[Lldb-commits] [lldb] 53430bf - Remove hardcoded address bits in ABIMacOS_arm64
Jason Molenda via lldb-commits
lldb-commits at lists.llvm.org
Tue Apr 18 13:27:32 PDT 2023
Author: Jason Molenda
Date: 2023-04-18T13:01:49-07:00
New Revision: 53430bfd5c9d0074dd6de06dccea366e1d40bce4
URL: https://github.com/llvm/llvm-project/commit/53430bfd5c9d0074dd6de06dccea366e1d40bce4
DIFF: https://github.com/llvm/llvm-project/commit/53430bfd5c9d0074dd6de06dccea366e1d40bce4.diff
LOG: Remove hardcoded address bits in ABIMacOS_arm64
A default number of addressing bits was hardcoded in
ABIMacOSX_arm64::FixAddress while we updated different
environments to fetch the value dynamically. Remove
the old hardcoded value.
Differential Revision: https://reviews.llvm.org/D148603
rdar://108068497
Added:
Modified:
lldb/source/Plugins/ABI/AArch64/ABIMacOSX_arm64.cpp
Removed:
lldb/test/API/macosx/corefile-default-ptrauth/Makefile
lldb/test/API/macosx/corefile-default-ptrauth/TestCorefileDefaultPtrauth.py
lldb/test/API/macosx/corefile-default-ptrauth/create-corefile.c
lldb/test/API/macosx/corefile-default-ptrauth/main.c
################################################################################
diff --git a/lldb/source/Plugins/ABI/AArch64/ABIMacOSX_arm64.cpp b/lldb/source/Plugins/ABI/AArch64/ABIMacOSX_arm64.cpp
index 4079338e190cd..4d2505ece50de 100644
--- a/lldb/source/Plugins/ABI/AArch64/ABIMacOSX_arm64.cpp
+++ b/lldb/source/Plugins/ABI/AArch64/ABIMacOSX_arm64.cpp
@@ -816,15 +816,12 @@ ValueObjectSP ABIMacOSX_arm64::GetReturnValueObjectImpl(
lldb::addr_t ABIMacOSX_arm64::FixAddress(addr_t pc, addr_t mask) {
lldb::addr_t pac_sign_extension = 0x0080000000000000ULL;
- // Darwin systems originally couldn't determine the proper value
- // dynamically, so the most common value was hardcoded. This has
- // largely been cleaned up, but there are still a handful of
- // environments that assume the default value is set to this value
- // and there's no dynamic value to correct it.
- // When no mask is specified, set it to 39 bits of addressing (0..38).
+ // When no mask is specified, clear/set the top byte; preserve
+ // the low 55 bits (00..54) for addressing and bit 55 to indicate
+ // sign.
if (mask == 0) {
- // ~((1ULL<<39)-1)
- mask = 0xffffff8000000000;
+ // ~((1ULL<<55)-1)
+ mask = 0xff80000000000000;
}
return (pc & pac_sign_extension) ? pc | mask : pc & (~mask);
}
diff --git a/lldb/test/API/macosx/corefile-default-ptrauth/Makefile b/lldb/test/API/macosx/corefile-default-ptrauth/Makefile
deleted file mode 100644
index 2ec01bc411528..0000000000000
--- a/lldb/test/API/macosx/corefile-default-ptrauth/Makefile
+++ /dev/null
@@ -1,12 +0,0 @@
-C_SOURCES := main.c
-
-# compile a.out and create-corefile
-# create-corefile will create a custom corefile using the symbols
-# addresses from the a.out binary.
-all: a.out create-corefile
-
-create-corefile:
- $(MAKE) -f $(MAKEFILE_RULES) EXE=create-corefile \
- C_SOURCES=create-corefile.c
-
-include Makefile.rules
diff --git a/lldb/test/API/macosx/corefile-default-ptrauth/TestCorefileDefaultPtrauth.py b/lldb/test/API/macosx/corefile-default-ptrauth/TestCorefileDefaultPtrauth.py
deleted file mode 100644
index f9a62bc2b6778..0000000000000
--- a/lldb/test/API/macosx/corefile-default-ptrauth/TestCorefileDefaultPtrauth.py
+++ /dev/null
@@ -1,51 +0,0 @@
-"""Test that lldb has a default mask for addressable bits on Darwin arm64 ABI"""
-
-
-import os
-import re
-import subprocess
-
-import lldb
-from lldbsuite.test.decorators import *
-from lldbsuite.test.lldbtest import *
-from lldbsuite.test import lldbutil
-
-
-class TestCorefileDefaultPtrauth(TestBase):
-
- @skipIf(debug_info=no_match(["dsym"]), bugnumber="This test is looking explicitly for a dSYM")
- @skipIf(archs=no_match(['arm64','arm64e']))
- @skipUnlessDarwin
- @skipIfRemote
- def test_lc_note(self):
- self.build()
- self.test_exe = self.getBuildArtifact("a.out")
- self.create_corefile = self.getBuildArtifact("create-corefile")
- self.corefile = self.getBuildArtifact("core")
-
- ### Create our corefile
- retcode = call(self.create_corefile + " " + self.test_exe + " " + self.corefile, shell=True)
-
- ## This corefile has no metadata telling us how many bits are
- ## used for ptrauth signed function pointers. We will need lldb
- ## to fall back on its old default value for Darwin arm64 ABIs
- ## to correctly strip the bits.
