oss/luanti
oss/luanti
1
0
Fork 0
mirror of https://github.com/luanti-org/luanti.git synced 2025-06-27 16:36:03 +00:00
Code Wiki Activity

Prevent VoxelManipulator size overflow

Browse source
This commit is contained in:
sfan5 2025-01-08 19:30:48 +01:00
parent 2cdf3af1b8
commit 9dd09d1056
4 changed files with 33 additions and 31 deletions
Download patch file Download diff file Expand all files Collapse all files

30
src/voxel.cpp
View file

@ -113,6 +113,20 @@ void VoxelManipulator::print(std::ostream &o, const NodeDefManager *ndef,
}
}
static inline void checkArea(const VoxelArea &a)
{
// won't overflow since cbrt(2^64) > 2^16
u64 real_volume = static_cast<u64>(a.getExtent().X) * a.getExtent().Y * a.getExtent().Z;
// Volume limit equal to 8 default mapchunks, (80 * 2) ^ 3 = 4,096,000
// Note: the hard limit is somewhere around 2^31 due to s32 type
constexpr u64 MAX_ALLOWED = 4096000;
if (real_volume > MAX_ALLOWED) {
throw BaseException("VoxelManipulator: "
"Area volume exceeds allowed value of " + std::to_string(MAX_ALLOWED));
}
}
void VoxelManipulator::addArea(const VoxelArea &area)
{
// Cancel if requested area has zero volume
@ -124,18 +138,10 @@ void VoxelManipulator::addArea(const VoxelArea &area)
return;
// Calculate new area
VoxelArea new_area;
// New area is the requested area if m_area has zero volume
if(m_area.hasEmptyExtent())
{
new_area = area;
}
// Else add requested area to m_area
else
{
new_area = m_area;
new_area.addArea(area);
}
VoxelArea new_area = m_area;
new_area.addArea(area);
checkArea(new_area);
u32 new_size = new_area.getVolume();