[Pal] Rewrite GDB integration, part 1

For now only gdb-script and Python parts. This is mostly a clean-up of
both Linux and Linux-SGX integration which additionally removes some
annoying user prompts we had in the old scripts.

.ci/prfilter

@@ -33,7 +33,7 @@ THE_BIG_LIST_OF_NAUGHTY_FILES = list(map(pathlib.Path, [
     'LibOS/shim/test/regression/test_libos.py',
     'Pal/regression/test_pal.py',
     'Pal/src/host/Linux-SGX/sgx-driver/link-intel-driver.py',
-    'Pal/src/host/Linux/pal-gdb.py',
+    'Pal/src/host/Linux/gdb_integration/graphene_gdb.py',
     'Scripts/regression.py',
     'Tools',
 ]))

.ci/run-shellcheck

@@ -8,7 +8,6 @@ shellcheck "$@" \
     Examples/bash/scripts/bash_test.sh \
     Examples/common_tools/benchmark-http.sh \
     Examples/python-simple/run-tests.sh \
-    Pal/src/host/Linux-SGX/debugger/gdb \
     Runtime/pal_loader \
     Scripts/clean-check \
     Scripts/clean-check-prepare \

Pal/src/Makefile

@@ -11,7 +11,6 @@ pal_lib =
 pal_lib_deps =
 pal_lib_post =
 pal_static =
-pal_gdb =
 
 HOST_DIR = host/$(PAL_HOST)
 LIB_DIR = $(HOST_DIR)/.lib
@@ -63,7 +62,6 @@ host_lib = $(HOST_DIR)/libpal-$(PAL_HOST).a
 # Install Targets (all in RUNTIME_DIR):
 #       pal-{Host Name}:       loader for PAL (as an executable)
 #       libpal-{Host Name}.so: dynamic-linking library
-#       pal_gdb-{Host Name}:   debugger for PAL (as an executable)
 
 ifneq ($(pal_loader),)
 	runtime_loader += $(RUNTIME_DIR)/pal-$(PAL_HOST)
@@ -73,11 +71,7 @@ ifneq ($(pal_lib),)
 	runtime_lib += $(RUNTIME_DIR)/libpal-$(PAL_HOST)$(suffix $(pal_lib))
 endif
 
-ifneq ($(pal_gdb),)
-	runtime_gdb += $(RUNTIME_DIR)/pal_gdb-$(PAL_HOST)
-endif
-
-files_to_install = $(runtime_loader) $(runtime_lib) $(runtime_sec) $(runtime_gdb)
+files_to_install = $(runtime_loader) $(runtime_lib) $(runtime_sec)
 
 
 ###########################
@@ -117,11 +111,6 @@ $(runtime_lib): $(pal_lib)
 	$(call cmd,ln_sfr)
 endif
 
-ifneq ($(pal_gdb),)
-$(runtime_gdb): $(pal_gdb)
-	$(call cmd,ln_sfr)
-endif
-
 ifneq ($(pal_lib_post),)
 $(pal_lib_post): $(pal_lib)
 	@$(MAKE) -C $(HOST_DIR) $@

Pal/src/host/Linux-SGX/Makefile

@@ -23,7 +23,7 @@ ASFLAGS += \
 	-I../../../include \
 	-I../../../include/arch/$(ARCH)/Linux
 
-host_files = libpal-Linux-SGX.a pal-sgx debugger/sgx_gdb.so pal.map generated_offsets.py
+host_files = libpal-Linux-SGX.a pal-sgx gdb_integration/sgx_gdb.so pal.map generated_offsets.py
 
 defs	= -DIN_PAL
 CFLAGS += $(defs)
@@ -73,7 +73,7 @@ urts-objs = \
 	sgx_main.o \
 	sgx_platform.o \
 	sgx_process.o \
-	sgx_rtld.o \
+	sgx_gdb_info.o \
 	sgx_thread.o \
 	quote/aesm.pb-c.o \
 	$(commons_objs_urts)
@@ -125,9 +125,9 @@ quote/aesm.pb-c.c quote/aesm.pb-c.h: quote/aesm.proto
 	@echo [ host/Linux-SGX/quote/aesm.pb-c.h ]
 	@protoc-c --c_out=. $<
 
