[LLDB][Linux]Can not load the right module when loading a module having same name but different path with a loaded module

[LeoJialiang]

Some dynamic linker support to load module with the same name under different directories, like bionic.

When debugging a program which will link /PathA/liba.so by default, and it will dlopen /PathB/liba.so during runtime, the /PathB/liba.so can not be loaded correctly. LLDB will use /PathA/liba.so as the module of /PathB/liba.so. But /PathA/liba.so and /PathB/liba.so are different.

I find that, in Status NativeProcessLinux::GetLoadedModuleFileSpec , lldb will look for the module_path in the m_mem_region_cache, and just check the Filename without checking directory. This logic let lldb think two different so with same name the same.

Shall we change the NativeProcessLinux::GetLoadedModuleFileSpe to:
`Status NativeProcessLinux::GetLoadedModuleFileSpec(const char *module_path,
FileSpec &file_spec) {
Status error = PopulateMemoryRegionCache();
if (error.Fail())
return error;

FileSpec module_file_spec(module_path);
FileSystem::Instance().Resolve(module_file_spec);

file_spec.Clear();
for (const auto &it : m_mem_region_cache) {
if (it.second.GetFilename() == module_file_spec.GetFilename() &&
it.second.GetDirectory() == module_file_spec.GetDirectory()) {
file_spec = it.second;
return Status();
}
}
return Status("Module file (%s) not found in /proc/%" PRIu64 "/maps file!",
module_file_spec.GetFilename().AsCString(), GetID());
}`

I am not sure whether this change will make some other bug. Please take a look.

[llvmbot]

@llvm/issue-subscribers-lldb

Author: None (LeoJialiang)

Some dynamic linker support to load module with the same name under different directories, like bionic.

When debugging a program which will link /PathA/liba.so by default, and it will dlopen /PathB/liba.so during runtime, the /PathB/liba.so can not be loaded correctly. LLDB will use /PathA/liba.so as the module of /PathB/liba.so. But /PathA/liba.so and /PathB/liba.so are different.

I find that, in Status NativeProcessLinux::GetLoadedModuleFileSpec , lldb will look for the module_path in the m_mem_region_cache, and just check the Filename without checking directory. This logic let lldb think two different so with same name the same.

Shall we change the NativeProcessLinux::GetLoadedModuleFileSpe to:
`Status NativeProcessLinux::GetLoadedModuleFileSpec(const char *module_path,
FileSpec &file_spec) {
Status error = PopulateMemoryRegionCache();
if (error.Fail())
return error;

FileSpec module_file_spec(module_path);
FileSystem::Instance().Resolve(module_file_spec);

file_spec.Clear();
for (const auto &it : m_mem_region_cache) {
if (it.second.GetFilename() == module_file_spec.GetFilename() &&
it.second.GetDirectory() == module_file_spec.GetDirectory()) {
file_spec = it.second;
return Status();
}
}
return Status("Module file (%s) not found in /proc/%" PRIu64 "/maps file!",
module_file_spec.GetFilename().AsCString(), GetID());
}`

I am not sure whether this change will make some other bug. Please take a look.