Enable exec_binary syscall test on Arm64

Signed-off-by: Bin Lu <bin.lu@arm.com>

2 files changed, 143 insertions, 26 deletions

diff --git a/test/syscalls/linux/BUILD b/test/syscalls/linux/BUILD
index d0c431234..9447b06a8 100644
--- a/test/syscalls/linux/BUILD
+++ b/test/syscalls/linux/BUILD
@@ -663,10 +663,7 @@ cc_binary(
 cc_binary(
     name = "exec_binary_test",
     testonly = 1,
-    srcs = select_arch(
-        amd64 = ["exec_binary.cc"],
-        arm64 = [],
-    ),
+    srcs = ["exec_binary.cc"],
     linkstatic = 1,
     deps = [
         "//test/util:cleanup",
diff --git a/test/syscalls/linux/exec_binary.cc b/test/syscalls/linux/exec_binary.cc
index 736452b0c..ae2683256 100644
--- a/test/syscalls/linux/exec_binary.cc
+++ b/test/syscalls/linux/exec_binary.cc
@@ -48,10 +48,17 @@ namespace {
 using ::testing::AnyOf;
 using ::testing::Eq;
 
-#ifndef __x86_64__
+#if !defined(__x86_64__) && !defined(__aarch64__)
 // The assembly stub and ELF internal details must be ported to other arches.
-#error "Test only supported on x86-64"
-#endif  // __x86_64__
+#error "Test only supported on x86-64/arm64"
+#endif  // __x86_64__ || __aarch64__
+
+#if defined(__x86_64__)
+#define EM_TYPE EM_X86_64
+#define IP_REG(p) ((p).rip)
+#define RAX_REG(p) ((p).rax)
+#define RDI_REG(p) ((p).rdi)
+#define RETURN_REG(p) ((p).rax)
 
 // amd64 stub that calls PTRACE_TRACEME and sends itself SIGSTOP.
 const char kPtraceCode[] = {
@@ -139,6 +146,76 @@ const char kPtraceCode[] = {
 // Size of a syscall instruction.
 constexpr int kSyscallSize = 2;
 
+#elif defined(__aarch64__)
+#define EM_TYPE EM_AARCH64
+#define IP_REG(p) ((p).pc)
+#define RAX_REG(p) ((p).regs[8])
+#define RDI_REG(p) ((p).regs[0])
+#define RETURN_REG(p) ((p).regs[0])
+
+const char kPtraceCode[] = {
+    // MOVD $117, R8 /* ptrace */
+    '\xa8',
+    '\x0e',
+    '\x80',
+    '\xd2',
+    // MOVD $0, R0 /* PTRACE_TRACEME */
+    '\x00',
+    '\x00',
+    '\x80',
+    '\xd2',
+    // MOVD $0, R1 /* pid */
+    '\x01',
+    '\x00',
+    '\x80',
+    '\xd2',
+    // MOVD $0, R2 /* addr */
+    '\x02',
+    '\x00',
+    '\x80',
+    '\xd2',
+    // MOVD $0, R3 /* data */
+    '\x03',
+    '\x00',
+    '\x80',
+    '\xd2',
+    // SVC
+    '\x01',
+    '\x00',
+    '\x00',
+    '\xd4',
+    // MOVD $172, R8 /* getpid */
+    '\x88',
+    '\x15',
+    '\x80',
+    '\xd2',
+    // SVC
+    '\x01',
+    '\x00',
+    '\x00',
+    '\xd4',
+    // MOVD $129, R8 /* kill, R0=pid */
+    '\x28',
+    '\x10',
+    '\x80',
+    '\xd2',
+    // MOVD $19, R1  /* SIGSTOP */
+    '\x61',
+    '\x02',
+    '\x80',
+    '\xd2',
+    // SVC
+    '\x01',
+    '\x00',
+    '\x00',
+    '\xd4',
+};
+// Size of a syscall instruction.
+constexpr int kSyscallSize = 4;
+#else
+#error "Unknown architecture"
+#endif
+
 // This test suite tests executable loading in the kernel (ELF and interpreter
 // scripts).
 
