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-rw-r--r--test/syscalls/linux/32bit.cc226
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diff --git a/test/syscalls/linux/32bit.cc b/test/syscalls/linux/32bit.cc
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index a7cbee06b..000000000
--- a/test/syscalls/linux/32bit.cc
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@@ -1,226 +0,0 @@
-// Copyright 2018 The gVisor Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#include <string.h>
-#include <sys/mman.h>
-
-#include "test/util/memory_util.h"
-#include "test/util/posix_error.h"
-#include "test/util/test_util.h"
-#include "gtest/gtest.h"
-
-#ifndef __x86_64__
-#error "This test is x86-64 specific."
-#endif
-
-namespace gvisor {
-namespace testing {
-
-namespace {
-
-constexpr char kInt3 = '\xcc';
-
-constexpr char kInt80[2] = {'\xcd', '\x80'};
-constexpr char kSyscall[2] = {'\x0f', '\x05'};
-constexpr char kSysenter[2] = {'\x0f', '\x34'};
-
-void ExitGroup32(const char instruction[2], int code) {
- const Mapping m = ASSERT_NO_ERRNO_AND_VALUE(
- Mmap(nullptr, kPageSize, PROT_READ | PROT_WRITE | PROT_EXEC,
- MAP_PRIVATE | MAP_ANONYMOUS | MAP_32BIT, -1, 0));
-
- // Fill with INT 3 in case we execute too far.
- memset(m.ptr(), kInt3, m.len());
-
- memcpy(m.ptr(), instruction, 2);
-
- // We're playing *extremely* fast-and-loose with the various syscall ABIs
- // here, which we can more-or-less get away with since exit_group doesn't
- // return.
- //
- // SYSENTER expects the user stack in (%ebp) and arg6 in 0(%ebp). The kernel
- // will unconditionally dereference %ebp for arg6, so we must pass a valid
- // address or it will return EFAULT.
- //
- // SYSENTER also unconditionally returns to thread_info->sysenter_return which
- // is ostensibly a stub in the 32-bit VDSO. But a 64-bit binary doesn't have
- // the 32-bit VDSO mapped, so sysenter_return will simply be the value
- // inherited from the most recent 32-bit ancestor, or NULL if there is none.
- // As a result, return would not return from SYSENTER.
- asm volatile(
- "movl $252, %%eax\n" // exit_group
- "movl %[code], %%ebx\n" // code
- "movl %%edx, %%ebp\n" // SYSENTER: user stack (use IP as a valid addr)
- "leaq -20(%%rsp), %%rsp\n"
- "movl $0x2b, 16(%%rsp)\n" // SS = CPL3 data segment
- "movl $0,12(%%rsp)\n" // ESP = nullptr (unused)
- "movl $0, 8(%%rsp)\n" // EFLAGS
- "movl $0x23, 4(%%rsp)\n" // CS = CPL3 32-bit code segment
- "movl %%edx, 0(%%rsp)\n" // EIP
- "iretl\n"
- "int $3\n"
- :
- : [code] "m"(code), [ip] "d"(m.ptr())
- : "rax", "rbx", "rsp");
-}
-
-constexpr int kExitCode = 42;
-
-TEST(Syscall32Bit, Int80) {
- switch (GvisorPlatform()) {
- case Platform::kKVM:
- // TODO(b/111805002): 32-bit segments are broken (but not explictly
- // disabled).
- return;
- case Platform::kPtrace:
- // TODO(gvisor.dev/issue/167): The ptrace platform does not have a
- // consistent story here.
- return;
- case Platform::kNative:
- break;
- }
-
- // Upstream Linux. 32-bit syscalls allowed.
- EXPECT_EXIT(ExitGroup32(kInt80, kExitCode), ::testing::ExitedWithCode(42),
- "");
-}
-
-TEST(Syscall32Bit, Sysenter) {
- switch (GvisorPlatform()) {
- case Platform::kKVM:
- // TODO(b/111805002): See above.
- return;
- case Platform::kPtrace:
- // TODO(gvisor.dev/issue/167): See above.
