From 5400980e1ed426a339073ed4e1ee48863a682a61 Mon Sep 17 00:00:00 2001 From: Alexey Samsonov Date: Thu, 4 Jun 2015 20:08:52 +0000 Subject: [PATCH] [Object, MachO] Don't crash on invalid MachO segment load commands. Summary: Properly report the error in segment load commands from MachOObjectFile constructor instead of crashing the program. Adjust the test case accordingly. Test Plan: regression test suite Reviewers: rafael, filcab Subscribers: llvm-commits git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239081 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/llvm/Object/Error.h | 2 ++ lib/Object/Error.cpp | 4 ++++ lib/Object/MachOObjectFile.cpp | 26 +++++++++++++++----------- test/Object/macho-invalid.test | 4 ++-- 4 files changed, 23 insertions(+), 13 deletions(-) diff --git a/include/llvm/Object/Error.h b/include/llvm/Object/Error.h index 13a14aa09c7..fe4372d4d96 100644 --- a/include/llvm/Object/Error.h +++ b/include/llvm/Object/Error.h @@ -29,6 +29,8 @@ enum class object_error { unexpected_eof, bitcode_section_not_found, macho_small_load_command, + macho_load_segment_too_many_sections, + macho_load_segment_too_small, }; inline std::error_code make_error_code(object_error e) { diff --git a/lib/Object/Error.cpp b/lib/Object/Error.cpp index 1c8dad80b0a..5e4e237f4b0 100644 --- a/lib/Object/Error.cpp +++ b/lib/Object/Error.cpp @@ -46,6 +46,10 @@ std::string _object_error_category::message(int EV) const { return "Bitcode section not found in object file"; case object_error::macho_small_load_command: return "Mach-O load command with size < 8 bytes"; + case object_error::macho_load_segment_too_many_sections: + return "Mach-O segment load command contains too many sections"; + case object_error::macho_load_segment_too_small: + return "Mach-O segment load command size is too small"; } llvm_unreachable("An enumerator of object_error does not have a message " "defined."); diff --git a/lib/Object/MachOObjectFile.cpp b/lib/Object/MachOObjectFile.cpp index 3262c6c26ab..62514d2ec9a 100644 --- a/lib/Object/MachOObjectFile.cpp +++ b/lib/Object/MachOObjectFile.cpp @@ -66,17 +66,16 @@ static ErrorOr getStructOrErr(const MachOObjectFile *O, const char *P) { } template -static uint32_t getSegmentLoadCommandNumSections(const SegmentCmd &S, - uint32_t Cmdsize) { +static ErrorOr getSegmentLoadCommandNumSections(const SegmentCmd &S, + uint32_t Cmdsize) { const unsigned SectionSize = sizeof(SegmentCmd); if (S.nsects > std::numeric_limits::max() / SectionSize || S.nsects * SectionSize > Cmdsize - sizeof(S)) - report_fatal_error( - "Number of sections too large for size of load command."); + return object_error::macho_load_segment_too_many_sections; return S.nsects; } -static uint32_t +static ErrorOr getSegmentLoadCommandNumSections(const MachOObjectFile *O, const MachOObjectFile::LoadCommandInfo &L) { if (O->is64Bit()) @@ -306,14 +305,19 @@ MachOObjectFile::MachOObjectFile(MemoryBufferRef Object, bool IsLittleEndian, } UuidLoadCmd = Load.Ptr; } else if (Load.C.cmd == SegmentLoadType) { - const unsigned SegmentLoadSize = this->is64Bit() + const unsigned SegmentLoadSize = is64Bit() ? sizeof(MachO::segment_command_64) : sizeof(MachO::segment_command); - if (Load.C.cmdsize < SegmentLoadSize) - report_fatal_error("Segment load command size is too small."); - - uint32_t NumSections = getSegmentLoadCommandNumSections(this, Load); - for (unsigned J = 0; J < NumSections; ++J) { + if (Load.C.cmdsize < SegmentLoadSize) { + EC = object_error::macho_load_segment_too_small; + return; + } + auto NumSectionsOrErr = getSegmentLoadCommandNumSections(this, Load); + if (!NumSectionsOrErr) { + EC = NumSectionsOrErr.getError(); + return; + } + for (unsigned J = 0; J < NumSectionsOrErr.get(); ++J) { const char *Sec = getSectionPtr(this, Load, J); Sections.push_back(Sec); } diff --git a/test/Object/macho-invalid.test b/test/Object/macho-invalid.test index 55b186dedd3..8bc11508dd5 100644 --- a/test/Object/macho-invalid.test +++ b/test/Object/macho-invalid.test @@ -15,13 +15,13 @@ RUN: not llvm-objdump -private-headers %p/Inputs/macho-invalid-too-small-segment RUN: | FileCheck -check-prefix SMALL-SEGLOADC-SIZE %s RUN: not llvm-objdump -private-headers %p/Inputs/macho64-invalid-too-small-segment-load-command 2>&1 \ RUN: | FileCheck -check-prefix SMALL-SEGLOADC-SIZE %s -SMALL-SEGLOADC-SIZE: Segment load command size is too small +SMALL-SEGLOADC-SIZE: Mach-O segment load command size is too small RUN: not llvm-objdump -private-headers %p/Inputs/macho-invalid-no-size-for-sections 2>&1 \ RUN: | FileCheck -check-prefix TOO-MANY-SECTS %s RUN: not llvm-objdump -private-headers %p/Inputs/macho64-invalid-no-size-for-sections 2>&1 \ RUN: | FileCheck -check-prefix TOO-MANY-SECTS %s -TOO-MANY-SECTS: Number of sections too large for size of load command +TOO-MANY-SECTS: Mach-O segment load command contains too many sections RUN: not llvm-objdump -t %p/Inputs/macho-invalid-bad-symbol-index 2>&1 \ RUN: | FileCheck -check-prefix BAD-SYMBOL %s -- 2.34.1