod serde_tower_sync {
 
 #[cfg(test)]
 mod tests {
-    use {super::*, itertools::Itertools, rand::Rng};
+    use {super::*, bincode::serialized_size, itertools::Itertools, rand::Rng};
 
     #[test]
     fn test_vote_serialize() {
@@ -1107,14 +1109,13 @@ mod tests {
     }
 
     #[test]
-    fn test_vote_deserialize_into() {
+    fn test_vote_deserialize() {
         // base case
         let target_vote_state = VoteState::default();
         let vote_state_buf =
             bincode::serialize(&VoteStateVersions::new_current(target_vote_state.clone())).unwrap();
 
-        let mut test_vote_state = VoteState::default();
-        VoteState::deserialize_into(&vote_state_buf, &mut test_vote_state).unwrap();
+        let test_vote_state = VoteState::deserialize(&vote_state_buf).unwrap();
 
         assert_eq!(target_vote_state, test_vote_state);
 
@@ -1130,31 +1131,40 @@ mod tests {
             let vote_state_buf = bincode::serialize(&target_vote_state_versions).unwrap();
             let target_vote_state = target_vote_state_versions.convert_to_current();
 
-            let mut test_vote_state = VoteState::default();
-            VoteState::deserialize_into(&vote_state_buf, &mut test_vote_state).unwrap();
+            let test_vote_state = VoteState::deserialize(&vote_state_buf).unwrap();
 
             assert_eq!(target_vote_state, test_vote_state);
         }
     }
 
     #[test]
-    fn test_vote_deserialize_into_nopanic() {
+    fn test_vote_deserialize_nopanic() {
         // base case
-        let mut test_vote_state = VoteState::default();
-        let e = VoteState::deserialize_into(&[], &mut test_vote_state).unwrap_err();
+        let e = VoteState::deserialize(&[]).unwrap_err();
         assert_eq!(e, InstructionError::InvalidAccountData);
 
         // variant
-        let serialized_len_x4 = serialized_size(&test_vote_state).unwrap() * 4;
+        let serialized_len_x4 = serialized_size(&VoteState::default()).unwrap() * 4;
         let mut rng = rand::thread_rng();
         for _ in 0..1000 {
             let raw_data_length = rng.gen_range(1..serialized_len_x4);
-            let raw_data: Vec<u8> = (0..raw_data_length).map(|_| rng.gen::<u8>()).collect();
+            let mut raw_data: Vec<u8> = (0..raw_data_length).map(|_| rng.gen::<u8>()).collect();
+
+            // pure random data will ~never have a valid enum tag, so lets help it out
+            if raw_data_length >= 4 && rng.gen::<bool>() {
+                let tag = rng.gen::<u8>() % 3;
+                raw_data[0] = tag;
+                raw_data[1] = 0;
+                raw_data[2] = 0;
+                raw_data[3] = 0;
+            }
 
             // it is extremely improbable, though theoretically possible, for random bytes to be syntactically valid
-            // so we only check that the deserialize function does not panic
-            let mut test_vote_state = VoteState::default();
-            let _ = VoteState::deserialize_into(&raw_data, &mut test_vote_state);
+            // so we only check that the parser does not panic and that it succeeds or fails exactly in line with bincode
+            let test_res = VoteState::deserialize(&raw_data);
+            let bincode_res = bincode::deserialize::<VoteStateVersions>(&raw_data);
+
+            assert_eq!(test_res.is_ok(), bincode_res.is_ok());
         }
     }
 

sdk/program/src/vote/state/vote_state_0_23_5.rs

@@ -1,9 +1,12 @@
 #![allow(clippy::arithmetic_side_effects)]
 use super::*;
+#[cfg(test)]
+use arbitrary::{Arbitrary, Unstructured};
 
 const MAX_ITEMS: usize = 32;
 
 #[derive(Debug, Default, Serialize, Deserialize, PartialEq, Eq, Clone)]
+#[cfg_attr(test, derive(Arbitrary))]
 pub struct VoteState0_23_5 {
     /// the node that votes in this account
     pub node_pubkey: Pubkey,
@@ -59,3 +62,59 @@ impl<I> CircBuf<I> {
         self.buf[self.idx] = item;
     }
 }
+
+#[cfg(test)]
+impl<'a, I: Default + Copy> Arbitrary<'a> for CircBuf<I>
+where
+    I: Arbitrary<'a>,
+{
+    fn arbitrary(u: &mut Unstructured<'a>) -> arbitrary::Result<Self> {
+        let mut circbuf = Self::default();
+
+        let len = u.arbitrary_len::<I>()?;
+        for _ in 0..len {
+            circbuf.append(I::arbitrary(u)?);
+        }
+
+        Ok(circbuf)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_vote_deserialize_0_23_5() {
+        // base case
+        let target_vote_state = VoteState0_23_5::default();
+        let target_vote_state_versions = VoteStateVersions::V0_23_5(Box::new(target_vote_state));
+        let vote_state_buf = bincode::serialize(&target_vote_state_versions).unwrap();
+
+        let test_vote_state = VoteState::deserialize(&vote_state_buf).unwrap();
+
+        assert_eq!(
+            target_vote_state_versions.convert_to_current(),
+            test_vote_state
+        );
+
+        // variant
+        // provide 4x the minimum struct size in bytes to ensure we typically touch every field
+        let struct_bytes_x4 = std::mem::size_of::<VoteState0_23_5>() * 4;
+        for _ in 0..100 {
+            let raw_data: Vec<u8> = (0..struct_bytes_x4).map(|_| rand::random::<u8>()).collect();
+            let mut unstructured = Unstructured::new(&raw_data);
+
+            let arbitrary_vote_state = VoteState0_23_5::arbitrary(&mut unstructured).unwrap();
+            let target_vote_state_versions =
+                VoteStateVersions::V0_23_5(Box::new(arbitrary_vote_state));
+
+            let vote_state_buf = bincode::serialize(&target_vote_state_versions).unwrap();
+            let target_vote_state = target_vote_state_versions.convert_to_current();
+
+            let test_vote_state = VoteState::deserialize(&vote_state_buf).unwrap();
+
+            assert_eq!(target_vote_state, test_vote_state);
+        }
+    }
+}

sdk/program/src/vote/state/vote_state_1_14_11.rs

@@ -61,6 +61,10 @@ impl VoteState1_14_11 {
         data.len() == VoteState1_14_11::size_of()
             && data[VERSION_OFFSET..DEFAULT_PRIOR_VOTERS_END] != [0; DEFAULT_PRIOR_VOTERS_OFFSET]
     }
+
+    pub fn is_uninitialized(&self) -> bool {
+        self.authorized_voters.is_uninitialized()
+    }
 }
 
 impl From<VoteState> for VoteState1_14_11 {