diff options
6 files changed, 205 insertions, 18 deletions
diff --git a/lld/lib/ReaderWriter/MachO/MachONormalizedFile.h b/lld/lib/ReaderWriter/MachO/MachONormalizedFile.h index 6dab8babe65..e01d72cc94d 100644 --- a/lld/lib/ReaderWriter/MachO/MachONormalizedFile.h +++ b/lld/lib/ReaderWriter/MachO/MachONormalizedFile.h @@ -172,7 +172,8 @@ struct Segment { StringRef name; Hex64 address; Hex64 size; - VMProtect access; + VMProtect init_access; + VMProtect max_access; }; /// Only used in normalized final linked images to specify on which dylibs diff --git a/lld/lib/ReaderWriter/MachO/MachONormalizedFileBinaryWriter.cpp b/lld/lib/ReaderWriter/MachO/MachONormalizedFileBinaryWriter.cpp index 8a11a5c7bac..b57afc0180e 100644 --- a/lld/lib/ReaderWriter/MachO/MachONormalizedFileBinaryWriter.cpp +++ b/lld/lib/ReaderWriter/MachO/MachONormalizedFileBinaryWriter.cpp @@ -570,7 +570,7 @@ void MachOFileLayout::buildFileOffsets() { llvm::dbgs() << "buildFileOffsets()\n"); for (const Segment &sg : _file.segments) { _segInfo[&sg].fileOffset = fileOffset; - if ((_seg1addr == INT64_MAX) && sg.access) + if ((_seg1addr == INT64_MAX) && sg.init_access) _seg1addr = sg.address; DEBUG_WITH_TYPE("MachOFileLayout", llvm::dbgs() << " segment=" << sg.name @@ -578,7 +578,7 @@ void MachOFileLayout::buildFileOffsets() { uint32_t segFileSize = 0; // A segment that is not zero-fill must use a least one page of disk space. - if (sg.access) + if (sg.init_access) segFileSize = _file.pageSize; for (const Section *s : _segInfo[&sg].sections) { uint32_t sectOffset = s->address - sg.address; @@ -711,8 +711,8 @@ std::error_code MachOFileLayout::writeSegmentLoadCommands(uint8_t *&lc) { cmd->vmsize = llvm::alignTo(linkeditSize, _file.pageSize); cmd->fileoff = _startOfLinkEdit; cmd->filesize = linkeditSize; - cmd->initprot = seg.access; - cmd->maxprot = seg.access; + cmd->initprot = seg.init_access; + cmd->maxprot = seg.max_access; cmd->nsects = 0; cmd->flags = 0; if (_swap) @@ -731,8 +731,8 @@ std::error_code MachOFileLayout::writeSegmentLoadCommands(uint8_t *&lc) { cmd->vmsize = seg.size; cmd->fileoff = segInfo.fileOffset; cmd->filesize = segInfo.fileSize; - cmd->maxprot = seg.access; - cmd->initprot = seg.access; + cmd->initprot = seg.init_access; + cmd->maxprot = seg.max_access; cmd->nsects = segInfo.sections.size(); cmd->flags = 0; if (_swap) diff --git a/lld/lib/ReaderWriter/MachO/MachONormalizedFileFromAtoms.cpp b/lld/lib/ReaderWriter/MachO/MachONormalizedFileFromAtoms.cpp index 684c535a913..73f4e146906 100644 --- a/lld/lib/ReaderWriter/MachO/MachONormalizedFileFromAtoms.cpp +++ b/lld/lib/ReaderWriter/MachO/MachONormalizedFileFromAtoms.cpp @@ -92,13 +92,15 @@ struct SegmentInfo { StringRef name; uint64_t address; uint64_t size; - uint32_t access; + uint32_t init_access; + uint32_t max_access; std::vector<SectionInfo*> sections; uint32_t normalizedSegmentIndex; }; SegmentInfo::SegmentInfo(StringRef n) - : name(n), address(0), size(0), access(0), normalizedSegmentIndex(0) { + : name(n), address(0), size(0), init_access(0), max_access(0), + normalizedSegmentIndex(0) { } class Util { @@ -432,12 +434,38 @@ SegmentInfo *Util::segmentForName(StringRef