diff options
Diffstat (limited to 'core/src/fxcrt/fx_basic_wstring.cpp')
| -rw-r--r-- | core/src/fxcrt/fx_basic_wstring.cpp | 35 |
1 files changed, 24 insertions, 11 deletions
diff --git a/core/src/fxcrt/fx_basic_wstring.cpp b/core/src/fxcrt/fx_basic_wstring.cpp index 7af3303ca2..68a65d5b6b 100644 --- a/core/src/fxcrt/fx_basic_wstring.cpp +++ b/core/src/fxcrt/fx_basic_wstring.cpp @@ -5,15 +5,26 @@ // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com #include "../../include/fxcrt/fx_basic.h" +#include "../../../third_party/numerics/safe_math.h" + static CFX_StringDataW* FX_AllocStringW(int nLen) { - if (nLen == 0) { + if (nLen == 0 || nLen < 0) { return NULL; } - CFX_StringDataW* pData = (CFX_StringDataW*)FX_Alloc(FX_BYTE, sizeof(long) * 3 + (nLen + 1) * sizeof(FX_WCHAR)); + + base::CheckedNumeric<int> iSize = static_cast<int>(sizeof(FX_WCHAR)); + iSize *= nLen + 1; + iSize += sizeof(long) * 3; + CFX_StringDataW* pData = (CFX_StringDataW*)FX_Alloc(FX_BYTE, iSize.ValueOrDie()); if (!pData) { return NULL; } + + // TODO(palmer): |nLen| should really be declared as |size_t|, but for + // now I just want to fix the overflow without changing any interfaces. + // Declaring |nLen| as |size_t| will also simplify the above code + // somewhat. pData->m_nAllocLength = nLen; pData->m_nDataLength = nLen; pData->m_nRefs = 1; @@ -421,17 +432,19 @@ CFX_WideString CFX_WideString::FromUTF16LE(const unsigned short* wstr, FX_STRSIZ result.ReleaseBuffer(wlen); return result; } -void CFX_WideString::AllocCopy(CFX_WideString& dest, FX_STRSIZE nCopyLen, FX_STRSIZE nCopyIndex, - FX_STRSIZE nExtraLen) const +void CFX_WideString::AllocCopy(CFX_WideString& dest, FX_STRSIZE nCopyLen, FX_STRSIZE nCopyIndex) const { - FX_STRSIZE nNewLen = nCopyLen + nExtraLen; - if (nNewLen == 0) { + // |FX_STRSIZE| is currently typedef'd as in |int|. TODO(palmer): It + // should be a |size_t|, or at least unsigned. + if (nCopyLen == 0 || nCopyLen < 0) { return; } + base::CheckedNumeric<FX_STRSIZE> iSize = static_cast<FX_STRSIZE>(sizeof(FX_WCHAR)); + iSize *= nCopyLen; ASSERT(dest.m_pData == NULL); - dest.m_pData = FX_AllocStringW(nNewLen); + dest.m_pData = FX_AllocStringW(nCopyLen); if (dest.m_pData) { - FXSYS_memcpy32(dest.m_pData->m_String, m_pData->m_String + nCopyIndex, nCopyLen * sizeof(FX_WCHAR)); + FXSYS_memcpy32(dest.m_pData->m_String, m_pData->m_String + nCopyIndex, iSize.ValueOrDie()); } } CFX_WideString CFX_WideString::Left(FX_STRSIZE nCount) const @@ -446,7 +459,7 @@ CFX_WideString CFX_WideString::Left(FX_STRSIZE nCount) const return *this; } CFX_WideString dest; - AllocCopy(dest, nCount, 0, 0); + AllocCopy(dest, nCount, 0); return dest; } CFX_WideString CFX_WideString::Mid(FX_STRSIZE nFirst) const @@ -474,7 +487,7 @@ CFX_WideString CFX_WideString::Mid(FX_STRSIZE nFirst, FX_STRSIZE nCount) const return *this; } CFX_WideString dest; - AllocCopy(dest, nCount, nFirst, 0); + AllocCopy(dest, nCount, nFirst); return dest; } CFX_WideString CFX_WideString::Right(FX_STRSIZE nCount) const @@ -489,7 +502,7 @@ CFX_WideString CFX_WideString::Right(FX_STRSIZE nCount) const return *this; } CFX_WideString dest; - AllocCopy(dest, nCount, m_pData->m_nDataLength - nCount, 0); + AllocCopy(dest, nCount, m_pData->m_nDataLength - nCount); return dest; } int CFX_WideString::CompareNoCase(FX_LPCWSTR lpsz) const |