From 62e826fa76172210572356eef9fa3cd3309baf56 Mon Sep 17 00:00:00 2001
From: Ava Chow <github@achow101.com>
Date: Tue, 25 Aug 2026 15:14:48 -0700
Subject: [PATCH] wallet: Update WalletDescriptor from another one instead of
 overwriting

If a descriptor is being reimported, we should only update the metadata
and cache from the other one, rather than overwriting the entire thing.
This avoids a potential issue where the on-disk record is overwritten
with a backwards incompatible string.
---
 src/wallet/scriptpubkeyman.cpp                    |  2 +-
 src/wallet/walletutil.cpp                         | 12 ++++++++++++
 src/wallet/walletutil.h                           |  2 ++
 test/functional/wallet_backwards_compatibility.py | 11 +++++++----
 4 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/src/wallet/scriptpubkeyman.cpp b/src/wallet/scriptpubkeyman.cpp
index a7d7bc68cad..481d23f7dd3 100644
--- a/src/wallet/scriptpubkeyman.cpp
+++ b/src/wallet/scriptpubkeyman.cpp
@@ -1634,7 +1634,7 @@ util::Result<void> DescriptorScriptPubKeyMan::UpdateWalletDescriptor(WalletDescr
     m_map_pubkeys.clear();
     m_map_script_pub_keys.clear();
     m_max_cached_index = -1;
-    m_wallet_descriptor = descriptor;
+    m_wallet_descriptor.UpdateFrom(descriptor);
 
     WalletBatch batch(m_storage.GetDatabase());
     UpdateWithSigningProvider(batch, provider);
diff --git a/src/wallet/walletutil.cpp b/src/wallet/walletutil.cpp
index 85249f63275..9b0c2378a08 100644
--- a/src/wallet/walletutil.cpp
+++ b/src/wallet/walletutil.cpp
@@ -85,4 +85,16 @@ WalletDescriptor GenerateWalletDescriptor(const CExtPubKey& master_key, const Ou
     return w_desc;
 }
 
+void WalletDescriptor::UpdateFrom(const WalletDescriptor& other)
+{
+    if (descriptor->ToCanonicalString() != other.descriptor->ToCanonicalString()) {
+        return;
+    }
+    range_start = other.range_start;
+    next_index = other.next_index;
+    range_end = other.range_end;
+    creation_time = other.creation_time;
+    cache = other.cache;
+}
+
 } // namespace wallet
diff --git a/src/wallet/walletutil.h b/src/wallet/walletutil.h
index a85a339a2da..6e50c283dd4 100644
--- a/src/wallet/walletutil.h
+++ b/src/wallet/walletutil.h
@@ -128,6 +128,8 @@ public:
       descriptor(descriptor),
       id(DescriptorID(*descriptor)),
       creation_time(creation_time) {}
+
+    void UpdateFrom(const WalletDescriptor& other);
 };
 
 WalletDescriptor GenerateWalletDescriptor(const CExtPubKey& master_key, const OutputType& output_type, bool internal);
diff --git a/test/functional/wallet_backwards_compatibility.py b/test/functional/wallet_backwards_compatibility.py
index 9ae87c019b8..a16ae07bd3e 100755
--- a/test/functional/wallet_backwards_compatibility.py
+++ b/test/functional/wallet_backwards_compatibility.py
@@ -328,9 +328,12 @@ class BackwardsCompatibilityTest(BitcoinTestFramework):
 
         node_master.createwallet(wallet_name="miniscript")
         wallet = node_master.get_wallet_rpc("miniscript")
-        miniscript_desc = descsum_create("wsh(or_b(pk([deadbeef/0h/1h/2h]tprv8ZgxMBicQKsPerQj6m35no46amfKQdjY7AhLnmatHYXs8S4MTgeZYkWAn4edSGwwL3vkSiiGqSZQrmy5D3P5gBoqgvYP2fCUpBwbKTMTAkL/3h/*),s:pk([beefdead/4h/5h]tpubD6NzVbkrYhZ4YU9vM1s53UhD75UyJatx8EMzMZ3VUjR2FciNfLLkAw6a4pWACChzobTseNqdWk4G7ZdBqRDLtLSACKykTScmqibb1ZrCvJu/6/7/*)))")
-        res = wallet.importdescriptors([{"desc": miniscript_desc, "timestamp":"now"}])
-        assert_equal(res[0]["success"], True)
+        miniscript_desc = "wsh(or_b(pk([deadbeef/0h/1h/2h]tprv8ZgxMBicQKsPerQj6m35no46amfKQdjY7AhLnmatHYXs8S4MTgeZYkWAn4edSGwwL3vkSiiGqSZQrmy5D3P5gBoqgvYP2fCUpBwbKTMTAkL/3h/*),s:pk([beefdead/4h/5h]tpubD6NzVbkrYhZ4YU9vM1s53UhD75UyJatx8EMzMZ3VUjR2FciNfLLkAw6a4pWACChzobTseNqdWk4G7ZdBqRDLtLSACKykTScmqibb1ZrCvJu/6/7/*)))"
+        miniscript_apos = miniscript_desc.replace("[beefdead/4h/5h]", "[beefdead/4'/5']")
+        assert miniscript_apos != miniscript_desc
+        for desc in [miniscript_desc, miniscript_apos]:
+            res = wallet.importdescriptors([{"desc": descsum_create(desc), "timestamp":"now"}])
+            assert_equal(res[0]["success"], True)
 
         # Unload wallets and copy to older nodes:
         node_master_wallets_dir = node_master.wallets_path
@@ -425,7 +428,7 @@ class BackwardsCompatibilityTest(BitcoinTestFramework):
             pubkey = addr_info["pubkey"]
 
             if self.major_version_at_least(node, 24):
-                res = wallet_prev.importdescriptors([{"desc": miniscript_desc, "timestamp":"now"}])
+                res = wallet_prev.importdescriptors([{"desc": descsum_create(miniscript_desc), "timestamp":"now"}])
                 assert_equal(res[0]["success"], True)
 
             # Make a backup of the wallet file