Author: Rumeet Dhindsa Date: 2021-08-24T13:41:22-07:00 New Revision: 1cbdc07ec015d83038c08dc562d55eccfd808591
URL: https://github.com/llvm/llvm-project/commit/1cbdc07ec015d83038c08dc562d55eccfd808591 DIFF: https://github.com/llvm/llvm-project/commit/1cbdc07ec015d83038c08dc562d55eccfd808591.diff LOG: [lldb] Add support for debugging via the dynamic linker. This patch adds support for shared library load when the executable is called through ld.so. Differential Revision:https://reviews.llvm.org/D108061 Added: lldb/test/API/functionalities/dyld-launch-linux/Makefile lldb/test/API/functionalities/dyld-launch-linux/TestDyldLaunchLinux.py lldb/test/API/functionalities/dyld-launch-linux/main.cpp lldb/test/API/functionalities/dyld-launch-linux/signal_file.cpp lldb/test/API/functionalities/dyld-launch-linux/signal_file.h Modified: lldb/source/Plugins/DynamicLoader/POSIX-DYLD/DYLDRendezvous.cpp lldb/source/Plugins/DynamicLoader/POSIX-DYLD/DynamicLoaderPOSIXDYLD.cpp Removed: ################################################################################ diff --git a/lldb/source/Plugins/DynamicLoader/POSIX-DYLD/DYLDRendezvous.cpp b/lldb/source/Plugins/DynamicLoader/POSIX-DYLD/DYLDRendezvous.cpp index 866acbddbdc8..e385b583cef9 100644 --- a/lldb/source/Plugins/DynamicLoader/POSIX-DYLD/DYLDRendezvous.cpp +++ b/lldb/source/Plugins/DynamicLoader/POSIX-DYLD/DYLDRendezvous.cpp @@ -56,6 +56,19 @@ static addr_t ResolveRendezvousAddress(Process *process) { "%s resolved via direct object file approach to 0x%" PRIx64, __FUNCTION__, info_location); } else { + const Symbol *_r_debug = + target->GetExecutableModule()->FindFirstSymbolWithNameAndType( + ConstString("_r_debug")); + if (_r_debug) { + info_addr = _r_debug->GetAddress().GetLoadAddress(target); + if (info_addr != LLDB_INVALID_ADDRESS) { + LLDB_LOGF(log, + "%s resolved by finding symbol '_r_debug' whose value is " + "0x%" PRIx64, + __FUNCTION__, info_addr); + return info_addr; + } + } LLDB_LOGF(log, "%s FAILED - direct object file approach did not yield a " "valid address", @@ -276,6 +289,14 @@ bool DYLDRendezvous::FillSOEntryFromModuleInfo( entry.base_addr = base_addr; entry.dyn_addr = dyn_addr; + // ld.so saves empty file name for the executable file in the link map. + // When executable is run using ld.so, we need to be update executable path. + if (name.empty()) { + MemoryRegionInfo region; + Status region_status = + m_process->GetMemoryRegionInfo(entry.dyn_addr, region); + name = region.GetName().AsCString(); + } entry.file_spec.SetFile(name, FileSpec::Style::native); UpdateBaseAddrIfNecessary(entry, name); @@ -547,6 +568,15 @@ bool DYLDRendezvous::ReadSOEntryFromMemory(lldb::addr_t addr, SOEntry &entry) { return false; std::string file_path = ReadStringFromMemory(entry.path_addr); + + // ld.so saves empty file name for the executable file in the link map. + // When executable is run using ld.so, we need to be update executable path. + if (file_path.empty()) { + MemoryRegionInfo region; + Status region_status = + m_process->GetMemoryRegionInfo(entry.dyn_addr, region); + file_path = region.GetName().AsCString(); + } entry.file_spec.SetFile(file_path, FileSpec::Style::native); UpdateBaseAddrIfNecessary(entry, file_path); diff --git a/lldb/source/Plugins/DynamicLoader/POSIX-DYLD/DynamicLoaderPOSIXDYLD.cpp