@@ -281,7 +358,7 @@ ElfBinary<64> StandardElf() {
   elf.header.e_ident[EI_DATA] = ELFDATA2LSB;
   elf.header.e_ident[EI_VERSION] = EV_CURRENT;
   elf.header.e_type = ET_EXEC;
-  elf.header.e_machine = EM_X86_64;
+  elf.header.e_machine = EM_TYPE;
   elf.header.e_version = EV_CURRENT;
   elf.header.e_phoff = sizeof(elf.header);
   elf.header.e_phentsize = sizeof(decltype(elf)::ElfPhdr);
@@ -327,9 +404,15 @@ TEST(ElfTest, Execute) {
   ASSERT_NO_ERRNO(WaitStopped(child));
 
   struct user_regs_struct regs;
-  ASSERT_THAT(ptrace(PTRACE_GETREGS, child, 0, &regs), SyscallSucceeds());
-  // RIP is just beyond the final syscall instruction.
-  EXPECT_EQ(regs.rip, elf.header.e_entry + sizeof(kPtraceCode));
+  struct iovec iov;
+  iov.iov_base = &regs;
+  iov.iov_len = sizeof(regs);
+  EXPECT_THAT(ptrace(PTRACE_GETREGSET, child, NT_PRSTATUS, &iov),
+              SyscallSucceeds());
+ // Read exactly the full register set.
+  EXPECT_EQ(iov.iov_len, sizeof(regs));
+  // RIP/PC is just beyond the final syscall instruction.
+  EXPECT_EQ(IP_REG(regs), elf.header.e_entry + sizeof(kPtraceCode));
 
   EXPECT_THAT(child, ContainsMappings(std::vector<ProcMapsEntry>({
                          {0x40000, 0x41000, true, false, true, true, 0, 0, 0, 0,
@@ -718,9 +801,16 @@ TEST(ElfTest, PIE) {
 
   // RIP tells us which page the first segment was loaded into.
   struct user_regs_struct regs;
-  ASSERT_THAT(ptrace(PTRACE_GETREGS, child, 0, &regs), SyscallSucceeds());
+  struct iovec iov;
+  iov.iov_base = &regs;
+  iov.iov_len = sizeof(regs);
 
-  const uint64_t load_addr = regs.rip & ~(kPageSize - 1);
+  EXPECT_THAT(ptrace(PTRACE_GETREGSET, child, NT_PRSTATUS, &iov),
+              SyscallSucceeds());
+  // Read exactly the full register set.
+  EXPECT_EQ(iov.iov_len, sizeof(regs));
+
+  const uint64_t load_addr = IP_REG(regs) & ~(kPageSize - 1);
 
   EXPECT_THAT(child, ContainsMappings(std::vector<ProcMapsEntry>({
                          // text page.
@@ -787,9 +877,15 @@ TEST(ElfTest, PIENonZeroStart) {
 
   // RIP tells us which page the first segment was loaded into.
   struct user_regs_struct regs;
-  ASSERT_THAT(ptrace(PTRACE_GETREGS, child, 0, &regs), SyscallSucceeds());
+  struct iovec iov;
+  iov.iov_base = &regs;
+  iov.iov_len = sizeof(regs);
+  EXPECT_THAT(ptrace(PTRACE_GETREGSET, child, NT_PRSTATUS, &iov),
+              SyscallSucceeds());
+  // Read exactly the full register set.
+  EXPECT_EQ(iov.iov_len, sizeof(regs));
 
-  const uint64_t load_addr = regs.rip & ~(kPageSize - 1);
+  const uint64_t load_addr = IP_REG(regs) & ~(kPageSize - 1);
 
   // The ELF is loaded at an arbitrary address, not the first PT_LOAD vaddr.
   //
@@ -910,9 +1006,15 @@ TEST(ElfTest, ELFInterpreter) {
   // RIP tells us which page the first segment of the interpreter was loaded
   // into.
   struct user_regs_struct regs;
-  ASSERT_THAT(ptrace(PTRACE_GETREGS, child, 0, &regs), SyscallSucceeds());
+  struct iovec iov;
+  iov.iov_base = &regs;
+  iov.iov_len = sizeof(regs);
+  EXPECT_THAT(ptrace(PTRACE_GETREGSET, child, NT_PRSTATUS, &iov),
+              SyscallSucceeds());
+  // Read exactly the full register set.
+  EXPECT_EQ(iov.iov_len, sizeof(regs));
 
