[Lldb-commits] [lldb] r350809 - PECOFF: Fix section name computation
Pavel Labath via lldb-commits
lldb-commits at lists.llvm.org
Thu Jan 10 02:23:20 PST 2019
Author: labath
Date: Thu Jan 10 02:23:19 2019
New Revision: 350809
URL: http://llvm.org/viewvc/llvm-project?rev=350809&view=rev
Log:
PECOFF: Fix section name computation
If a section name is exactly 8 bytes long (or has been truncated to 8
bytes), it will not contain the terminating nul character. This means
reading the name as a c string will pick up random data following the
name field (which happens to be the section vm size).
This fixes the name computation to avoid out-of-bounds access and adds a
test.
Reviewers: zturner, stella.stamenova
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D56124
Added:
lldb/trunk/lit/Modules/PECOFF/sections-names.yaml
Modified:
lldb/trunk/source/Plugins/ObjectFile/PECOFF/ObjectFilePECOFF.cpp
lldb/trunk/source/Plugins/ObjectFile/PECOFF/ObjectFilePECOFF.h
Added: lldb/trunk/lit/Modules/PECOFF/sections-names.yaml
URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/lit/Modules/PECOFF/sections-names.yaml?rev=350809&view=auto
==============================================================================
--- lldb/trunk/lit/Modules/PECOFF/sections-names.yaml (added)
+++ lldb/trunk/lit/Modules/PECOFF/sections-names.yaml Thu Jan 10 02:23:19 2019
@@ -0,0 +1,52 @@
+# RUN: yaml2obj %s > %t
+# RUN: lldb-test object-file %t | FileCheck %s
+
+# CHECK: Name: .text{{$}}
+# CHECK: Name: 1234567{{$}}
+# CHECK: Name: 12345678{{$}}
+# CHECK: Name: 123456789{{$}}
+
+--- !COFF
+OptionalHeader:
+ AddressOfEntryPoint: 4616
+ ImageBase: 1073741824
+ SectionAlignment: 4096
+ FileAlignment: 512
+ MajorOperatingSystemVersion: 6
+ MinorOperatingSystemVersion: 0
+ MajorImageVersion: 0
+ MinorImageVersion: 0
+ MajorSubsystemVersion: 6
+ MinorSubsystemVersion: 0
+ Subsystem: IMAGE_SUBSYSTEM_WINDOWS_CUI
+ DLLCharacteristics: [ IMAGE_DLL_CHARACTERISTICS_HIGH_ENTROPY_VA, IMAGE_DLL_CHARACTERISTICS_DYNAMIC_BASE, IMAGE_DLL_CHARACTERISTICS_NX_COMPAT, IMAGE_DLL_CHARACTERISTICS_TERMINAL_SERVER_AWARE ]
+ SizeOfStackReserve: 1048576
+ SizeOfStackCommit: 4096
+ SizeOfHeapReserve: 1048576
+ SizeOfHeapCommit: 4096
+header:
+ Machine: IMAGE_FILE_MACHINE_AMD64
+ Characteristics: [ IMAGE_FILE_EXECUTABLE_IMAGE, IMAGE_FILE_LARGE_ADDRESS_AWARE ]
+sections:
+ - Name: .text
+ Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ]
+ VirtualAddress: 4096
+ VirtualSize: 64 # '@', if it makes its way into the name field
+ SectionData: DEADBEEFBAADF00D
+ - Name: 1234567
+ Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_READ ]
+ VirtualAddress: 442368
+ VirtualSize: 64
+ SectionData: DEADBEEFBAADF00D
+ - Name: 12345678
+ Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_READ ]
+ VirtualAddress: 446464
+ VirtualSize: 64
+ SectionData: DEADBEEFBAADF00D
+ - Name: 123456789
+ Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_READ ]
+ VirtualAddress: 450560
+ VirtualSize: 64
+ SectionData: DEADBEEFBAADF00D
+symbols: []
+...