-
- # Create a Target with our main executable binary to get it
- # seeded in lldb's global module cache. Then delete the Target.
- # This way when the corefile searches for a binary with its UUID,
- # it'll be found by that search.
- initial_target = self.dbg.CreateTarget(self.test_exe)
- self.dbg.DeleteTarget(initial_target)
-
- self.target = self.dbg.CreateTarget('')
- err = lldb.SBError()
- self.process = self.target.LoadCore(self.corefile)
- self.assertEqual(self.process.IsValid(), True)
-
- # target variable should show us both the actual function
- # pointer with ptrauth bits and the symbol it resolves to,
- # with the ptrauth bits stripped, e.g.
- # (int (*)(...)) fmain = 0xe46bff0100003f90 (actual=0x0000000100003f90 a.out`main at main.c:3)
-
- self.expect("target variable fmain", substrs=['fmain = 0x', '(actual=0x', 'main at main.c'])
diff --git a/lldb/test/API/macosx/corefile-default-ptrauth/create-corefile.c b/lldb/test/API/macosx/corefile-default-ptrauth/create-corefile.c
deleted file mode 100644
index e5168089b87d2..0000000000000
--- a/lldb/test/API/macosx/corefile-default-ptrauth/create-corefile.c
+++ /dev/null
@@ -1,189 +0,0 @@
-#include <mach-o/loader.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <mach/machine.h>
-#include <string.h>
-#include <mach/machine/thread_state.h>
-#include <inttypes.h>
-#include <sys/syslimits.h>
-#include <uuid/uuid.h>
-
-// Given an executable binary with
-// "fmain" (a function pointer to main)
-// "main"
-// symbols, create a fake arm64e corefile that
-// contains a memory segment for the fmain
-// function pointer, with the value of the
-// address of main() with ptrauth bits masked on.
-//
-// The corefile does not include the "addrable bits"
-// LC_NOTE, so lldb will need to fall back on its
-// default value from the Darwin arm64 ABI.
-
-int main(int argc, char **argv)
-{
- if (argc != 3) {
- fprintf (stderr, "usage: %s executable-binary output-file\n", argv[0]);
- exit(1);
- }
- FILE *exe = fopen(argv[1], "r");
- if (!exe) {
- fprintf (stderr, "Unable to open executable %s for reading\n", argv[1]);
- exit(1);
- }
- FILE *out = fopen(argv[2], "w");
- if (!out) {
- fprintf (stderr, "Unable to open %s for writing\n", argv[2]);
- exit(1);
- }
-
- char buf[PATH_MAX + 6];
- sprintf (buf, "nm '%s'", argv[1]);
- FILE *nm = popen(buf, "r");
- if (!nm) {
- fprintf (stderr, "Unable to run nm on '%s'", argv[1]);
- exit (1);
- }
- uint64_t main_addr = 0;
- uint64_t fmain_addr = 0;
- while (fgets (buf, sizeof(buf), nm)) {
- if (strstr (buf, "_fmain")) {
- fmain_addr = strtoul (buf, NULL, 16);
- }
- if (strstr (buf, "_main")) {
- main_addr = strtoul (buf, NULL, 16);
- }
- }
- pclose (nm);
-
- sprintf (buf, "dwarfdump -u '%s'", argv[1]);
- FILE *dwarfdump = popen(buf, "r");
- if (!dwarfdump) {
- fprintf (stderr, "Unable to run dwarfdump -u on '%s'\n", argv[1]);
- exit (1);
- }
- uuid_t uuid;
- uuid_clear (uuid);
- while (fgets (buf, sizeof(buf), dwarfdump)) {
- if (strncmp (buf, "UUID: ", 6) == 0) {
- buf[6 + 36] = '\0';
- if (uuid_parse (buf + 6, uuid) != 0) {
- fprintf (stderr, "Unable to parse UUID in '%s'\n", buf);
- exit (1);
- }
- }
- }
- if (uuid_is_null(uuid)) {
- fprintf (stderr, "Got a null uuid for the binary\n");
- exit (1);
- }
-
- if (main_addr == 0 || fmain_addr == 0) {
- fprintf(stderr, "Unable to find address of main or fmain in %s.\n",
- argv[1]);
- exit (1);
- }
-
- // Write out a corefile with contents in this order:
- // 1. mach header
- // 2. LC_THREAD load command
- // 3. LC_SEGMENT_64 load command
- // 4. LC_NOTE load command
- // 5. memory segment contents
