Add error checking for Mach-O universal files.
Add the checking for both the MachO::fat_header and the
MachO::fat_arch struct values in the constructor for
MachOUniversalBinary. Such that when the constructor
for ObjectForArch is called it can assume the values in
the MachO::fat_arch for the offset and size are contained
in the file after the MachOUniversalBinary constructor
is called for the Parent.
llvm-svn: 288084
diff --git a/llvm/lib/Object/MachOUniversal.cpp b/llvm/lib/Object/MachOUniversal.cpp
index 9ab0ae6..7ddc427 100644
--- a/llvm/lib/Object/MachOUniversal.cpp
+++ b/llvm/lib/Object/MachOUniversal.cpp
@@ -42,6 +42,7 @@
MachOUniversalBinary::ObjectForArch::ObjectForArch(
const MachOUniversalBinary *Parent, uint32_t Index)
: Parent(Parent), Index(Index) {
+ // The iterators use Parent as a nullptr and an Index+1 == NumberOfObjects.
if (!Parent || Index >= Parent->getNumberOfObjects()) {
clear();
} else {
@@ -51,16 +52,10 @@
const char *HeaderPos = ParentData.begin() + sizeof(MachO::fat_header) +
Index * sizeof(MachO::fat_arch);
Header = getUniversalBinaryStruct<MachO::fat_arch>(HeaderPos);
- if (ParentData.size() < Header.offset + Header.size) {
- clear();
- }
} else { // Parent->getMagic() == MachO::FAT_MAGIC_64
const char *HeaderPos = ParentData.begin() + sizeof(MachO::fat_header) +
Index * sizeof(MachO::fat_arch_64);
Header64 = getUniversalBinaryStruct<MachO::fat_arch_64>(HeaderPos);
- if (ParentData.size() < Header64.offset + Header64.size) {
- clear();
- }
}
}
}
@@ -131,6 +126,10 @@
getUniversalBinaryStruct<MachO::fat_header>(Buf.begin());
Magic = H.magic;
NumberOfObjects = H.nfat_arch;
+ if (NumberOfObjects == 0) {
+ Err = malformedError("contains zero architecture types");
+ return;
+ }
uint32_t MinSize = sizeof(MachO::fat_header);
if (Magic == MachO::FAT_MAGIC)
MinSize += sizeof(MachO::fat_arch) * NumberOfObjects;
@@ -146,6 +145,68 @@
" structs would extend past the end of the file");
return;
}
+ for (uint32_t i = 0; i < NumberOfObjects; i++) {
+ ObjectForArch A(this, i);
+ uint64_t bigSize = A.getOffset();
+ bigSize += A.getSize();
+ if (bigSize > Buf.size()) {
+ Err = malformedError("offset plus size of cputype (" +
+ Twine(A.getCPUType()) + ") cpusubtype (" +
+ Twine(A.getCPUSubType() & ~MachO::CPU_SUBTYPE_MASK) +
+ ") extends past the end of the file");
+ return;
+ }
+#define MAXSECTALIGN 15 /* 2**15 or 0x8000 */
+ if (A.getAlign() > MAXSECTALIGN) {
+ Err = malformedError("align (2^" + Twine(A.getAlign()) + ") too large "
+ "for cputype (" + Twine(A.getCPUType()) + ") cpusubtype (" +
+ Twine(A.getCPUSubType() & ~MachO::CPU_SUBTYPE_MASK) +
+ ") (maximum 2^" + Twine(MAXSECTALIGN) + ")");
+ return;
+ }
+ if(A.getOffset() % (1 << A.getAlign()) != 0){
+ Err = malformedError("offset: " + Twine(A.getOffset()) +
+ " for cputype (" + Twine(A.getCPUType()) + ") cpusubtype (" +
+ Twine(A.getCPUSubType() & ~MachO::CPU_SUBTYPE_MASK) +
+ ") not aligned on it's alignment (2^" + Twine(A.getAlign()) + ")");
+ return;
+ }
+ if (A.getOffset() < MinSize) {
+ Err = malformedError("cputype (" + Twine(A.getCPUType()) + ") "
+ "cpusubtype (" + Twine(A.getCPUSubType() & ~MachO::CPU_SUBTYPE_MASK) +
+ ") offset " + Twine(A.getOffset()) + " overlaps universal headers");
+ return;
+ }
+ }
+ for (uint32_t i = 0; i < NumberOfObjects; i++) {
+ ObjectForArch A(this, i);
+ for (uint32_t j = i + 1; j < NumberOfObjects; j++) {
+ ObjectForArch B(this, j);
+ if (A.getCPUType() == B.getCPUType() &&
+ (A.getCPUSubType() & ~MachO::CPU_SUBTYPE_MASK) ==
+ (B.getCPUSubType() & ~MachO::CPU_SUBTYPE_MASK)) {
+ Err = malformedError("contains two of the same architecture (cputype "
+ "(" + Twine(A.getCPUType()) + ") cpusubtype (" +
+ Twine(A.getCPUSubType() & ~MachO::CPU_SUBTYPE_MASK) + "))");
+ return;
+ }
+ if ((A.getOffset() >= B.getOffset() &&
+ A.getOffset() < B.getOffset() + B.getSize()) ||
+ (A.getOffset() + A.getSize() > B.getOffset() &&
+ A.getOffset() + A.getSize() < B.getOffset() + B.getSize()) ||
+ (A.getOffset() <= B.getOffset() &&
+ A.getOffset() + A.getSize() >= B.getOffset() + B.getSize())) {
+ Err = malformedError("cputype (" + Twine(A.getCPUType()) + ") "
+ "cpusubtype (" + Twine(A.getCPUSubType() & ~MachO::CPU_SUBTYPE_MASK) +
+ ") at offset " + Twine(A.getOffset()) + " with a size of " +
+ Twine(A.getSize()) + ", overlaps cputype (" + Twine(B.getCPUType()) +
+ ") cpusubtype (" + Twine(B.getCPUSubType() & ~MachO::CPU_SUBTYPE_MASK)
+ + ") at offset " + Twine(B.getOffset()) + " with a size of "
+ + Twine(B.getSize()));
+ return;
+ }
+ }
+ }
Err = Error::success();
}