-debugger/sgx_gdb.so: CFLAGS =
-CFLAGS-debugger/sgx_gdb.so = -shared -Wall -fPIC -O2 -std=c11
-debugger/sgx_gdb.so: debugger/sgx_gdb.c
+gdb_integration/sgx_gdb.so: CFLAGS =
+CFLAGS-gdb_integration/sgx_gdb.so = -shared -Wall -fPIC -O2 -std=c11
+gdb_integration/sgx_gdb.so: gdb_integration/sgx_gdb.c
 	$(call cmd,csingle)
 
 enclave_entry.o sgx_entry.o: asm-offsets.h
@@ -136,7 +136,7 @@ sgx-driver/sgx.h:
 	$(MAKE) -C sgx-driver $(notdir $@)
 
 ifeq ($(filter %clean,$(MAKECMDGOALS)),)
-include $(wildcard *.d) $(wildcard debugger/*.d)
+include $(wildcard *.d) $(wildcard gdb_integration/*.d)
 endif
 
 include ../../../../Scripts/Makefile.rules
@@ -146,13 +146,13 @@ tools:
 	$(MAKE) -C tools
 
 CLEAN_FILES += $(notdir $(pal_static) $(pal_lib) $(pal_loader))
-CLEAN_FILES += debugger/sgx_gdb.so
+CLEAN_FILES += gdb_integration/sgx_gdb.so
 CLEAN_FILES += quote/aesm.pb-c.c quote/aesm.pb-c.h quote/aesm.pb-c.d quote/aesm.pb-c.o
 
 .PHONY: clean_
 clean_:
-	$(RM) -r *.o *.e *.i *.s $(host_files) $(CLEAN_FILES) *.d debugger/*.d signer/*.pyc __pycache__ \
-	         signer/__pycache__
+	$(RM) -r *.o *.e *.i *.s $(host_files) $(CLEAN_FILES) *.d gdb_integration/*.d signer/*.pyc \
+	         __pycache__ signer/__pycache__
 	$(RM) -r protected-files/*.o protected-files/*.d
 
 .PHONY: clean

Pal/src/host/Linux-SGX/Makefile.am

@@ -18,5 +18,4 @@ pal_loader = $(HOST_DIR)/pal-sgx
 pal_lib = $(HOST_DIR)/libpal.so
 pal_lib_deps = pal-symbols $(HOST_DIR)/pal.map.template $(HOST_DIR)/enclave.lds
 pal_static = $(HOST_DIR)/libpal.a
-pal_gdb = $(HOST_DIR)/debugger/gdb
 pal_signer = pal-sgx-get-token pal-sgx-sign aesm_pb2.py

Pal/src/host/Linux-SGX/debugger/gdb

@@ -1,10 +0,0 @@
-#!/usr/bin/env bash
-
-DIR="$(dirname "$(readlink -f "${BASH_SOURCE[0]}")")"
-GDB_SCRIPT=$DIR/pal-gdb.py
-GDB_SO=$DIR/sgx_gdb.so
-if [ -z "$INSIDE_EMACS" ]; then
-	set -x
-fi
-
-LD_PRELOAD=$GDB_SO gdb -iex "add-auto-load-safe-path $GDB_SCRIPT" "$@"