-  const uint64_t interp_load_addr = regs.rip & ~(kPageSize - 1);
+  const uint64_t interp_load_addr = IP_REG(regs) & ~(kPageSize - 1);
 
   EXPECT_THAT(
       child, ContainsMappings(std::vector<ProcMapsEntry>({
@@ -1084,9 +1186,15 @@ TEST(ElfTest, ELFInterpreterRelative) {
   // RIP tells us which page the first segment of the interpreter was loaded
   // into.
   struct user_regs_struct regs;
-  ASSERT_THAT(ptrace(PTRACE_GETREGS, child, 0, &regs), SyscallSucceeds());
+  struct iovec iov;
+  iov.iov_base = &regs;
+  iov.iov_len = sizeof(regs);
+  EXPECT_THAT(ptrace(PTRACE_GETREGSET, child, NT_PRSTATUS, &iov),
+              SyscallSucceeds());
+  // Read exactly the full register set.
+  EXPECT_EQ(iov.iov_len, sizeof(regs));
 
-  const uint64_t interp_load_addr = regs.rip & ~(kPageSize - 1);
+  const uint64_t interp_load_addr = IP_REG(regs) & ~(kPageSize - 1);
 
   EXPECT_THAT(
       child, ContainsMappings(std::vector<ProcMapsEntry>({
@@ -1480,14 +1588,21 @@ TEST(ExecveTest, BrkAfterBinary) {
   ASSERT_NO_ERRNO(WaitStopped(child));
 
   struct user_regs_struct regs;
-  ASSERT_THAT(ptrace(PTRACE_GETREGS, child, 0, &regs), SyscallSucceeds());
+  struct iovec iov;
+  iov.iov_base = &regs;
+  iov.iov_len = sizeof(regs);
+  EXPECT_THAT(ptrace(PTRACE_GETREGSET, child, NT_PRSTATUS, &iov),
+    SyscallSucceeds());
+  // Read exactly the full register set.
+  EXPECT_EQ(iov.iov_len, sizeof(regs));
 
   // RIP is just beyond the final syscall instruction. Rewind to execute a brk
   // syscall.
-  regs.rip -= kSyscallSize;
-  regs.rax = __NR_brk;
-  regs.rdi = 0;
-  ASSERT_THAT(ptrace(PTRACE_SETREGS, child, 0, &regs), SyscallSucceeds());
+  IP_REG(regs) -= kSyscallSize;
+  RAX_REG(regs) = __NR_brk;
+  RDI_REG(regs) = 0;
+  ASSERT_THAT(ptrace(PTRACE_SETREGSET, child, NT_PRSTATUS, &iov),
+    SyscallSucceeds());
 
   // Resume the child, waiting for syscall entry.
   ASSERT_THAT(ptrace(PTRACE_SYSCALL, child, 0, 0), SyscallSucceeds());
@@ -1504,7 +1619,12 @@ TEST(ExecveTest, BrkAfterBinary) {
   ASSERT_TRUE(WIFSTOPPED(status) && WSTOPSIG(status) == SIGTRAP)
       << "status = " << status;
 
-  ASSERT_THAT(ptrace(PTRACE_GETREGS, child, 0, &regs), SyscallSucceeds());
+  iov.iov_base = &regs;
+  iov.iov_len = sizeof(regs);
+  EXPECT_THAT(ptrace(PTRACE_GETREGSET, child, NT_PRSTATUS, &iov),
+    SyscallSucceeds());
+  //Read exactly the full register set.
+  EXPECT_EQ(iov.iov_len, sizeof(regs));
 
   // brk is after the text page.
   //
@@ -1512,7 +1632,7 @@ TEST(ExecveTest, BrkAfterBinary) {
   // address will be, but it is always beyond the final page in the binary.
   // i.e., it does not start immediately after memsz in the middle of a page.
   // Userspace may expect to use that space.
-  EXPECT_GE(regs.rax, 0x41000);
+  EXPECT_GE(RETURN_REG(regs), 0x41000);
 }
 
 }  // namespace