wallet: fix scanning progress calculation for single block range

If the blockchain is rescanned for a single block (i.e. start and stop hashes are equal, and with that also the estimated verification progress) the progress calculation could lead to a NaN value caused by a division by zero, resulting in an invalid JSON result for the getwalletinfo RPC. Fixed by setting the progress to zero in that special case. Co-authored-by: MarcoFalke <[email protected]>
knst · Nov 11, 2020 · 5e14602 · 5e14602
1 parent 7e37329
commit 5e14602
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Showing 2 changed files with 5 additions and 2 deletions.
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
@@ -1778,7 +1778,11 @@ CWallet::ScanResult CWallet::ScanForWalletTransactions(const uint256& start_bloc
     double progress_current = progress_begin;
     int block_height = start_height;
     while (!fAbortRescan && !chain().shutdownRequested()) {
-        m_scanning_progress = (progress_current - progress_begin) / (progress_end - progress_begin);
+        if (progress_end - progress_begin > 0.0) {
+            m_scanning_progress = (progress_current - progress_begin) / (progress_end - progress_begin);
+        } else { // avoid divide-by-zero for single block scan range (i.e. start and stop hashes are equal)
+            m_scanning_progress = 0;
+        }
         if (block_height % 100 == 0 && progress_end - progress_begin > 0.0) {
             ShowProgress(strprintf("%s " + _("Rescanning...").translated, GetDisplayName()), std::max(1, std::min(99, (int)(m_scanning_progress * 100))));
         }

diff --git a/test/sanitizer_suppressions/ubsan b/test/sanitizer_suppressions/ubsan
@@ -1,7 +1,6 @@
 # -fsanitize=undefined suppressions
 # =================================
 float-divide-by-zero:validation.cpp
-float-divide-by-zero:wallet/wallet.cpp
 
 # -fsanitize=integer suppressions
 # ===============================