b/lldb/source/Plugins/DynamicLoader/POSIX-DYLD/DynamicLoaderPOSIXDYLD.cpp index 160faa74af23..09d0523f676c 100644 --- a/lldb/source/Plugins/DynamicLoader/POSIX-DYLD/DynamicLoaderPOSIXDYLD.cpp +++ b/lldb/source/Plugins/DynamicLoader/POSIX-DYLD/DynamicLoaderPOSIXDYLD.cpp @@ -333,28 +333,48 @@ bool DynamicLoaderPOSIXDYLD::SetRendezvousBreakpoint() { LLDB_LOG(log, "Rendezvous structure is not set up yet. " "Trying to locate rendezvous breakpoint in the interpreter " "by symbol name."); - ModuleSP interpreter = LoadInterpreterModule(); - if (!interpreter) { - LLDB_LOG(log, "Can't find interpreter, rendezvous breakpoint isn't set."); - return false; - } - - // Function names from diff erent dynamic loaders that are known to be used - // as rendezvous between the loader and debuggers. + // Function names from diff erent dynamic loaders that are known to be + // used as rendezvous between the loader and debuggers. static std::vector<std::string> DebugStateCandidates{ "_dl_debug_state", "rtld_db_dlactivity", "__dl_rtld_db_dlactivity", "r_debug_state", "_r_debug_state", "_rtld_debug_state", }; - FileSpecList containingModules; - containingModules.Append(interpreter->GetFileSpec()); - dyld_break = target.CreateBreakpoint( - &containingModules, nullptr /* containingSourceFiles */, - DebugStateCandidates, eFunctionNameTypeFull, eLanguageTypeC, - 0, /* offset */ - eLazyBoolNo, /* skip_prologue */ - true, /* internal */ - false /* request_hardware */); + ModuleSP interpreter = LoadInterpreterModule(); + if (!interpreter) { + if (NameMatches(m_process->GetTarget() + .GetExecutableModulePointer() + ->GetFileSpec() + .GetFilename() + .GetCString(), + NameMatch::StartsWith, "ld-")) { + FileSpecList containingModules; + containingModules.Append( + m_process->GetTarget().GetExecutableModulePointer()->GetFileSpec()); + + dyld_break = target.CreateBreakpoint( + &containingModules, /*containingSourceFiles=*/nullptr, + DebugStateCandidates, eFunctionNameTypeFull, eLanguageTypeC, + /*offset=*/0, + /*skip_prologue=*/eLazyBoolNo, + /*internal=*/true, + /*request_hardware=*/false); + } else { + LLDB_LOG(log, + "Can't find interpreter, rendezvous breakpoint isn't set."); + return false; + } + } else { + FileSpecList containingModules; + containingModules.Append(interpreter->GetFileSpec()); + dyld_break = target.CreateBreakpoint( + &containingModules, /*containingSourceFiles=*/nullptr, + DebugStateCandidates, eFunctionNameTypeFull, eLanguageTypeC, + /*offset=*/0, + /*skip_prologue=*/eLazyBoolNo, + /*internal=*/true, + /*request_hardware=*/false); + } } if (dyld_break->GetNumResolvedLocations() != 1) { diff --git a/lldb/test/API/functionalities/dyld-launch-linux/Makefile b/lldb/test/API/functionalities/dyld-launch-linux/Makefile new file mode 100644 index 000000000000..36bfbb52590d --- /dev/null +++ b/lldb/test/API/functionalities/dyld-launch-linux/Makefile @@ -0,0 +1,15 @@ +CXX_SOURCES := main.cpp +LD_EXTRAS := -Wl,-rpath "-Wl,$(shell pwd)" +USE_LIBDL := 1 + +include Makefile.rules + +# The following shared library will be used to test breakpoints under dynamic loading +libsignal_file.so: signal_file.cpp + $(MAKE) -f $(MAKEFILE_RULES) \ + DYLIB_ONLY=YES DYLIB_CXX_SOURCES=signal_file.cpp DYLIB_NAME=signal_file + +a.out: libsignal_file.so main.cpp + $(MAKE) -f $(MAKEFILE_RULES) \ + CXX_SOURCES=main.cpp