- // 6. "load binary" note contents
-
- // struct thread_command {
- // uint32_t cmd;
- // uint32_t cmdsize;
- // uint32_t flavor
- // uint32_t count
- // struct XXX_thread_state state
- int size_of_thread_cmd = 4 + 4 + 4 + 4 + sizeof (arm_thread_state64_t);
-
- struct mach_header_64 mh;
- mh.magic = 0xfeedfacf;
- mh.cputype = CPU_TYPE_ARM64;
- mh.cpusubtype = CPU_SUBTYPE_ARM64E;
- mh.filetype = MH_CORE;
- mh.ncmds = 3; // LC_THREAD, LC_SEGMENT_64, LC_NOTE
- mh.sizeofcmds = size_of_thread_cmd + sizeof(struct segment_command_64) + sizeof(struct note_command);
- mh.flags = 0;
- mh.reserved = 0;
-
- fwrite(&mh, sizeof (mh), 1, out);
-
- struct note_command lcnote;
- struct segment_command_64 seg;
- seg.cmd = LC_SEGMENT_64;
- seg.cmdsize = sizeof(seg);
- memset (&seg.segname, 0, 16);
- seg.vmaddr = fmain_addr;
- seg.vmsize = 8;
- // Offset to segment contents
- seg.fileoff = sizeof (mh) + size_of_thread_cmd + sizeof(seg) + sizeof(lcnote);
- seg.filesize = 8;
- seg.maxprot = 3;
- seg.initprot = 3;
- seg.nsects = 0;
- seg.flags = 0;
-
- fwrite (&seg, sizeof (seg), 1, out);
-
- uint32_t cmd = LC_THREAD;
- fwrite (&cmd, sizeof (cmd), 1, out);
- uint32_t cmdsize = size_of_thread_cmd;
- fwrite (&cmdsize, sizeof (cmdsize), 1, out);
- uint32_t flavor = ARM_THREAD_STATE64;
- fwrite (&flavor, sizeof (flavor), 1, out);
- // count is number of uint32_t's of the register context
- uint32_t count = sizeof (arm_thread_state64_t) / 4;
- fwrite (&count, sizeof (count), 1, out);
- arm_thread_state64_t regstate;
- memset (®state, 0, sizeof (regstate));
- fwrite (®state, sizeof (regstate), 1, out);
-
- lcnote.cmd = LC_NOTE;
- lcnote.cmdsize = sizeof (lcnote);
- strcpy (lcnote.data_owner, "load binary");
-
- // 8 is the size of the LC_SEGMENT contents
- lcnote.offset = sizeof (mh) + size_of_thread_cmd + sizeof(seg) + sizeof(lcnote) + 8;
-
- // struct load_binary
- // {
- // uint32_t version; // currently 1
- // uuid_t uuid; // all zeroes if uuid not specified
- // uint64_t load_address; // virtual address where the macho is loaded, UINT64_MAX if unavail
- // uint64_t slide; // slide to be applied to file address to get load address, 0 if unavail
- // char name_cstring[]; // must be nul-byte terminated c-string, '\0' alone if name unavail
- // } __attribute__((packed));
- lcnote.size = 4 + 16 + 8 + 8 + sizeof("a.out");
-
- fwrite (&lcnote, sizeof(lcnote), 1, out);
-
- // Write the contents of the memory segment
-
- // Or together a random PAC value from a system using 39 bits
- // of addressing with the address of main(). lldb will need
- // to correctly strip off the high bits to find the address of
- // main.
- uint64_t segment_contents = 0xe46bff0000000000 | main_addr;
- fwrite (&segment_contents, sizeof (segment_contents), 1, out);
-
- // Now write the contents of the "load binary" LC_NOTE.
- {
- uint32_t version = 1;
- fwrite (&version, sizeof (version), 1, out);
- fwrite (&uuid, sizeof (uuid), 1, out);
- uint64_t load_address = UINT64_MAX;
- fwrite (&load_address, sizeof (load_address), 1, out);
- uint64_t slide = 0;
- fwrite (&slide, sizeof (slide), 1, out);
- strcpy (buf, "a.out");
- fwrite (buf, 6, 1, out);
- }
-
- fclose (out);
-
- exit (0);
-}
diff --git a/lldb/test/API/macosx/corefile-default-ptrauth/main.c b/lldb/test/API/macosx/corefile-default-ptrauth/main.c
deleted file mode 100644
index d37310982b1dd..0000000000000
--- a/lldb/test/API/macosx/corefile-default-ptrauth/main.c
+++ /dev/null
@@ -1,6 +0,0 @@
-int main();
-int (*fmain)() = main;
-int main () {
- return fmain();
-}
-
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