Nonce accounts must be writeable (#21260)

* Nonce accounts must be writeable

* feedback

* feedback

sdk/src/feature_set.rs

@@ -237,6 +237,10 @@ pub mod reject_deployment_of_unresolved_syscalls {
     solana_sdk::declare_id!("DqniU3MfvdpU3yhmNF1RKeaM5TZQELZuyFGosASRVUoy");
 }
 
+pub mod nonce_must_be_writable {
+    solana_sdk::declare_id!("BiCU7M5w8ZCMykVSyhZ7Q3m2SWoR2qrEQ86ERcDX77ME");
+}
+
 lazy_static! {
     /// Map of feature identifiers to user-visible description
     pub static ref FEATURE_NAMES: HashMap<Pubkey, &'static str> = [
@@ -291,6 +295,7 @@ lazy_static! {
         (disable_fee_calculator::id(), "deprecate fee calculator"),
         (add_compute_budget_program::id(), "Add compute_budget_program"),
         (reject_deployment_of_unresolved_syscalls::id(), "Reject deployment of programs with unresolved syscall symbols"),
+        (nonce_must_be_writable::id(), "nonce must be writable"),
         /*************** ADD NEW FEATURES HERE ***************/
     ]
     .iter()

sdk/src/transaction/mod.rs

@@ -502,14 +502,23 @@ pub fn uses_durable_nonce(tx: &Transaction) -> Option<&CompiledInstruction> {
     message
         .instructions
         .get(NONCED_TX_MARKER_IX_INDEX as usize)
-        .filter(|maybe_ix| {
-            let prog_id_idx = maybe_ix.program_id_index as usize;
-            match message.account_keys.get(prog_id_idx) {
-                Some(program_id) => system_program::check_id(program_id),
-                _ => false,
-            }
-        } && matches!(limited_deserialize(&maybe_ix.data), Ok(SystemInstruction::AdvanceNonceAccount))
-        )
+        .filter(|instruction| {
+            // Is system program
+            matches!(
+                message.account_keys.get(instruction.program_id_index as usize),
+                Some(program_id) if system_program::check_id(program_id)
+            )
+            // Is a nonce advance instruction
+            && matches!(
+                limited_deserialize(&instruction.data),
+                Ok(SystemInstruction::AdvanceNonceAccount)
+            )
+            // Nonce account is writable
+            && matches!(
+                instruction.accounts.get(0),
+                Some(index) if message.is_writable(*index as usize, true)
+            )
+        })
 }
 
 #[deprecated]
@@ -532,7 +541,7 @@ mod tests {
         hash::hash,
         instruction::AccountMeta,
         signature::{Keypair, Presigner, Signer},
-        system_instruction,
+        system_instruction, sysvar,
     };
     use bincode::{deserialize, serialize, serialized_size};
     use std::mem::size_of;
@@ -993,6 +1002,32 @@ mod tests {
         assert!(uses_durable_nonce(&tx).is_none());
     }
 
+    #[test]
+    fn tx_uses_ro_nonce_account() {
+        let from_keypair = Keypair::new();
+        let from_pubkey = from_keypair.pubkey();
+        let nonce_keypair = Keypair::new();
+        let nonce_pubkey = nonce_keypair.pubkey();
+        let account_metas = vec![
+            AccountMeta::new_readonly(nonce_pubkey, false),
+            #[allow(deprecated)]
+            AccountMeta::new_readonly(sysvar::recent_blockhashes::id(), false),
+            AccountMeta::new_readonly(nonce_pubkey, true),
+        ];
+        let nonce_instruction = Instruction::new_with_bincode(
+            system_program::id(),
+            &system_instruction::SystemInstruction::AdvanceNonceAccount,
+            account_metas,
+        );
+        let tx = Transaction::new_signed_with_payer(
+            &[nonce_instruction],
+            Some(&from_pubkey),
+            &[&from_keypair, &nonce_keypair],
+            Hash::default(),
+        );
+        assert!(uses_durable_nonce(&tx).is_none());
+    }
+
     #[test]
     fn tx_uses_nonce_wrong_first_nonce_ix_fail() {
         let from_keypair = Keypair::new();

sdk/src/transaction/sanitized.rs

@@ -161,7 +161,7 @@ impl SanitizedTransaction {
     }
 
     /// If the transaction uses a durable nonce, return the pubkey of the nonce account
-    pub fn get_durable_nonce(&self) -> Option<&Pubkey> {
+    pub fn get_durable_nonce(&self, nonce_must_be_writable: bool) -> Option<&Pubkey> {
         self.message
             .instructions()
             .get(NONCED_TX_MARKER_IX_INDEX as usize)
@@ -180,7 +180,11 @@ impl SanitizedTransaction {
             .and_then(|ix| {
                 ix.accounts.get(0).and_then(|idx| {
                     let idx = *idx as usize;
-                    self.message.get_account_key(idx)
+                    if nonce_must_be_writable && !self.message.is_writable(idx, true) {
+                        None
+                    } else {
+                        self.message.get_account_key(idx)
+                    }
                 })
             })
     }