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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /tools/testing/selftests/breakpoints/breakpoint_test.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/breakpoints/breakpoint_test.c')
-rw-r--r-- | tools/testing/selftests/breakpoints/breakpoint_test.c | 401 |
1 files changed, 401 insertions, 0 deletions
diff --git a/tools/testing/selftests/breakpoints/breakpoint_test.c b/tools/testing/selftests/breakpoints/breakpoint_test.c new file mode 100644 index 000000000..901b85ea6 --- /dev/null +++ b/tools/testing/selftests/breakpoints/breakpoint_test.c @@ -0,0 +1,401 @@ +/* + * Copyright (C) 2011 Red Hat, Inc., Frederic Weisbecker <fweisbec@redhat.com> + * + * Licensed under the terms of the GNU GPL License version 2 + * + * Selftests for breakpoints (and more generally the do_debug() path) in x86. + */ + + +#include <sys/ptrace.h> +#include <unistd.h> +#include <stddef.h> +#include <sys/user.h> +#include <stdio.h> +#include <stdlib.h> +#include <signal.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <errno.h> +#include <string.h> + +#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) + ksft_exit_fail_msg("Can't set breakpoint addr: %s\n", + strerror(errno)); +} + +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) { + ksft_print_msg("Can't set dr7: %s\n", strerror(errno)); + exit(-1); + } +} + +/* 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) { + ksft_print_msg("Can't be traced? %s\n", strerror(errno)); + 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) +{ + int child_nr_tests; + int status; + int ret; + + /* Wait for the child to SIGTRAP */ + wait(&status); + + ret = 0; + + if (WSTOPSIG(status) == SIGTRAP) { + child_nr_tests = ptrace(PTRACE_PEEKDATA, child_pid, + &nr_tests, 0); + if (child_nr_tests == nr_tests) + ret = 1; + if (ptrace(PTRACE_POKEDATA, child_pid, &trapped, 1)) + ksft_exit_fail_msg("Can't poke: %s\n", strerror(errno)); + } + + nr_tests++; + + if (ret) + ksft_test_result_pass(msg); + else + ksft_test_result_fail(msg); +} + +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\n", + 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\n", + 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\n"); + + /* Int 3 traps */ + ptrace(PTRACE_CONT, child_pid, NULL, 0); + check_success("Test int 3 trap\n"); + + ptrace(PTRACE_CONT, child_pid, NULL, 0); +} + +int main(int argc, char **argv) +{ + pid_t pid; + int ret; + + ksft_print_header(); + + pid = fork(); + if (!pid) { + trigger_tests(); + exit(0); + } + + child_pid = pid; + + wait(NULL); + + launch_tests(); + + wait(NULL); + + ksft_exit_pass(); +} |