Pal/src/host/Linux-SGX/debugger/pal-gdb.py

@@ -1,49 +0,0 @@
-#!/usr/bin/env python3
-# pylint: disable=invalid-name
-
-import gdb # pylint: disable=import-error
-
-# pylint: enable=invalid-name
-# pylint: disable=no-self-use,too-few-public-methods
-
-class LoadCommandBreakpoint(gdb.Breakpoint):
-    def __init__(self):
-        gdb.Breakpoint.__init__(self, spec="load_gdb_command", internal=1)
-
-    def stop(self):
-        command = gdb.parse_and_eval("(const char *) $rdi").string()
-        gdb.execute(command)
-        return False
-
-def signal_handler(event):
-    if isinstance(event, gdb.SignalEvent):
-        if event.stop_signal == 'SIGILL':
-            # handle CPUINFO and RDTSC
-            inst = gdb.parse_and_eval("*(const unsigned short *) $rip")
-            if inst == 0xa20f:
-                print("CPUID bypassed. Ignore this exception.")
-                gdb.execute("continue")
-                return
-            if inst == 0x310f:
-                print("RDTSC bypassed. Ignore this exception.")
-                gdb.execute("continue")
-                return
-
-if __name__ == "__main__":
-    gdb.execute("set env IN_GDB = 1")
-    gdb.execute("set env LD_PRELOAD = ")
-
-    gdb.execute("handle SIGCONT pass noprint nostop")
-    gdb.execute("handle SIGKILL pass print stop")
-
-    gdb.execute("set disable-randomization off")
-    gdb.execute("set detach-on-fork off")
-    gdb.execute("set schedule-multiple on")
-    gdb.execute("set follow-exec-mode same")
-    gdb.execute("set follow-fork-mode child")
-
-    # Need to disable displaced stepping
-    gdb.execute("set displaced-stepping off")
-
-    LoadCommandBreakpoint()
-    gdb.events.stop.connect(signal_handler)

Pal/src/host/Linux-SGX/gdb_integration/graphene_sgx.gdb

@@ -0,0 +1,63 @@
+# SPDX-License-Identifier: LGPL-3.0-or-later */
+# Copyright (C) 2020 Intel Corporation
+#                    Michał Kowalczyk <mkow@invisiblethingslab.com>
+
+
+# GDB Python "API" [1] is so wonderful that what we need [2] is not possible to be implemented using
+# it, so we have to fall back to raw GDB scripting. But raw GDB scripting is also broken, so we need
+# to supply things like `push-pagination` command from Python.
+#
+# [1] It mostly consists of `gdb.execute()`, there isn't even gdb.continue() API, you need to call
+#     `gdb.execute('continue')`.
+# [2] One of the things we want is to silently pass SIGILLs caused by CPUID and RDTSC to the
+#     application, but without silencing SIGILLs caused by other reasons. This is impossible to
+#     implement from GDB Python "API", neither using event handlers nor even executing raw commands
+#     with gdb.execute() - it doesn't support multiline commands, and gdb.execute('commands') blocks
+#     for input on the *user terminal*, not giving the script a chance to provide more lines.
+
+
+# Prevent the preloaded sgx_gdb.so from being preloaded to the debuggee.
+set env LD_PRELOAD=
+
+# Tell Graphene to behave more gdb-friendly.
+set env IN_GDB=1
+
+# Used internally by Graphene, generates a lot of noise if we don't silence it.
+handle SIGCONT pass noprint nostop
+
+# TODO: This block of commands was copied from an older Graphene integration script where they
+# didn't have any comments with rationale why they are needed. We should revise and comment them.
+handle SIGKILL pass print stop
+set disable-randomization off
+set detach-on-fork off
+set schedule-multiple on
+set follow-exec-mode same
+set follow-fork-mode child
+set displaced-stepping off
+
+
+# CPUID/RDTSC SIGILL skipping. See [2] above.
+
+catch signal SIGILL
+
+# break only on CPUID (0fa2) and RDTSC (0f31)
+condition $bpnum *(uint16_t*)$rip == 0xa20f || *(uint16_t*)$rip == 0x310f
+
+commands
+    silent
+
+    # If we don't disable pagination then successive prints from this handler (even despite it's
+    # called for different events) will stop and prompt the user for continuation, which is really
+    # annoying.
+    push-pagination off
+
+    if *(uint16_t*)$rip == 0xa20f
+        echo [graphene_sgx.gdb] Passing SIGILL caused by CPUID to the enclave\n
+    end
+    if *(uint16_t*)$rip == 0x310f
+        echo [graphene_sgx.gdb] Passing SIGILL caused by RDTSC to the enclave\n
+    end
+
+    pop-pagination
+    continue
+end

