1 /* 2 * Test whether process_vm_readv and PTRACE_PEEKDATA work. 3 * 4 * Copyright (c) 2016-2017 Dmitry V. Levin <ldv (at) altlinux.org> 5 * Copyright (c) 2017-2018 The strace developers. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. The name of the author may not be used to endorse or promote products 17 * derived from this software without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #include "tests.h" 32 33 #include <errno.h> 34 #include <sys/ptrace.h> 35 #include <signal.h> 36 #include <stdlib.h> 37 #include <unistd.h> 38 #include <sys/uio.h> 39 #include <sys/wait.h> 40 41 #include "test_ucopy.h" 42 43 #ifndef HAVE_PROCESS_VM_READV 44 45 # include <asm/unistd.h> 46 # include "scno.h" 47 static ssize_t 48 strace_process_vm_readv(pid_t pid, 49 const struct iovec *lvec, 50 unsigned long liovcnt, 51 const struct iovec *rvec, 52 unsigned long riovcnt, 53 unsigned long flags) 54 { 55 return syscall(__NR_process_vm_readv, 56 (long) pid, lvec, liovcnt, rvec, riovcnt, flags); 57 } 58 # define process_vm_readv strace_process_vm_readv 59 60 #endif /* !HAVE_PROCESS_VM_READV */ 61 62 static bool 63 call_process_vm_readv(const int pid, long *const addr) 64 { 65 long data = 0; 66 67 const struct iovec local = { 68 .iov_base = &data, 69 .iov_len = sizeof(data) 70 }; 71 const struct iovec remote = { 72 .iov_base = addr, 73 .iov_len = sizeof(*addr) 74 }; 75 76 return process_vm_readv(pid, &local, 1, &remote, 1, 0) == sizeof(data) 77 && data == 1; 78 } 79 80 static bool 81 call_ptrace_peekdata(const int pid, long *const addr) 82 { 83 return ptrace(PTRACE_PEEKDATA, pid, addr, 0) == 1; 84 } 85 86 static bool 87 test_ucopy(bool (*fn)(int pid, long *addr)) 88 { 89 static long data; 90 91 data = 0; 92 bool rc = false; 93 int saved = 0; 94 95 pid_t pid = fork(); 96 if (pid < 0) 97 perror_msg_and_fail("fork"); 98 99 if (!pid) { 100 data = 1; 101 if (ptrace(PTRACE_TRACEME, 0, 0, 0)) 102 perror_msg_and_fail("PTRACE_TRACEME"); 103 raise(SIGSTOP); 104 _exit(0); 105 } 106 107 for (;;) { 108 int status, tracee; 109 110 errno = 0; 111 tracee = wait(&status); 112 if (tracee != pid) { 113 if (errno == EINTR) 114 continue; 115 saved = errno; 116 kill(pid, SIGKILL); 117 errno = saved; 118 perror_msg_and_fail("wait"); 119 } 120 if (WIFEXITED(status)) { 121 if (WEXITSTATUS(status) == 0) 122 break; 123 error_msg_and_fail("unexpected exit status %u", 124 WEXITSTATUS(status)); 125 } 126 if (WIFSIGNALED(status)) 127 error_msg_and_fail("unexpected signal %u", 128 WTERMSIG(status)); 129 if (!WIFSTOPPED(status) || WSTOPSIG(status) != SIGSTOP) { 130 kill(pid, SIGKILL); 131 error_msg_and_fail("unexpected wait status %x", 132 status); 133 } 134 135 errno = 0; 136 rc = fn(pid, &data); 137 if (!rc) 138 saved = errno; 139 140 if (ptrace(PTRACE_CONT, pid, 0, 0)) { 141 saved = errno; 142 kill(pid, SIGKILL); 143 errno = saved; 144 perror_msg_and_fail("PTRACE_CONT"); 145 } 146 } 147 148 if (!rc) 149 errno = saved; 150 return rc; 151 } 152 153 bool 154 test_process_vm_readv(void) 155 { 156 return test_ucopy(call_process_vm_readv); 157 } 158 159 bool 160 test_ptrace_peekdata(void) 161 { 162 return test_ucopy(call_ptrace_peekdata); 163 } 164