| // Copyright 2017 The Crashpad Authors. All rights reserved. |
| // |
| // 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 "util/linux/scoped_ptrace_attach.h" |
| |
| #include <errno.h> |
| #include <sys/ptrace.h> |
| #include <unistd.h> |
| |
| #include "gtest/gtest.h" |
| #include "test/errors.h" |
| #include "test/multiprocess.h" |
| #include "util/file/file_io.h" |
| #include "util/linux/scoped_pr_set_ptracer.h" |
| |
| namespace crashpad { |
| namespace test { |
| namespace { |
| |
| // If Yama is not enabled, the default ptrace restrictions should be |
| // sufficient for these tests. |
| // |
| // If Yama is enabled, then /proc/sys/kernel/yama/ptrace_scope must be 0 |
| // (YAMA_SCOPE_DISABLED) or 1 (YAMA_SCOPE_RELATIONAL) for these tests to |
| // succeed. If it is 2 (YAMA_SCOPE_CAPABILITY) then the test requires |
| // CAP_SYS_PTRACE, and if it is 3 (YAMA_SCOPE_NO_ATTACH), these tests will fail. |
| |
| class AttachTest : public Multiprocess { |
| public: |
| AttachTest() : Multiprocess() {} |
| ~AttachTest() {} |
| |
| protected: |
| const long kWord = 42; |
| |
| private: |
| DISALLOW_COPY_AND_ASSIGN(AttachTest); |
| }; |
| |
| class AttachToChildTest : public AttachTest { |
| public: |
| AttachToChildTest() : AttachTest() {} |
| ~AttachToChildTest() {} |
| |
| private: |
| void MultiprocessParent() override { |
| // Wait for the child to set the parent as its ptracer. |
| char c; |
| CheckedReadFileExactly(ReadPipeHandle(), &c, sizeof(c)); |
| |
| pid_t pid = ChildPID(); |
| |
| ASSERT_EQ(ptrace(PTRACE_PEEKDATA, pid, &kWord, nullptr), -1); |
| EXPECT_EQ(errno, ESRCH) << ErrnoMessage("ptrace"); |
| |
| ScopedPtraceAttach attachment; |
| ASSERT_EQ(attachment.ResetAttach(pid), true); |
| EXPECT_EQ(ptrace(PTRACE_PEEKDATA, pid, &kWord, nullptr), kWord) |
| << ErrnoMessage("ptrace"); |
| attachment.Reset(); |
| |
| ASSERT_EQ(ptrace(PTRACE_PEEKDATA, pid, &kWord, nullptr), -1); |
| EXPECT_EQ(errno, ESRCH) << ErrnoMessage("ptrace"); |
| } |
| |
| void MultiprocessChild() override { |
| ScopedPrSetPtracer set_ptracer(getppid(), /* may_log= */ true); |
| |
| char c = '\0'; |
| CheckedWriteFile(WritePipeHandle(), &c, sizeof(c)); |
| |
| CheckedReadFileAtEOF(ReadPipeHandle()); |
| } |
| |
| DISALLOW_COPY_AND_ASSIGN(AttachToChildTest); |
| }; |
| |
| TEST(ScopedPtraceAttach, AttachChild) { |
| AttachToChildTest test; |
| test.Run(); |
| } |
| |
| class AttachToParentResetTest : public AttachTest { |
| public: |
| AttachToParentResetTest() : AttachTest() {} |
| ~AttachToParentResetTest() {} |
| |
| private: |
| void MultiprocessParent() override { |
| ScopedPrSetPtracer set_ptracer(ChildPID(), /* may_log= */ true); |
| char c = '\0'; |
| CheckedWriteFile(WritePipeHandle(), &c, sizeof(c)); |
| |
| CheckedReadFileAtEOF(ReadPipeHandle()); |
| } |
| |
| void MultiprocessChild() override { |
| // Wait for the parent to set the child as its ptracer. |
| char c; |
| CheckedReadFileExactly(ReadPipeHandle(), &c, sizeof(c)); |
| |
| pid_t pid = getppid(); |
| |
| ASSERT_EQ(ptrace(PTRACE_PEEKDATA, pid, &kWord, nullptr), -1); |
| EXPECT_EQ(errno, ESRCH) << ErrnoMessage("ptrace"); |
| |
| ScopedPtraceAttach attachment; |
| ASSERT_EQ(attachment.ResetAttach(pid), true); |
| EXPECT_EQ(ptrace(PTRACE_PEEKDATA, pid, &kWord, nullptr), kWord) |
| << ErrnoMessage("ptrace"); |
| attachment.Reset(); |
| |
| ASSERT_EQ(ptrace(PTRACE_PEEKDATA, pid, &kWord, nullptr), -1); |
| EXPECT_EQ(errno, ESRCH) << ErrnoMessage("ptrace"); |
| } |
| |
| DISALLOW_COPY_AND_ASSIGN(AttachToParentResetTest); |
| }; |
| |
| TEST(ScopedPtraceAttach, AttachParentReset) { |
| AttachToParentResetTest test; |
| test.Run(); |
| } |
| |
| class AttachToParentDestructorTest : public AttachTest { |
| public: |
| AttachToParentDestructorTest() : AttachTest() {} |
| ~AttachToParentDestructorTest() {} |
| |
| private: |
| void MultiprocessParent() override { |
| ScopedPrSetPtracer set_ptracer(ChildPID(), /* may_log= */ true); |
| char c = '\0'; |
| CheckedWriteFile(WritePipeHandle(), &c, sizeof(c)); |
| |
| CheckedReadFileAtEOF(ReadPipeHandle()); |
| } |
| |
| void MultiprocessChild() override { |
| // Wait for the parent to set the child as its ptracer. |
| char c; |
| CheckedReadFileExactly(ReadPipeHandle(), &c, sizeof(c)); |
| |
| pid_t pid = getppid(); |
| ASSERT_EQ(ptrace(PTRACE_PEEKDATA, pid, &kWord, nullptr), -1); |
| EXPECT_EQ(errno, ESRCH) << ErrnoMessage("ptrace"); |
| { |
| ScopedPtraceAttach attachment; |
| ASSERT_EQ(attachment.ResetAttach(pid), true); |
| EXPECT_EQ(ptrace(PTRACE_PEEKDATA, pid, &kWord, nullptr), kWord) |
| << ErrnoMessage("ptrace"); |
| } |
| ASSERT_EQ(ptrace(PTRACE_PEEKDATA, pid, &kWord, nullptr), -1); |
| EXPECT_EQ(errno, ESRCH) << ErrnoMessage("ptrace"); |
| } |
| |
| DISALLOW_COPY_AND_ASSIGN(AttachToParentDestructorTest); |
| }; |
| |
| TEST(ScopedPtraceAttach, AttachParentDestructor) { |
| AttachToParentDestructorTest test; |
| test.Run(); |
| } |
| |
| } // namespace |
| } // namespace test |
| } // namespace crashpad |