From 8bbcb05303cb6beb9c1013fd5d7e85a364e02ae8 Mon Sep 17 00:00:00 2001 From: Connor McLaughlin Date: Tue, 24 May 2022 18:05:04 +1000 Subject: [PATCH] MultipartFileReader: Fix use-after-free when opening multipart files Also fixes loading uppercase filenames on Linux. --- pcsx2/CDVD/InputIsoFile.cpp | 3 --- pcsx2/MultipartFileReader.cpp | 16 +++++++++++++--- 2 files changed, 13 insertions(+), 6 deletions(-) diff --git a/pcsx2/CDVD/InputIsoFile.cpp b/pcsx2/CDVD/InputIsoFile.cpp index 4ebaf1dd9f..c9910fd80d 100644 --- a/pcsx2/CDVD/InputIsoFile.cpp +++ b/pcsx2/CDVD/InputIsoFile.cpp @@ -262,10 +262,7 @@ bool InputIsoFile::Open(std::string srcfile, bool testOnly) m_reader->SetBlockSize(m_blocksize); // Returns the original reader if single-part or a Multipart reader otherwise - AsyncFileReader* m_reader_old = m_reader; m_reader = MultipartFileReader::DetectMultipart(m_reader); - if (m_reader != m_reader_old) // Not the same object the old one need to be deleted - delete m_reader_old; } m_blocks = m_reader->GetBlockCount(); diff --git a/pcsx2/MultipartFileReader.cpp b/pcsx2/MultipartFileReader.cpp index 480279d232..14d1bcdc56 100644 --- a/pcsx2/MultipartFileReader.cpp +++ b/pcsx2/MultipartFileReader.cpp @@ -22,7 +22,7 @@ // Tests for a filename extension in both upper and lower case, if the filesystem happens // to be case-sensitive. -static bool pxFileExists_WithExt( const std::string& filename, const std::string& ext ) +static bool pxFileExists_WithExt( std::string& filename, const std::string& ext ) { std::string temp(Path::ReplaceExtension(filename, StringUtil::toLower(ext))); if (FileSystem::FileExists(temp.c_str())) @@ -31,7 +31,11 @@ static bool pxFileExists_WithExt( const std::string& filename, const std::string #if defined(_WIN32) || defined(__DARWIN__) temp = Path::ReplaceExtension(filename, StringUtil::toUpper(ext)); if (FileSystem::FileExists(temp.c_str())) + { + // make sure we open the correct one + filename = std::move(temp); return true; + } #endif return false; @@ -114,11 +118,17 @@ void MultipartFileReader::FindParts() break; Part* thispart = m_parts + m_numparts; - AsyncFileReader* thisreader = thispart->reader = new FlatFileReader(); + AsyncFileReader* thisreader = new FlatFileReader(); + + if (!thisreader->Open(nameparts)) + { + delete thisreader; + break; + } - thisreader->Open(nameparts); thisreader->SetBlockSize(bsize); + thispart->reader = thisreader; thispart->start = blocks; uint bcount = thisreader->GetBlockCount();