Follow debug link correctly

As thestig@chromium.org pointed out in https://breakpad.appspot.com/9684002,
LoadSymbols() should return false if |read_gnu_debug_link| is false.

BUG=chromium:453498
R=thestig@chromium.org

Review URL: https://breakpad.appspot.com/2844002

git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1422 4c0a9323-5329-0410-9bdc-e9ce6186880e
This commit is contained in:
hashimoto@chromium.org 2015-02-03 07:16:04 +00:00
parent 9f00bce09a
commit 854b9f74a0
2 changed files with 53 additions and 51 deletions

View file

@ -628,6 +628,35 @@ bool LoadSymbols(const string& obj_file,
"DWARF debugging information\n", obj_file.c_str());
}
}
// See if there are export symbols available.
const Shdr* dynsym_section =
FindElfSectionByName<ElfClass>(".dynsym", SHT_DYNSYM,
sections, names, names_end,
elf_header->e_shnum);
const Shdr* dynstr_section =
FindElfSectionByName<ElfClass>(".dynstr", SHT_STRTAB,
sections, names, names_end,
elf_header->e_shnum);
if (dynsym_section && dynstr_section) {
info->LoadedSection(".dynsym");
const uint8_t* dynsyms =
GetOffset<ElfClass, uint8_t>(elf_header,
dynsym_section->sh_offset);
const uint8_t* dynstrs =
GetOffset<ElfClass, uint8_t>(elf_header,
dynstr_section->sh_offset);
bool result =
ELFSymbolsToModule(dynsyms,
dynsym_section->sh_size,
dynstrs,
dynstr_section->sh_size,
big_endian,
ElfClass::kAddrSize,
module);
found_usable_info = found_usable_info || result;
}
}
if (options.symbol_data != NO_CFI) {
@ -689,8 +718,6 @@ bool LoadSymbols(const string& obj_file,
names_end, elf_header->e_shnum);
if (gnu_debuglink_section) {
if (!info->debug_dirs().empty()) {
found_debug_info_section = true;
const char* debuglink_contents =
GetOffset<ElfClass, char>(elf_header,
gnu_debuglink_section->sh_offset);
@ -709,45 +736,18 @@ bool LoadSymbols(const string& obj_file,
fprintf(stderr, "%s does not contain a .gnu_debuglink section.\n",
obj_file.c_str());
}
}
}
if (options.symbol_data != ONLY_CFI) {
const Shdr* dynsym_section =
FindElfSectionByName<ElfClass>(".dynsym", SHT_DYNSYM,
sections, names, names_end,
elf_header->e_shnum);
const Shdr* dynstr_section =
FindElfSectionByName<ElfClass>(".dynstr", SHT_STRTAB,
sections, names, names_end,
elf_header->e_shnum);
if (dynsym_section && dynstr_section) {
info->LoadedSection(".dynsym");
const uint8_t* dynsyms =
GetOffset<ElfClass, uint8_t>(elf_header,
dynsym_section->sh_offset);
const uint8_t* dynstrs =
GetOffset<ElfClass, uint8_t>(elf_header,
dynstr_section->sh_offset);
bool result =
ELFSymbolsToModule(dynsyms,
dynsym_section->sh_size,
dynstrs,
dynstr_section->sh_size,
big_endian,
ElfClass::kAddrSize,
module);
found_usable_info = found_usable_info || result;
}
}
if (read_gnu_debug_link) {
return found_debug_info_section;
}
// Return true if some usable information was found
} else {
// Return true if some usable information was found, since the caller
// doesn't want to use .gnu_debuglink.
return found_usable_info;
}
// No debug info was found, let the user try again with .gnu_debuglink
// if present.
return false;
}
return true;
}
// Return the breakpad symbol file identifier for the architecture of

View file

@ -79,6 +79,17 @@ void Module::AddFunction(Function *function) {
// FUNC lines must not hold an empty name, so catch the problem early if
// callers try to add one.
assert(!function->name.empty());
// FUNCs are better than PUBLICs as they come with sizes, so remove an extern
// with the same address if present.
Extern ext(function->address);
ExternSet::iterator it_ext = externs_.lower_bound(&ext);
if (it_ext != externs_.end() &&
(*it_ext)->address < function->address + function->size) {
delete *it_ext;
externs_.erase(it_ext);
}
std::pair<FunctionSet::iterator,bool> ret = functions_.insert(function);
if (!ret.second && (*ret.first != function)) {
// Free the duplicate that was not inserted because this Module
@ -98,21 +109,12 @@ void Module::AddStackFrameEntry(StackFrameEntry *stack_frame_entry) {
}
void Module::AddExtern(Extern *ext) {
Function func(ext->name, ext->address);
// Since parsing debug section and public info are not necessarily
// mutually exclusive, check if the symbol has already been read
// as a function to avoid duplicates.
if (functions_.find(&func) == functions_.end()) {
std::pair<ExternSet::iterator,bool> ret = externs_.insert(ext);
if (!ret.second) {
// Free the duplicate that was not inserted because this Module
// now owns it.
delete ext;
}
} else {
delete ext;
}
}
void Module::GetFunctions(vector<Function *> *vec,