Fix StreamingMemoryObject to respect known object size.

The existing code for method StreamingMemoryObject.fetchToPos does not respect
the corresonding call to setKnownObjectSize(). As a result, it allows the
StreamingMemoryObject to read bytes past the object size.

This patch provides a test case, and code to fix the problem.

Patch by Karl Schimpf
Differential Revision: http://reviews.llvm.org/D8931

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237939 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Derek Schuff
2015-05-21 19:40:19 +00:00
parent ad7c1174c7
commit 493bc7e300
3 changed files with 33 additions and 16 deletions

View File

@@ -73,7 +73,7 @@ namespace llvm {
// block until we actually want to read it.
bool StreamingMemoryObject::isValidAddress(uint64_t address) const {
if (ObjectSize && address < ObjectSize) return true;
return fetchToPos(address);
return fetchToPos(address);
}
uint64_t StreamingMemoryObject::getExtent() const {
@@ -87,13 +87,18 @@ uint64_t StreamingMemoryObject::getExtent() const {
uint64_t StreamingMemoryObject::readBytes(uint8_t *Buf, uint64_t Size,
uint64_t Address) const {
fetchToPos(Address + Size - 1);
if (Address >= BytesRead)
// Note: For wrapped bitcode files will set ObjectSize after the
// first call to fetchToPos. In such cases, ObjectSize can be
// smaller than BytesRead.
size_t MaxAddress =
(ObjectSize && ObjectSize < BytesRead) ? ObjectSize : BytesRead;
if (Address >= MaxAddress)
return 0;
uint64_t End = Address + Size;
if (End > BytesRead)
End = BytesRead;
assert(static_cast<int64_t>(End - Address) >= 0);
if (End > MaxAddress)
End = MaxAddress;
assert(End >= Address);
Size = End - Address;
memcpy(Buf, &Bytes[Address + BytesSkipped], Size);
return Size;
@@ -109,6 +114,8 @@ bool StreamingMemoryObject::dropLeadingBytes(size_t s) {
void StreamingMemoryObject::setKnownObjectSize(size_t size) {
ObjectSize = size;
Bytes.reserve(size);
if (ObjectSize <= BytesRead)
EOFReached = true;
}
MemoryObject *getNonStreamedMemoryObject(const unsigned char *Start,