From: Elliott Hughes Date: Wed, 29 Mar 2017 20:48:02 +0000 (-0700) Subject: Fix x86 system calls made from ELF preinit. X-Git-Tag: android-x86-8.1-r1~52^2^2~27 X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=842423911f;p=android-x86%2Fbionic.git Fix x86 system calls made from ELF preinit. Used by CFI, so broke cfi_test#early_init@x86, but I've added a specific test for this (and a similar test for getauxval from preinit, which this patch does not fix). Bug: http://b/35885875 Test: ran tests (cherry picked from commit eb04ed506fbb0561b677d9518c9bae33f0262b03) Change-Id: Ie9da1bf4c2dcc23be7d75c739ae8549309813f88 --- diff --git a/libc/bionic/libc_init_common.cpp b/libc/bionic/libc_init_common.cpp index e5654c3f6..9094fc5b7 100644 --- a/libc/bionic/libc_init_common.cpp +++ b/libc/bionic/libc_init_common.cpp @@ -62,7 +62,11 @@ const char* __progname; char** environ; #if defined(__i386__) -__LIBC_HIDDEN__ void* __libc_sysinfo = nullptr; +__attribute__((__naked__)) static void __libc_int0x80() { + __asm__ volatile("int $0x80; ret"); +} + +__LIBC_HIDDEN__ void* __libc_sysinfo = reinterpret_cast(__libc_int0x80); __LIBC_HIDDEN__ void __libc_init_sysinfo(KernelArgumentBlock& args) { __libc_sysinfo = reinterpret_cast(args.getauxval(AT_SYSINFO)); diff --git a/tests/dl_test.cpp b/tests/dl_test.cpp index ee9b2e1d9..aa8bd5740 100644 --- a/tests/dl_test.cpp +++ b/tests/dl_test.cpp @@ -24,6 +24,7 @@ #include +#include "gtest_globals.h" #include "utils.h" extern "C" int main_global_default_serial() { @@ -86,4 +87,26 @@ TEST(dl, exec_linker) { #endif } +TEST(dl, preinit_system_calls) { +#if defined(__BIONIC__) + std::string helper = get_testlib_root() + + "/preinit_syscall_test_helper/preinit_syscall_test_helper"; + chmod(helper.c_str(), 0755); // TODO: "x" lost in CTS, b/34945607 + ExecTestHelper eth; + eth.SetArgs({ helper.c_str(), nullptr }); + eth.Run([&]() { execve(helper.c_str(), eth.GetArgs(), eth.GetEnv()); }, 0, nullptr); +#endif +} + +TEST(dl, xfail_preinit_getauxval) { +#if defined(__BIONIC__) + std::string helper = get_testlib_root() + + "/preinit_getauxval_test_helper/preinit_getauxval_test_helper"; + chmod(helper.c_str(), 0755); // TODO: "x" lost in CTS, b/34945607 + ExecTestHelper eth; + eth.SetArgs({ helper.c_str(), nullptr }); + eth.Run([&]() { execve(helper.c_str(), eth.GetArgs(), eth.GetEnv()); }, 0, nullptr); +#endif +} + // TODO: Add tests for LD_PRELOADs diff --git a/tests/libs/Android.bp b/tests/libs/Android.bp index 5eb16c52b..a031fe9ee 100644 --- a/tests/libs/Android.bp +++ b/tests/libs/Android.bp @@ -547,3 +547,17 @@ cc_test { shared_libs: ["libcfi-test"], ldflags: ["-Wl,--rpath,${ORIGIN}/.."], } + +cc_test { + name: "preinit_getauxval_test_helper", + host_supported: false, + defaults: ["bionic_testlib_defaults"], + srcs: ["preinit_getauxval_test_helper.cpp"], +} + +cc_test { + name: "preinit_syscall_test_helper", + host_supported: false, + defaults: ["bionic_testlib_defaults"], + srcs: ["preinit_syscall_test_helper.cpp"], +} diff --git a/tests/libs/libs_utils.h b/tests/libs/libs_utils.h index f11cbe782..7dae2414d 100644 --- a/tests/libs/libs_utils.h +++ b/tests/libs/libs_utils.h @@ -17,13 +17,11 @@ #ifndef LIBS_UTILS_H #define LIBS_UTILS_H +#include #include #include -#define CHECK(x) \ - do { \ - fprintf(stderr, "CHECK(" #x ") failed at %s:%d\n", __FILE__, __LINE__); \ - if (!(x)) abort(); \ - } while (0) +#define CHECK(e) \ + ((e) ? static_cast(0) : __assert2(__FILE__, __LINE__, __PRETTY_FUNCTION__, #e)) #endif // LIBS_UTILS_H diff --git a/tests/libs/preinit_getauxval_test_helper.cpp b/tests/libs/preinit_getauxval_test_helper.cpp new file mode 100644 index 000000000..2a79b97a1 --- /dev/null +++ b/tests/libs/preinit_getauxval_test_helper.cpp @@ -0,0 +1,39 @@ +/* + * Copyright (C) 2017 The Android Open Source Project + * + * 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 +#include +#include +#include + +#include "libs_utils.h" + +static unsigned long g_AT_RANDOM; +static unsigned long g_AT_PAGESZ; + +static void preinit_ctor() { + g_AT_RANDOM = getauxval(AT_RANDOM); + g_AT_PAGESZ = getauxval(AT_PAGESZ); +} + +__attribute__((section(".preinit_array"), used)) void (*preinit_ctor_p)(void) = preinit_ctor; + +int main() { + // Did getauxval during preinit get the same results as getauxval now? + CHECK(getauxval(AT_RANDOM) == g_AT_RANDOM); + CHECK(getauxval(AT_PAGESZ) == g_AT_PAGESZ); + return 0; +} diff --git a/tests/libs/preinit_syscall_test_helper.cpp b/tests/libs/preinit_syscall_test_helper.cpp new file mode 100644 index 000000000..9b6b6dfc4 --- /dev/null +++ b/tests/libs/preinit_syscall_test_helper.cpp @@ -0,0 +1,40 @@ +/* + * Copyright (C) 2017 The Android Open Source Project + * + * 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 +#include +#include +#include + +#include "libs_utils.h" + +static ssize_t g_result; +static int g_errno; + +static void preinit_ctor() { + // Can we make a system call? + g_result = write(-1, "", 1); + g_errno = errno; +} + +__attribute__((section(".preinit_array"), used)) void (*preinit_ctor_p)(void) = preinit_ctor; + +int main() { + // Did we get the expected failure? + CHECK(g_result == -1); + CHECK(g_errno == EBADF); + return 0; +}