- return;
- case Platform::kNative:
- break;
- }
-
- if (GetCPUVendor() == CPUVendor::kAMD) {
- // SYSENTER is an illegal instruction in compatibility mode on AMD.
- EXPECT_EXIT(ExitGroup32(kSysenter, kExitCode),
- ::testing::KilledBySignal(SIGILL), "");
- return;
- }
-
- // Upstream Linux on !AMD, 32-bit syscalls allowed.
- EXPECT_EXIT(ExitGroup32(kSysenter, kExitCode), ::testing::ExitedWithCode(42),
- "");
-}
-
-TEST(Syscall32Bit, Syscall) {
- switch (GvisorPlatform()) {
- case Platform::kKVM:
- // TODO(b/111805002): See above.
- return;
- case Platform::kPtrace:
- // TODO(gvisor.dev/issue/167): See above.
- return;
- case Platform::kNative:
- break;
- }
-
- if (GetCPUVendor() == CPUVendor::kIntel) {
- // SYSCALL is an illegal instruction in compatibility mode on Intel.
- EXPECT_EXIT(ExitGroup32(kSyscall, kExitCode),
- ::testing::KilledBySignal(SIGILL), "");
- return;
- }
-
- // Upstream Linux on !Intel, 32-bit syscalls allowed.
- EXPECT_EXIT(ExitGroup32(kSyscall, kExitCode), ::testing::ExitedWithCode(42),
- "");
-}
-
-// Far call code called below.
-//
-// Input stack layout:
-//
-// %esp+12 lcall segment
-// %esp+8 lcall address offset
-// %esp+0 return address
-//
-// The lcall will enter compatibility mode and jump to the call address (the
-// address of the lret). The lret will return to 64-bit mode at the retq, which
-// will return to the external caller of this function.
-//
-// Since this enters compatibility mode, it must be mapped in a 32-bit region of
-// address space and have a 32-bit stack pointer.
-constexpr char kFarCall[] = {
- '\x67', '\xff', '\x5c', '\x24', '\x08', // lcall *8(%esp)
- '\xc3', // retq
- '\xcb', // lret
-};
-
-void FarCall32() {
- const Mapping m = ASSERT_NO_ERRNO_AND_VALUE(
- Mmap(nullptr, kPageSize, PROT_READ | PROT_WRITE | PROT_EXEC,
- MAP_PRIVATE | MAP_ANONYMOUS | MAP_32BIT, -1, 0));
-
- // Fill with INT 3 in case we execute too far.
- memset(m.ptr(), kInt3, m.len());
-
- // 32-bit code.
- memcpy(m.ptr(), kFarCall, sizeof(kFarCall));
-
- // Use the end of the code page as its stack.
- uintptr_t stack = m.endaddr();
-
- uintptr_t lcall = m.addr();
- uintptr_t lret = m.addr() + sizeof(kFarCall) - 1;
-
- // N.B. We must save and restore RSP manually. GCC can do so automatically
- // with an "rsp" clobber, but clang cannot.
- asm volatile(
- // Place the address of lret (%edx) and the 32-bit code segment (0x23) on
- // the 32-bit stack for lcall.
- "subl $0x8, %%ecx\n"
- "movl $0x23, 4(%%ecx)\n"
- "movl %%edx, 0(%%ecx)\n"
-
- // Save the current stack and switch to 32-bit stack.
- "pushq %%rbp\n"
- "movq %%rsp, %%rbp\n"
- "movq %%rcx, %%rsp\n"
-
- // Run the lcall code.
- "callq *%%rbx\n"
-
- // Restore the old stack.
- "leaveq\n"
- : "+c"(stack)
- : "b"(lcall), "d"(lret));
-}
-
-TEST(Call32Bit, Disallowed) {
- switch (GvisorPlatform()) {
- case Platform::kKVM:
- // TODO(b/111805002): See above.
- return;
- case Platform::kPtrace:
- // The ptrace platform cannot prevent switching to compatibility mode.
- ABSL_FALLTHROUGH_INTENDED;
- case Platform::kNative:
- break;
- }
-
- // Shouldn't crash.
- FarCall32();
-}
-
-} // namespace
-
-} // namespace testing
-} // namespace gvisor
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-01 18:29:33 +0000