Pal/src/host/Linux-SGX/gdb_integration/graphene_sgx_gdb.py

@@ -0,0 +1,71 @@
+# SPDX-License-Identifier: LGPL-3.0-or-later */
+# Copyright (C) 2020 Intel Corporation
+#                    Michał Kowalczyk <mkow@invisiblethingslab.com>
+
+import os
+
+import gdb # pylint: disable=import-error
+
+# pylint: disable=no-self-use,too-few-public-methods
+
+_g_paginations = []
+
+class PushPagination(gdb.Command):
+    """Temporarily changing pagination and saving the old state.
+
+    Supplements gdb interface with functionality it's missing and seems to not be possible to
+    implement from a gdb script. This command is used by graphene_sgx.gdb script.
+    """
+
+    def __init__(self):
+        super(PushPagination, self).__init__("push-pagination", gdb.COMMAND_USER)
+
+    def invoke(self, arg, _from_tty):
+        self.dont_repeat()
+
+        pagination_str = gdb.execute('show pagination', to_string=True).strip()
+        assert pagination_str in ('State of pagination is on.', 'State of pagination is off.')
+        pagination = pagination_str.endswith('on.')
+        _g_paginations.append(pagination)
+
+        assert arg in ('on', 'off')
+        gdb.execute('set pagination ' + arg)
+
+
+class PopPagination(gdb.Command):
+    """Recover pagination state saved by PushPagination"""
+
+    def __init__(self):
+        super(PopPagination, self).__init__("pop-pagination", gdb.COMMAND_USER)
+
+    def invoke(self, arg, _from_tty):
+        self.dont_repeat()
+
+        assert arg == ''
+        pagination = _g_paginations.pop()
+        gdb.execute('set pagination ' + ('on' if pagination else 'off'))
+
+
+class LoadCommandBreakpoint(gdb.Breakpoint):
+    def __init__(self):
+        gdb.Breakpoint.__init__(self, spec="execute_gdb_command", internal=1)
+
+    def stop(self):
+        command = gdb.parse_and_eval("(const char*)$rdi").string()
+        gdb.execute(command)
+        return False
+
+def main():
+    PushPagination()
+    PopPagination()
+
+    # Some of the things we want to do can't be done using gdb Python API, we need to fall back to a
+    # standard gdb script.
+    gdb_script = os.path.dirname(__file__) + "/graphene_sgx.gdb"
+    print("[%s] Loading %s..." % (os.path.basename(__file__), gdb_script))
+    gdb.execute("source " + gdb_script)
+
+    LoadCommandBreakpoint()
+
+if __name__ == "__main__":
+    main()

Pal/src/host/Linux-SGX/gdb_integration/sgx_gdb.c

@@ -333,7 +333,7 @@ static int open_memdevice(pid_t tid, int* memdev, struct enclave_dbginfo** ei) {
     for (int i = 0; i < g_memdevs_cnt; i++) {
         if (g_memdevs[i].pid == tid) {
             *memdev = g_memdevs[i].memdev;
-            *ei     = &g_memdevs[i].ei;
+            *ei = &g_memdevs[i].ei;
             return update_thread_tids(*ei);
         }
     }
@@ -356,7 +356,7 @@ static int open_memdevice(pid_t tid, int* memdev, struct enclave_dbginfo** ei) {
     for (int i = 0; i < g_memdevs_cnt; i++) {
         if (g_memdevs[i].pid == eib.pid) {
             *memdev = g_memdevs[i].memdev;
-            *ei     = &g_memdevs[i].ei;
+            *ei = &g_memdevs[i].ei;
             return update_thread_tids(*ei);
         }
     }
@@ -408,7 +408,7 @@ static int open_memdevice(pid_t tid, int* memdev, struct enclave_dbginfo** ei) {
            sizeof(g_memdevs[g_memdevs_cnt].ei.thread_stepping));
 
     *memdev = fd;
-    *ei     = &g_memdevs[g_memdevs_cnt].ei;
+    *ei = &g_memdevs[g_memdevs_cnt].ei;
     g_memdevs_cnt++;
 
     return 0;