segName) { return si; } auto *info = new (_allocator) SegmentInfo(segName); + + // Set the initial segment protection. if (segName.equals("__TEXT")) - info->access = VM_PROT_READ | VM_PROT_EXECUTE; - else if (segName.equals("__DATA")) - info->access = VM_PROT_READ | VM_PROT_WRITE; + info->init_access = VM_PROT_READ | VM_PROT_EXECUTE; else if (segName.equals("__PAGEZERO")) - info->access = 0; + info->init_access = 0; + else if (segName.equals("__LINKEDIT")) + info->init_access = VM_PROT_READ; + else { + // All others default to read-write + info->init_access = VM_PROT_READ | VM_PROT_WRITE; + } + + // Set max segment protection + // Note, its overkill to use a switch statement here, but makes it so much + // easier to use switch coverage to catch new cases. + switch (_ctx.os()) { + case lld::MachOLinkingContext::OS::unknown: + case lld::MachOLinkingContext::OS::macOSX: + case lld::MachOLinkingContext::OS::iOS_simulator: + if (segName.equals("__PAGEZERO")) { + info->max_access = 0; + break; + } + // All others default to all + info->max_access = VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE; + break; + case lld::MachOLinkingContext::OS::iOS: + // iPhoneOS always uses same protection for max and initial + info->max_access = info->init_access; + break; + } _segmentInfos.push_back(info); return info; } @@ -589,7 +617,8 @@ void Util::copySegmentInfo(NormalizedFile &file) { seg.name = sgi->name; seg.address = sgi->address; seg.size = sgi->size; - seg.access = sgi->access; + seg.init_access = sgi->init_access; + seg.max_access = sgi->max_access; file.segments.push_back(seg); } } diff --git a/lld/lib/ReaderWriter/MachO/MachONormalizedFileYAML.cpp b/lld/lib/ReaderWriter/MachO/MachONormalizedFileYAML.cpp index c795a72530a..5ae9204f72b 100644 --- a/lld/lib/ReaderWriter/MachO/MachONormalizedFileYAML.cpp +++ b/lld/lib/ReaderWriter/MachO/MachONormalizedFileYAML.cpp @@ -504,10 +504,11 @@ struct ScalarTraits<VMProtect> { template <> struct MappingTraits<Segment> { static void mapping(IO &io, Segment& seg) { - io.mapRequired("name", seg.name); - io.mapRequired("address", seg.address); - io.mapRequired("size", seg.size); - io.mapRequired("access", seg.access); + io.mapRequired("name", seg.name); + io.mapRequired("address", seg.address); + io.mapRequired("size", seg.size); + io.mapRequired("init-access", seg.init_access); + io.mapRequired("max-access", seg.max_access); } }; diff --git a/lld/test/mach-o/seg-protection-arm64.yaml b/lld/test/mach-o/seg-protection-arm64.yaml new file mode 100644 index 00000000000..f63b33ad2dc --- /dev/null +++ b/lld/test/mach-o/seg-protection-arm64.yaml @@ -0,0 +1,78 @@ +# RUN: lld -flavor darwin -arch arm64 %s %p/Inputs/hello-world-arm64.yaml -o %t && llvm-objdump -private-headers %t | FileCheck %s + +--- !mach-o +arch: arm64 +file-type: MH_OBJECT +flags: [ MH_SUBSECTIONS_VIA_SYMBOLS ] +has-UUID: false +OS: unknown +sections: + - segment: __TEXT + section: __text + type: S_REGULAR + attributes: [ S_ATTR_PURE_INSTRUCTIONS, S_ATTR_SOME_INSTRUCTIONS ] + address: 0x0000000000000000 + content: [ 0x00, 0x00 ] +global-symbols: + - name: _main + type: N_SECT + scope: [ N_EXT ] + sect: 1 + value: 