From a56b2534d59fcd008ff2bdce4917244dedf3b88a Mon Sep 17 00:00:00 2001
From: Roman Zeyde <roman.zeyde@satoshilabs.com>
Date: Thu, 17 Jul 2025 23:09:35 +0300
Subject: [PATCH] fix(core): don't fail in case Solana rent cannot be
 calculated

---
 core/.changelog.d/5369.fixed                 |  1 +
 core/src/apps/solana/transaction/__init__.py | 19 +++++++++++++------
 2 files changed, 14 insertions(+), 6 deletions(-)
 create mode 100644 core/.changelog.d/5369.fixed

diff --git a/core/.changelog.d/5369.fixed b/core/.changelog.d/5369.fixed
new file mode 100644
index 0000000000..218ecbe0bd
--- /dev/null
+++ b/core/.changelog.d/5369.fixed
@@ -0,0 +1 @@
+Fixed Solana signature failure.
diff --git a/core/src/apps/solana/transaction/__init__.py b/core/src/apps/solana/transaction/__init__.py
index bb2421bf74..989ccfa206 100644
--- a/core/src/apps/solana/transaction/__init__.py
+++ b/core/src/apps/solana/transaction/__init__.py
@@ -222,7 +222,7 @@ class Transaction:
             if not instruction.is_ui_hidden
         ]
 
-    def calculate_fee(self) -> Fee:
+    def calculate_fee(self) -> Fee | None:
         number_of_signers = 0
         for address in self.addresses:
             if address[1] == AddressType.AddressSig:
@@ -253,21 +253,26 @@ class Transaction:
                     is_unit_price_set = True
 
         priority_fee = unit_price * unit_limit  # in microlamports
+        rent = self.calculate_rent()
+        if rent is None:
+            return None
         return Fee(
             base=base_fee,
             priority=(priority_fee + MICROLAMPORTS_PER_LAMPORT - 1)
             // MICROLAMPORTS_PER_LAMPORT,
-            rent=self.calculate_rent(),
+            rent=rent,
         )
 
-    def get_account_address(self, account: Account) -> bytes:
+    def get_account_address(self, account: Account) -> bytes | None:
         if len(account) == 2:
             return account[0]
         else:
-            _, index, _ = account
-            return self.addresses[index][0]
+            # AddressReference points to an Address Lookup Table account, whose contents are unavailable here:
+            # https://github.com/trezor/trezor-firmware/issues/5369#issuecomment-3083683085
+            # https://docs.anza.xyz/proposals/versioned-transactions#limitations
+            return None
 
-    def calculate_rent(self) -> int:
+    def calculate_rent(self) -> int | None:
         """
         Returns max rent exemption in lamports.
 
@@ -321,6 +326,8 @@ class Transaction:
                     allocation += (
                         SOLANA_TOKEN22_MAX_ACCOUNT_SIZE + SOLANA_ACCOUNT_OVERHEAD_SIZE
                     )
+                else:
+                    return None
 
         rent_exemption = (
             allocation