Pal/src/host/Linux-SGX/sgx_enclave.c

@@ -632,7 +632,7 @@ static long sgx_ocall_eventfd(void* pms) {
 static long sgx_ocall_load_debug(void* pms) {
     const char* command = (const char*)pms;
     ODEBUG(OCALL_LOAD_DEBUG, (void*)command);
-    load_gdb_command(command);
+    execute_gdb_command(command);
     return 0;
 }
 

Pal/src/host/Linux-SGX/sgx_gdb_info.c

@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/* Copyright (C) 2020 Intel Corporation
+ *                    Michał Kowalczyk <mkow@invisiblethingslab.com>
+ */
+
+#include "pal_debug.h"
+#include "sgx_internal.h"
+
+/* This function is hooked by our gdb integration script and should be left as is. */
+__attribute__((__noinline__)) void execute_gdb_command(const char* command) {
+    __UNUSED(command);
+    __asm__ volatile(""); // Required in addition to __noinline__ to prevent deleting this function.
+                          // See GCC docs.
+}

Pal/src/host/Linux-SGX/sgx_internal.h

@@ -138,6 +138,6 @@ int sgx_signal_setup(void);
 int block_signals(bool block, const int* sigs, int nsig);
 int block_async_signals(bool block);
 
-void load_gdb_command(const char* command);
+void execute_gdb_command(const char* command);
 
 #endif

Pal/src/host/Linux-SGX/sgx_main.c

@@ -8,7 +8,7 @@
 #include "pal_rtld.h"
 #include "hex.h"
 
-#include "debugger/sgx_gdb.h"
+#include "gdb_integration/sgx_gdb.h"
 #include "linux_utils.h"
 #include "rpc_queue.h"
 #include "sgx_api.h"

Pal/src/host/Linux-SGX/sgx_rtld.c

@@ -1,27 +0,0 @@
-/* SPDX-License-Identifier: LGPL-3.0-or-later */
-/* Copyright (C) 2014 Stony Brook University */
-
-/*
- * db_rtld.c
- *
- * This file contains utilities to load ELF binaries into the memory
- * and link them against each other.
- * The source code in this file is imported and modified from the GNU C
- * Library.
- */
-
-#include "api.h"
-#include "pal_internal.h"
-#include "sgx_internal.h"
-
-__asm__(
-    ".pushsection \".debug_gdb_scripts\", \"MS\",@progbits,1\r\n"
-    ".byte 1\r\n"
-    ".asciz \"debugger/pal-gdb.py\"\r\n"
-    ".popsection\r\n");
-
-/* This function is hooked by our gdb integration script and should be
- * left as is. */
-void load_gdb_command(const char* command) {
-    __UNUSED(command);
-}

Pal/src/host/Linux-SGX/sgx_thread.c

@@ -11,7 +11,7 @@
 #include <linux/signal.h>
 
 #include "assert.h"
-#include "debugger/sgx_gdb.h"
+#include "gdb_integration/sgx_gdb.h"
 #include "pal_internal.h"
 #include "pal_security.h"
 #include "sgx_enclave.h"

Pal/src/host/Linux/Makefile.am

@@ -17,4 +17,3 @@ pal_lib = $(HOST_DIR)/libpal.so
 pal_lib_deps = pal-symbols $(HOST_DIR)/pal.map.template $(HOST_DIR)/pal-$(ARCH).lds
 pal_lib_post =
 pal_static = $(HOST_DIR)/libpal.a
-pal_gdb =

Pal/src/host/Linux/db_main.c

@@ -30,15 +30,6 @@
 /* pal_start is the entry point of libpal.so, which calls pal_main */
 #define _ENTRY pal_start
 
-/* use objfile-gdb convention instead of .debug_gdb_scripts */
-#ifdef DEBUG
-__asm__(
-    ".pushsection \".debug_gdb_scripts\", \"MS\",@progbits,1\r\n"
-    ".byte 1\r\n"
-    ".asciz \"pal-gdb.py\"\r\n"
-    ".popsection\r\n");
-#endif
-
 char* g_pal_loader_path = NULL;
 /* Currently content of this variable is only passed as an argument while spawning new processes
  * - this is to keep uniformity with other PALs. */

