From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- .../selftests/breakpoints/breakpoint_test.c | 396 +++++++++++++++++++++ 1 file changed, 396 insertions(+) create mode 100644 tools/testing/selftests/breakpoints/breakpoint_test.c (limited to 'tools/testing/selftests/breakpoints/breakpoint_test.c') diff --git a/tools/testing/selftests/breakpoints/breakpoint_test.c b/tools/testing/selftests/breakpoints/breakpoint_test.c new file mode 100644 index 000000000..120895ab5 --- /dev/null +++ b/tools/testing/selftests/breakpoints/breakpoint_test.c @@ -0,0 +1,396 @@ +/* + * Copyright (C) 2011 Red Hat, Inc., Frederic Weisbecker + * + * Licensed under the terms of the GNU GPL License version 2 + * + * Selftests for breakpoints (and more generally the do_debug() path) in x86. + */ + + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "../kselftest.h" + + +/* Breakpoint access modes */ +enum { + BP_X = 1, + BP_RW = 2, + BP_W = 4, +}; + +static pid_t child_pid; + +/* + * Ensures the child and parent are always "talking" about + * the same test sequence. (ie: that we haven't forgotten + * to call check_trapped() somewhere). + */ +static int nr_tests; + +static void set_breakpoint_addr(void *addr, int n) +{ + int ret; + + ret = ptrace(PTRACE_POKEUSER, child_pid, + offsetof(struct user, u_debugreg[n]), addr); + if (ret) { + perror("Can't set breakpoint addr\n"); + ksft_exit_fail(); + } +} + +static void toggle_breakpoint(int n, int type, int len, + int local, int global, int set) +{ + int ret; + + int xtype, xlen; + unsigned long vdr7, dr7; + + switch (type) { + case BP_X: + xtype = 0; + break; + case BP_W: + xtype = 1; + break; + case BP_RW: + xtype = 3; + break; + } + + switch (len) { + case 1: + xlen = 0; + break; + case 2: + xlen = 4; + break; + case 4: + xlen = 0xc; + break; + case 8: + xlen = 8; + break; + } + + dr7 = ptrace(PTRACE_PEEKUSER, child_pid, + offsetof(struct user, u_debugreg[7]), 0); + + vdr7 = (xlen | xtype) << 16; + vdr7 <<= 4 * n; + + if (local) { + vdr7 |= 1 << (2 * n); + vdr7 |= 1 << 8; + } + if (global) { + vdr7 |= 2 << (2 * n); + vdr7 |= 1 << 9; + } + + if (set) + dr7 |= vdr7; + else + dr7 &= ~vdr7; + + ret = ptrace(PTRACE_POKEUSER, child_pid, + offsetof(struct user, u_debugreg[7]), dr7); + if (ret) { + perror("Can't set dr7"); + ksft_exit_fail(); + } +} + +/* Dummy variables to test read/write accesses */ +static unsigned long long dummy_var[4]; + +/* Dummy functions to test execution accesses */ +static void dummy_func(void) { } +static void dummy_func1(void) { } +static void dummy_func2(void) { } +static void dummy_func3(void) { } + +static void (*dummy_funcs[])(void) = { + dummy_func, + dummy_func1, + dummy_func2, + dummy_func3, +}; + +static int trapped; + +static void check_trapped(void) +{ + /* + * If we haven't trapped, wake up the parent + * so that it notices the failure. + */ + if (!trapped) + kill(getpid(), SIGUSR1); + trapped = 0; + + nr_tests++; +} + +static void write_var(int len) +{ + char *pcval; short *psval; int *pival; long long *plval; + int i; + + for (i = 0; i < 4; i++) { + switch (len) { + case 1: + pcval = (char *)&dummy_var[i]; + *pcval = 0xff; + break; + case 2: + psval = (short *)&dummy_var[i]; + *psval = 0xffff; + break; + case 4: + pival = (int *)&dummy_var[i]; + *pival = 0xffffffff; + break; + case 8: + plval = (long long *)&dummy_var[i]; + *plval = 0xffffffffffffffffLL; + break; + } + check_trapped(); + } +} + +static void read_var(int len) +{ + char cval; short sval; int ival; long long lval; + int i; + + for (i = 0; i < 4; i++) { + switch (len) { + case 1: + cval = *(char *)&dummy_var[i]; + break; + case 2: + sval = *(short *)&dummy_var[i]; + break; + case 4: + ival = *(int *)&dummy_var[i]; + break; + case 8: + lval = *(long long *)&dummy_var[i]; + break; + } + check_trapped(); + } +} + +/* + * Do the r/w/x accesses to trigger the breakpoints. And run + * the usual traps. + */ +static void trigger_tests(void) +{ + int len, local, global, i; + char val; + int ret; + + ret = ptrace(PTRACE_TRACEME, 0, NULL, 0); + if (ret) { + perror("Can't be traced?