LD_EXTRAS=libsignal_file.so + diff --git a/lldb/test/API/functionalities/dyld-launch-linux/TestDyldLaunchLinux.py b/lldb/test/API/functionalities/dyld-launch-linux/TestDyldLaunchLinux.py new file mode 100644 index 000000000000..bf7ce12effc4 --- /dev/null +++ b/lldb/test/API/functionalities/dyld-launch-linux/TestDyldLaunchLinux.py @@ -0,0 +1,46 @@ +""" +Test that LLDB can launch a linux executable through the dynamic loader and still hit a breakpoint. +""" + +import lldb +import os + +from lldbsuite.test.lldbtest import * + +class TestLinux64LaunchingViaDynamicLoader(TestBase): + mydir = TestBase.compute_mydir(__file__) + + def test(self): + self.build() + exe = "/lib64/ld-linux-x86-64.so.2" + if(os.path.exists(exe)): + target = self.dbg.CreateTarget(exe) + self.assertTrue(target, VALID_TARGET) + + # Set breakpoints both on shared library function as well as on + # main. Both of them will be pending breakpoints. + breakpoint_main = target.BreakpointCreateBySourceRegex("// Break here", lldb.SBFileSpec("main.cpp")) + breakpoint_shared_library = target.BreakpointCreateBySourceRegex("get_signal_crash", lldb.SBFileSpec("signal_file.cpp")) + launch_info = lldb.SBLaunchInfo([ "--library-path",self.get_process_working_directory(),self.getBuildArtifact("a.out")]) + launch_info.SetWorkingDirectory(self.get_process_working_directory()) + error = lldb.SBError() + process = target.Launch(launch_info,error) + self.assertTrue(error.Success()) + + # Stopped on main here. + self.assertEqual(process.GetState(), lldb.eStateStopped) + thread = process.GetSelectedThread() + self.assertIn("main",thread.GetFrameAtIndex(0).GetDisplayFunctionName()) + process.Continue() + + # Stopped on get_signal_crash function here. + self.assertEqual(process.GetState(), lldb.eStateStopped) + self.assertIn("get_signal_crash",thread.GetFrameAtIndex(0).GetDisplayFunctionName()) + process.Continue() + + # Stopped because of generated signal. + self.assertEqual(process.GetState(), lldb.eStateStopped) + self.assertIn("raise",thread.GetFrameAtIndex(0).GetDisplayFunctionName()) + self.assertIn("get_signal_crash",thread.GetFrameAtIndex(1).GetDisplayFunctionName()) + + diff --git a/lldb/test/API/functionalities/dyld-launch-linux/main.cpp b/lldb/test/API/functionalities/dyld-launch-linux/main.cpp new file mode 100644 index 000000000000..0ff05466c58c --- /dev/null +++ b/lldb/test/API/functionalities/dyld-launch-linux/main.cpp @@ -0,0 +1,6 @@ +#include "signal_file.h" + +int main() { + // Break here + return get_signal_crash(); +} diff --git a/lldb/test/API/functionalities/dyld-launch-linux/signal_file.cpp b/lldb/test/API/functionalities/dyld-launch-linux/signal_file.cpp new file mode 100644 index 000000000000..3c904a34f421 --- /dev/null +++ b/lldb/test/API/functionalities/dyld-launch-linux/signal_file.cpp @@ -0,0 +1,7 @@ +#include "signal_file.h" +#include <signal.h> + +int get_signal_crash(void) { + raise(SIGSEGV); + return 0; +} diff --git a/lldb/test/API/functionalities/dyld-launch-linux/signal_file.h b/lldb/test/API/functionalities/dyld-launch-linux/signal_file.h new file mode 100644 index 000000000000..7c8676f71109 --- /dev/null +++ b/lldb/test/API/functionalities/dyld-launch-linux/signal_file.h @@ -0,0 +1 @@ +int get_signal_crash(void); _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits
