diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/s390/tst-ptrace-singleblock.c')
| -rw-r--r-- | sysdeps/unix/sysv/linux/s390/tst-ptrace-singleblock.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/s390/tst-ptrace-singleblock.c b/sysdeps/unix/sysv/linux/s390/tst-ptrace-singleblock.c new file mode 100644 index 0000000000..c4419516f9 --- /dev/null +++ b/sysdeps/unix/sysv/linux/s390/tst-ptrace-singleblock.c @@ -0,0 +1,178 @@ +/* Testing s390x PTRACE_SINGLEBLOCK ptrace request. + Copyright (C) 2017-2018 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <sys/wait.h> +#include <sys/types.h> +#include <sys/uio.h> +#include <elf.h> +#include <support/xunistd.h> +#include <support/check.h> +#include <string.h> +#include <errno.h> + +/* Ensure that we use the PTRACE_SINGLEBLOCK definition from glibc ptrace.h + in tracer_func. We need the kernel ptrace.h for structs ptrace_area + and gregset_t. */ +#include <sys/ptrace.h> +static const enum __ptrace_request req_singleblock = PTRACE_SINGLEBLOCK; +#include <asm/ptrace.h> + +static void +tracee_func (int pid) +{ + /* Dump the mapping information for manual inspection of the printed + tracee addresses. */ + char str[80]; + sprintf (str, "cat /proc/%d/maps", pid); + puts (str); + system (str); + fflush (stdout); + + TEST_VERIFY_EXIT (ptrace (PTRACE_TRACEME) == 0); + /* Stop tracee. Afterwards the tracer_func can operate. */ + kill (pid, SIGSTOP); + + puts ("The PTRACE_SINGLEBLOCK of the tracer will stop after: " + "brasl %r14,<puts@plt>!"); +} + +static void +tracer_func (int pid) +{ + unsigned long last_break; + ptrace_area parea; + gregset_t regs; + struct iovec parea2; + gregset_t regs2; + + int status; + int ret; +#define MAX_CHARS_IN_BUF 4096 + char buf[MAX_CHARS_IN_BUF + 1]; + size_t buf_count; + + while (1) + { + /* Wait for the tracee to be stopped or exited. */ + wait (&status); + if (WIFEXITED (status)) + break; + + /* Get information about tracee: gprs, last breaking address. */ + parea.len = sizeof (regs); + parea.process_addr = (unsigned long) ®s; + parea.kernel_addr = 0; + TEST_VERIFY_EXIT (ptrace (PTRACE_PEEKUSR_AREA, pid, &parea) == 0); + TEST_VERIFY_EXIT (ptrace (PTRACE_GET_LAST_BREAK, pid, NULL, &last_break) + == 0); + + parea2.iov_len = sizeof (regs2); + parea2.iov_base = ®s2; + TEST_VERIFY_EXIT (ptrace (PTRACE_GETREGSET, pid, NT_PRSTATUS, &parea2) + == 0); + TEST_VERIFY_EXIT (parea2.iov_len == sizeof (regs2)); + + /* Test if gprs obtained by PTRACE_PEEKUSR_AREA and PTRACE_GETREGESET + have the same values. */ + TEST_VERIFY_EXIT (memcmp (®s, ®s2, sizeof (regs)) == 0); + + printf ("child IA: %p last_break: %p\n", + (void *) regs[1], (void *) last_break); + + /* Execute tracee until next taken branch. + + Note: + Before the commit which introduced this testcase, + <glibc>/sysdeps/unix/sysv/linux/s390/sys/ptrace.h + uses ptrace-request 12 for PTRACE_GETREGS, + but <kernel>/include/uapi/linux/ptrace.h + uses 12 for PTRACE_SINGLEBLOCK. + + The s390 kernel has no support for PTRACE_GETREGS! + Thus glibc ptrace.h is adjusted to match kernel ptrace.h. + + The glibc sys/ptrace.h header contains the identifier + PTRACE_SINGLEBLOCK in enum __ptrace_request. In contrast, the kernel + asm/ptrace.h header defines PTRACE_SINGLEBLOCK. + + This test ensures, that PTRACE_SINGLEBLOCK defined in glibc + works as expected. If the kernel would interpret it as + PTRACE_GETREGS, then the tracee will not make any progress + and this testcase will time out or the ptrace call will fail with + different errors. */ + + /* Ptrace request 12 is first done with data argument pointing to + a buffer: + -If request 12 is interpreted as PTRACE_GETREGS, it will store the regs + to buffer without an error. + + -If request 12 is interpreted as PTRACE_SINGLEBLOCK, it will fail + as data argument is used as signal-number and the address of + buf is no valid signal. + + -If request 12 is not implemented, it will also fail. + + Here the test expects that the buffer is untouched and an error is + returned. */ + memset (buf, 'a', MAX_CHARS_IN_BUF); + ret = ptrace (req_singleblock, pid, NULL, buf); + buf [MAX_CHARS_IN_BUF] = '\0'; + buf_count = strspn (buf, "a"); + TEST_VERIFY_EXIT (buf_count == MAX_CHARS_IN_BUF); + TEST_VERIFY_EXIT (ret == -1); + + /* If request 12 is interpreted as PTRACE_GETREGS, the first ptrace + call will touch the buffer which is detected by this test. */ + errno = 0; + ret = ptrace (req_singleblock, pid, NULL, NULL); + if (ret == 0) + { + /* The kernel has support for PTRACE_SINGLEBLOCK ptrace request. */ + TEST_VERIFY_EXIT (errno == 0); + } + else + { + /* The kernel (< 3.15) has no support for PTRACE_SINGLEBLOCK ptrace + request. */ + TEST_VERIFY_EXIT (errno == EIO); + TEST_VERIFY_EXIT (ret == -1); + + /* Just continue tracee until it exits normally. */ + TEST_VERIFY_EXIT (ptrace (PTRACE_CONT, pid, NULL, NULL) == 0); + } + } +} + +static int +do_test (void) +{ + int pid; + pid = xfork (); + if (pid) + tracer_func (pid); + else + tracee_func (getpid ()); + + return EXIT_SUCCESS; +} + +#include <support/test-driver.c> |