\n"); + return; + } + + /* Wake up father so that it sets up the first test */ + kill(getpid(), SIGUSR1); + + /* Test instruction breakpoints */ + for (local = 0; local < 2; local++) { + for (global = 0; global < 2; global++) { + if (!local && !global) + continue; + + for (i = 0; i < 4; i++) { + dummy_funcs[i](); + check_trapped(); + } + } + } + + /* Test write watchpoints */ + for (len = 1; len <= sizeof(long); len <<= 1) { + for (local = 0; local < 2; local++) { + for (global = 0; global < 2; global++) { + if (!local && !global) + continue; + write_var(len); + } + } + } + + /* Test read/write watchpoints (on read accesses) */ + for (len = 1; len <= sizeof(long); len <<= 1) { + for (local = 0; local < 2; local++) { + for (global = 0; global < 2; global++) { + if (!local && !global) + continue; + read_var(len); + } + } + } + + /* Icebp trap */ + asm(".byte 0xf1\n"); + check_trapped(); + + /* Int 3 trap */ + asm("int $3\n"); + check_trapped(); + + kill(getpid(), SIGUSR1); +} + +static void check_success(const char *msg) +{ + const char *msg2; + int child_nr_tests; + int status; + + /* Wait for the child to SIGTRAP */ + wait(&status); + + msg2 = "Failed"; + + if (WSTOPSIG(status) == SIGTRAP) { + child_nr_tests = ptrace(PTRACE_PEEKDATA, child_pid, + &nr_tests, 0); + if (child_nr_tests == nr_tests) + msg2 = "Ok"; + if (ptrace(PTRACE_POKEDATA, child_pid, &trapped, 1)) { + perror("Can't poke\n"); + ksft_exit_fail(); + } + } + + nr_tests++; + + printf("%s [%s]\n", msg, msg2); +} + +static void launch_instruction_breakpoints(char *buf, int local, int global) +{ + int i; + + for (i = 0; i < 4; i++) { + set_breakpoint_addr(dummy_funcs[i], i); + toggle_breakpoint(i, BP_X, 1, local, global, 1); + ptrace(PTRACE_CONT, child_pid, NULL, 0); + sprintf(buf, "Test breakpoint %d with local: %d global: %d", + i, local, global); + check_success(buf); + toggle_breakpoint(i, BP_X, 1, local, global, 0); + } +} + +static void launch_watchpoints(char *buf, int mode, int len, + int local, int global) +{ + const char *mode_str; + int i; + + if (mode == BP_W) + mode_str = "write"; + else + mode_str = "read"; + + for (i = 0; i < 4; i++) { + set_breakpoint_addr(&dummy_var[i], i); + toggle_breakpoint(i, mode, len, local, global, 1); + ptrace(PTRACE_CONT, child_pid, NULL, 0); + sprintf(buf, "Test %s watchpoint %d with len: %d local: " + "%d global: %d", mode_str, i, len, local, global); + check_success(buf); + toggle_breakpoint(i, mode, len, local, global, 0); + } +} + +/* Set the breakpoints and check the child successfully trigger them */ +static void launch_tests(void) +{ + char buf[1024]; + int len, local, global, i; + + /* Instruction breakpoints */ + for (local = 0; local < 2; local++) { + for (global = 0; global < 2; global++) { + if (!local && !global) + continue; + launch_instruction_breakpoints(buf, local, global); + } + } + + /* Write watchpoint */ + for (len = 1; len <= sizeof(long); len <<= 1) { + for (local = 0; local < 2; local++) { + for (global = 0; global < 2; global++) { + if (!local && !global) + continue; + launch_watchpoints(buf, BP_W, len, + local, global); + } + } + } + + /* Read-Write watchpoint */ + for (len = 1; len <= sizeof(long); len <<= 1) { + for (local = 0; local < 2; local++) { + for (global = 0; global < 2; global++) { + if (!local && !global) + continue; + launch_watchpoints(buf, BP_RW, len, + local, global); + } + } + } + + /* Icebp traps */ + ptrace(PTRACE_CONT, child_pid, NULL, 0); + check_success("Test icebp"); + + /* Int 3 traps */ + ptrace(PTRACE_CONT, child_pid, NULL, 0); + check_success("Test int 3 trap"); + + ptrace(PTRACE_CONT, child_pid, NULL, 0); +} + +int main(int argc, char **argv) +{ + pid_t pid; + int ret; + + pid = fork(); + if (!pid) { + trigger_tests(); + return 0; + } + + child_pid = pid; + + wait(NULL); + + launch_tests(); + + wait(NULL); + + return ksft_exit_pass(); +} -- cgit v1.2.3-54-g00ecf