Pal/src/host/Linux/gdb_integration/graphene.gdb

@@ -0,0 +1,38 @@
+# SPDX-License-Identifier: LGPL-3.0-or-later */
+# Copyright (C) 2020 Intel Corporation
+#                    Michał Kowalczyk <mkow@invisiblethingslab.com>
+
+# Tell Graphene to behave more gdb-friendly.
+set env IN_GDB=1
+
+# Used internally by Graphene, generates a lot of noise if we don't silence it.
+handle SIGCONT pass noprint nostop
+
+# TODO: This block of commands was copied from an older Graphene integration script where they
+# didn't have any comments with rationale why they are needed. We should revise and comment them.
+set auto-load off
+handle SIGKILL pass print stop
+set disable-randomization off
+set detach-on-fork off
+set schedule-multiple on
+set follow-fork-mode child
+
+break pal_start
+command
+    silent
+    set scheduler-locking off
+    continue
+end
+
+break thread_start
+command
+    silent
+    continue
+end
+
+catch vfork
+command
+    silent
+    set scheduler-locking on
+    continue
+end

Pal/src/host/Linux/gdb_integration/graphene_gdb.py

@@ -0,0 +1,15 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: LGPL-3.0-or-later */
+# Copyright (C) 2020 Intel Corporation
+#                    Michał Kowalczyk <mkow@invisiblethingslab.com>
+
+import os
+import gdb  # pylint: disable=import-error
+
+def main():
+    gdb_script = os.path.dirname(__file__) + "/graphene.gdb"
+    print("[%s] Loading %s..." % (os.path.basename(__file__), gdb_script))
+    gdb.execute("source " + gdb_script)
+
+if __name__ == '__main__':
+    main()

Pal/src/host/Linux/pal-gdb.py

@@ -1,16 +0,0 @@
-#!/usr/bin/env python3
-
-import os, sys, gdb
-
-if len(gdb.inferiors()) == 1:
-    gdb.execute("set env IN_GDB = 1")
-    gdb.execute("set auto-load off")
-
-    sys.stdout.write("Are you loading the script [Y]/n ? ")
-    sys.stdout.flush()
-    ans = sys.stdin.readline()
-
-    if ans[0] != 'n' and ans[0] != 'N':
-        gdbfile = os.path.dirname(__file__) + "/pal.gdb"
-        gdb.execute("source " + gdbfile)
-        sys.stdout.write("script %s loaded\n" % gdbfile)

Pal/src/host/Linux/pal.gdb

@@ -1,27 +0,0 @@
-handle SIGCONT pass noprint nostop
-handle SIGKILL pass print stop
-
-set disable-randomization off
-set detach-on-fork off
-set schedule-multiple on
-set follow-fork-mode child
-
-break pal_start
-command
-    silent
-    set scheduler-locking off
-    continue
-end
-
-break thread_start
-command
-    silent
-    continue
-end
-
-catch vfork
-command
-    silent
-    set scheduler-locking on
-    continue
-end

Pal/src/host/Skeleton/Makefile.am

@@ -16,4 +16,3 @@ pal_lib = $(HOST_DIR)/libpal.so
 pal_lib_deps = pal-symbols $(HOST_DIR)/pal.map.template $(HOST_DIR)/pal-$(ARCH).lds
 pal_lib_post =
 pal_static =
-pal_gdb =

Runtime/.gitignore

@@ -1,3 +1,2 @@
 /pal-Linux
 /pal-Linux-SGX
-/pal_gdb-Linux-SGX

Runtime/Makefile

@@ -3,7 +3,7 @@ all:
 
 .PHONY: clean
 clean:
-	$(RM) *.a *.o *.so *.so.* pal_gdb* pal-*
+	$(RM) *.a *.o *.so *.so.* pal-*
 