Modified: lldb/trunk/source/Plugins/ObjectFile/PECOFF/ObjectFilePECOFF.cpp
URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Plugins/ObjectFile/PECOFF/ObjectFilePECOFF.cpp?rev=350809&r1=350808&r2=350809&view=diff
==============================================================================
--- lldb/trunk/source/Plugins/ObjectFile/PECOFF/ObjectFilePECOFF.cpp (original)
+++ lldb/trunk/source/Plugins/ObjectFile/PECOFF/ObjectFilePECOFF.cpp Thu Jan 10 02:23:19 2019
@@ -530,22 +530,20 @@ bool ObjectFilePECOFF::ParseSectionHeade
return !m_sect_headers.empty();
}
-bool ObjectFilePECOFF::GetSectionName(std::string §_name,
- const section_header_t §) {
- if (sect.name[0] == '/') {
- lldb::offset_t stroff = strtoul(§.name[1], NULL, 10);
+llvm::StringRef ObjectFilePECOFF::GetSectionName(const section_header_t §) {
+ llvm::StringRef hdr_name(sect.name, llvm::array_lengthof(sect.name));
+ hdr_name = hdr_name.split('\0').first;
+ if (hdr_name.consume_front("/")) {
+ lldb::offset_t stroff;
+ if (!to_integer(hdr_name, stroff, 10))
+ return "";
lldb::offset_t string_file_offset =
m_coff_header.symoff + (m_coff_header.nsyms * 18) + stroff;
- const char *name = m_data.GetCStr(&string_file_offset);
- if (name) {
- sect_name = name;
- return true;
- }
-
- return false;
+ if (const char *name = m_data.GetCStr(&string_file_offset))
+ return name;
+ return "";
}
- sect_name = sect.name;
- return true;
+ return hdr_name;
}
//----------------------------------------------------------------------
@@ -712,9 +710,7 @@ void ObjectFilePECOFF::CreateSections(Se
const uint32_t nsects = m_sect_headers.size();
ModuleSP module_sp(GetModule());
for (uint32_t idx = 0; idx < nsects; ++idx) {
- std::string sect_name;
- GetSectionName(sect_name, m_sect_headers[idx]);
- ConstString const_sect_name(sect_name.c_str());
+ ConstString const_sect_name(GetSectionName(m_sect_headers[idx]));
static ConstString g_code_sect_name(".code");
static ConstString g_CODE_sect_name("CODE");
static ConstString g_data_sect_name(".data");
@@ -1086,8 +1082,7 @@ void ObjectFilePECOFF::DumpOptCOFFHeader
//----------------------------------------------------------------------
void ObjectFilePECOFF::DumpSectionHeader(Stream *s,
const section_header_t &sh) {
- std::string name;
- GetSectionName(name, sh);
+ std::string name = GetSectionName(sh);
s->Printf("%-16s 0x%8.8x 0x%8.8x 0x%8.8x 0x%8.8x 0x%8.8x 0x%8.8x 0x%4.4x "
"0x%4.4x 0x%8.8x\n",
name.c_str(), sh.vmaddr, sh.vmsize, sh.offset, sh.size, sh.reloff,
Modified: lldb/trunk/source/Plugins/ObjectFile/PECOFF/ObjectFilePECOFF.h
URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Plugins/ObjectFile/PECOFF/ObjectFilePECOFF.h?rev=350809&r1=350808&r2=350809&view=diff
==============================================================================
--- lldb/trunk/source/Plugins/ObjectFile/PECOFF/ObjectFilePECOFF.h (original)
+++ lldb/trunk/source/Plugins/ObjectFile/PECOFF/ObjectFilePECOFF.h Thu Jan 10 02:23:19 2019
@@ -270,7 +270,7 @@ protected:
void DumpSectionHeader(lldb_private::Stream *s, const section_header_t &sh);
void DumpDependentModules(lldb_private::Stream *s);
- bool GetSectionName(std::string §_name, const section_header_t §);
+ llvm::StringRef GetSectionName(const section_header_t §);
typedef std::vector<section_header_t> SectionHeaderColl;
typedef SectionHeaderColl::iterator SectionHeaderCollIter;
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