From 132804811d141d29bef341fa5d30dd4b934beeb5 Mon Sep 17 00:00:00 2001 From: Crypto City Date: Tue, 21 Mar 2023 09:02:38 +0000 Subject: [PATCH] wallet2: fix infinite loop in fake out selection The gamma picker and the caller code did not quite agree on the number of rct outputs available for use - by one block - which caused an infinite loop if the picker could never pick outputs from that block but already had picked all other outputs from previous blocks. Also change the range to select from using code from UkoeHB. --- src/wallet/wallet2.cpp | 6 +++--- src/wallet/wallet2.h | 1 + 2 files changed, 4 insertions(+), 3 deletions(-) diff --git a/src/wallet/wallet2.cpp b/src/wallet/wallet2.cpp index 91de4fe09..63e87e52e 100644 --- a/src/wallet/wallet2.cpp +++ b/src/wallet/wallet2.cpp @@ -1005,7 +1005,7 @@ gamma_picker::gamma_picker(const std::vector &rct_offsets, double shap const size_t blocks_to_consider = std::min(rct_offsets.size(), blocks_in_a_year); const size_t outputs_to_consider = rct_offsets.back() - (blocks_to_consider < rct_offsets.size() ? rct_offsets[rct_offsets.size() - blocks_to_consider - 1] : 0); begin = rct_offsets.data(); - end = rct_offsets.data() + rct_offsets.size() - CRYPTONOTE_DEFAULT_TX_SPENDABLE_AGE; + end = rct_offsets.data() + rct_offsets.size() - (std::max(1, CRYPTONOTE_DEFAULT_TX_SPENDABLE_AGE) - 1); num_rct_outputs = *(end - 1); THROW_WALLET_EXCEPTION_IF(num_rct_outputs == 0, error::wallet_internal_error, "No rct outputs"); average_output_time = DIFFICULTY_TARGET_V2 * blocks_to_consider / static_cast(outputs_to_consider); // this assumes constant target over the whole rct range @@ -8408,7 +8408,7 @@ void wallet2::get_outs(std::vector> else { // the base offset of the first rct output in the first unlocked block (or the one to be if there's none) - num_outs = rct_offsets[rct_offsets.size() - CRYPTONOTE_DEFAULT_TX_SPENDABLE_AGE]; + num_outs = gamma->get_num_rct_outs(); LOG_PRINT_L1("" << num_outs << " unlocked rct outputs"); THROW_WALLET_EXCEPTION_IF(num_outs == 0, error::wallet_internal_error, "histogram reports no unlocked rct outputs, not even ours"); @@ -8692,7 +8692,7 @@ void wallet2::get_outs(std::vector> } bool use_histogram = amount != 0; if (!use_histogram) - num_outs = rct_offsets[rct_offsets.size() - CRYPTONOTE_DEFAULT_TX_SPENDABLE_AGE]; + num_outs = gamma->get_num_rct_outs(); // make sure the real outputs we asked for are really included, along // with the correct key and mask: this guards against an active attack diff --git a/src/wallet/wallet2.h b/src/wallet/wallet2.h index 3fcefd16f..50975c756 100644 --- a/src/wallet/wallet2.h +++ b/src/wallet/wallet2.h @@ -101,6 +101,7 @@ namespace tools uint64_t pick(); gamma_picker(const std::vector &rct_offsets); gamma_picker(const std::vector &rct_offsets, double shape, double scale); + uint64_t get_num_rct_outs() const { return num_rct_outputs; } private: struct gamma_engine