 .PHONY: distclean
 distclean: clean

Runtime/pal_loader

@@ -1,4 +1,9 @@
 #!/usr/bin/env bash
+# SPDX-License-Identifier: LGPL-3.0-or-later */
+# Copyright (C) 2014 Stony Brook University
+# Copyright (C) 2019 Invisible Things Lab
+# Copyright (C) 2020 Intel Corporation
+#                    Michał Kowalczyk <mkow@invisiblethingslab.com>
 
 while :
 do
@@ -42,28 +47,22 @@ if [ -z "$PAL_HOST" ]; then
 fi
 
 MANIFEST=
+ENVS=()
 PREFIX=()
-PAL_CMD=$RUNTIME_DIR/pal-$PAL_HOST
+PAL_CMD="$RUNTIME_DIR/pal-$PAL_HOST"
 LIBPAL_PATH=$(realpath "$RUNTIME_DIR/libpal-$PAL_HOST.so")
+HOST_PAL_PATH=$(realpath "$RUNTIME_DIR/../Pal/src/host/$PAL_HOST")
 
 if [ "$GDB" == "1" ]; then
-	GDB=$RUNTIME_DIR/pal_gdb-$PAL_HOST
-	if [ ! -f "$GDB" ]; then
-		GDB="gdb"
-	fi
-fi
-
-if [ "$GDB" != "" ] && [ "$GDB" != "0" ]; then
-	PREFIX=("$GDB" -q)
+	PREFIX=("gdb" "-q")
 	if [ -n "$INSIDE_EMACS" ]; then
 		PREFIX+=("-i=mi")
 	fi
 	if [ -v SGX ]; then
-		PREFIX+=("-iex")
-		PREFIX+=("dir $RUNTIME_DIR/../Pal/src/host/Linux-SGX")
+		PREFIX+=("-x" "$HOST_PAL_PATH/gdb_integration/graphene_sgx_gdb.py")
+		ENVS+=("LD_PRELOAD=$HOST_PAL_PATH/gdb_integration/sgx_gdb.so")
 	else
-		PREFIX+=("-iex")
-		PREFIX+=("dir $RUNTIME_DIR/../Pal/src/host/Linux")
+		PREFIX+=("-x" "$HOST_PAL_PATH/gdb_integration/graphene_gdb.py")
 	fi
 	PREFIX+=("--args")
 fi
@@ -93,8 +92,7 @@ if [ ! -f "$PAL_CMD" ]; then
 	exit 1
 fi
 
-if [ ${#PREFIX[@]} -eq 0 ]; then
-    exec "$PAL_CMD" "$LIBPAL_PATH" init "$MANIFEST" "$@"
-else
-    exec "${PREFIX[@]}" "$PAL_CMD" "$LIBPAL_PATH" init "$MANIFEST" "$@"
-fi
+CMD=("${ENVS[@]}")
+CMD+=("${PREFIX[@]}")
+CMD+=("$PAL_CMD" "$LIBPAL_PATH" init "$MANIFEST" "$@")
+exec env "${CMD[@]}"

Tools/gsc/templates/Dockerfile.ubuntu18.04.build.template

@@ -47,8 +47,12 @@ COPY --from=graphene /graphene/Pal/src/host/Linux-SGX/signer/pal_sgx_sign.py /gr
 COPY --from=graphene /graphene/Pal/src/host/Linux-SGX/generated_offsets.py /graphene/signer/
 COPY --from=graphene /graphene/Tools/argv_serializer /graphene/Tools
 {% if debug %}
-COPY --from=graphene /graphene/Pal/src/host/Linux-SGX/debugger/sgx_gdb.so /graphene/Runtime
-COPY --from=graphene /graphene/Pal/src/host/Linux-SGX/debugger/pal-gdb.py /graphene/Runtime
+COPY --from=graphene /graphene/Pal/src/host/Linux-SGX/gdb_integration/sgx_gdb.so \
+                     /graphene/Pal/src/host/Linux-SGX/gdb_integration/
+COPY --from=graphene /graphene/Pal/src/host/Linux-SGX/gdb_integration/graphene_sgx_gdb.py \
+                     /graphene/Pal/src/host/Linux-SGX/gdb_integration/
+COPY --from=graphene /graphene/Pal/src/host/Linux-SGX/gdb_integration/graphene_sgx.gdb \
+                     /graphene/Pal/src/host/Linux-SGX/gdb_integration/
 {% endif %}
 
 # Copy template scripts and manifests