0x0000000000000000 + - name: start + type: N_SECT + scope: [ N_EXT ] + sect: 1 + value: 0x0000000000000001 + +... + +# CHECK: Load command 0 +# CHECK: cmd LC_SEGMENT_64 +# CHECK: cmdsize 72 +# CHECK: segname __PAGEZERO +# CHECK: vmaddr +# CHECK: vmsize +# CHECK: fileoff +# CHECK: filesize +# CHECK: maxprot --- +# CHECK: initprot --- +# CHECK: nsects 0 +# CHECK: flags (none) +# CHECK: Load command 1 +# CHECK: cmd LC_SEGMENT_64 +# CHECK: cmdsize 152 +# CHECK: segname __TEXT +# CHECK: vmaddr +# CHECK: vmsize +# CHECK: fileoff +# CHECK: filesize +# CHECK: maxprot r-x +# CHECK: initprot r-x +# CHECK: nsects 1 +# CHECK: flags (none) +# CHECK: Section +# CHECK: sectname __text +# CHECK: segname __TEXT +# CHECK: addr +# CHECK: size +# CHECK: offset +# CHECK: align 2^0 (1) +# CHECK: reloff 0 +# CHECK: nreloc 0 +# CHECK: type S_REGULAR +# CHECK: attributes PURE_INSTRUCTIONS SOME_INSTRUCTIONS +# CHECK: reserved1 0 +# CHECK: reserved2 0 +# CHECK: Load command 2 +# CHECK: cmd LC_SEGMENT_64 +# CHECK: cmdsize 72 +# CHECK: segname __LINKEDIT +# CHECK: vmaddr +# CHECK: vmsize +# CHECK: fileoff +# CHECK: filesize +# CHECK: maxprot r-- +# CHECK: initprot r-- +# CHECK: nsects 0 +# CHECK: flags (none) diff --git a/lld/test/mach-o/seg-protection-x86_64.yaml b/lld/test/mach-o/seg-protection-x86_64.yaml new file mode 100644 index 00000000000..474f72f4c57 --- /dev/null +++ b/lld/test/mach-o/seg-protection-x86_64.yaml @@ -0,0 +1,78 @@ +# RUN: lld -flavor darwin -arch x86_64 %s %p/Inputs/hello-world-x86_64.yaml -o %t && llvm-objdump -private-headers %t | FileCheck %s + +--- !mach-o +arch: x86_64 +file-type: MH_OBJECT +flags: [ MH_SUBSECTIONS_VIA_SYMBOLS ] +has-UUID: false +OS: unknown +sections: + - segment: __TEXT + section: __text + type: S_REGULAR + attributes: [ S_ATTR_PURE_INSTRUCTIONS, S_ATTR_SOME_INSTRUCTIONS ] + address: 0x0000000000000000 + content: [ 0x00, 0x00 ] +global-symbols: + - name: _main + type: N_SECT + scope: [ N_EXT ] + sect: 1 + value: 0x0000000000000000 + - name: start + type: N_SECT + scope: [ N_EXT ] + sect: 1 + value: 0x0000000000000001 + +... + +# CHECK: Load command 0 +# CHECK: cmd LC_SEGMENT_64 +# CHECK: cmdsize 72 +# CHECK: segname __PAGEZERO +# CHECK: vmaddr +# CHECK: vmsize +# CHECK: fileoff +# CHECK: filesize +# CHECK: maxprot --- +# CHECK: initprot --- +# CHECK: nsects 0 +# CHECK: flags (none) +# CHECK: Load command 1 +# CHECK: cmd LC_SEGMENT_64 +# CHECK: cmdsize 152 +# CHECK: segname __TEXT +# CHECK: vmaddr +# CHECK: vmsize +# CHECK: fileoff +# CHECK: filesize +# CHECK: maxprot rwx +# CHECK: initprot r-x +# CHECK: nsects 1 +# CHECK: flags (none) +# CHECK: Section +# CHECK: sectname __text +# CHECK: segname __TEXT +# CHECK: addr +# CHECK: size +# CHECK: offset +# CHECK: align 2^0 (1) +# CHECK: reloff 0 +# CHECK: nreloc 0 +# CHECK: type S_REGULAR +# CHECK: attributes PURE_INSTRUCTIONS SOME_INSTRUCTIONS +# CHECK: reserved1 0 +# CHECK: reserved2 0 +# CHECK: Load command 2 +# CHECK: cmd LC_SEGMENT_64 +# CHECK: cmdsize 72 +# CHECK: segname __LINKEDIT +# CHECK: vmaddr +# CHECK: vmsize +# CHECK: fileoff +# CHECK: filesize +# CHECK: maxprot rwx +# CHECK: initprot r-- +# CHECK: nsects 0 +# CHECK: flags (none) |
