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#define _GNU_SOURCE
#include <stdio.h>
#include <signal.h>
#include <unistd.h>
#include <errno.h>
#include <linux/types.h>
#include <sys/wait.h>
#include <sys/syscall.h>
#include <sys/user.h>
#include <sys/mman.h>
#include "linux/ptrace.h"
static int sys_rt_sigqueueinfo(pid_t tgid, int sig, siginfo_t *uinfo)
{
return syscall(SYS_rt_sigqueueinfo, tgid, sig, uinfo);
}
static int sys_rt_tgsigqueueinfo(pid_t tgid, pid_t tid,
int sig, siginfo_t *uinfo)
{
return syscall(SYS_rt_tgsigqueueinfo, tgid, tid, sig, uinfo);
}
static int sys_ptrace(int request, pid_t pid, void *addr, void *data)
{
return syscall(SYS_ptrace, request, pid, addr, data);
}
#define SIGNR 10
#define TEST_SICODE_PRIV -1
#define TEST_SICODE_SHARE -2
#define err(fmt, ...) \
fprintf(stderr, \
"Error (%s:%d): " fmt, \
__FILE__, __LINE__, ##__VA_ARGS__)
static int check_error_paths(pid_t child)
{
struct ptrace_peeksiginfo_args arg;
int ret, exit_code = -1;
void *addr_rw, *addr_ro;
/*
* Allocate two contiguous pages. The first one is for read-write,
* another is for read-only.
*/
addr_rw = mmap(NULL, 2 * PAGE_SIZE, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (addr_rw == MAP_FAILED) {
err("mmap() failed: %m\n");
return 1;
}
addr_ro = mmap(addr_rw + PAGE_SIZE, PAGE_SIZE, PROT_READ,
MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
if (addr_ro == MAP_FAILED) {
err("mmap() failed: %m\n");
goto out;
}
arg.nr = SIGNR;
arg.off = 0;
/* Unsupported flags */
arg.flags = ~0;
ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg, addr_rw);
if (ret != -1 || errno != EINVAL) {
err("sys_ptrace() returns %d (expected -1),"
" errno %d (expected %d): %m\n",
ret, errno, EINVAL);
goto out;
}
arg.flags = 0;
/* A part of the buffer is read-only */
ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg,
addr_ro - sizeof(siginfo_t) * 2);
if (ret != 2) {
err("sys_ptrace() returns %d (expected 2): %m\n", ret);
goto out;
}
/* Read-only buffer */
ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg, addr_ro);
if (ret != -1 && errno != EFAULT) {
err("sys_ptrace() returns %d (expected -1),"
" errno %d (expected %d): %m\n",
ret, errno, EFAULT);
goto out;
}
exit_code = 0;
out:
munmap(addr_rw, 2 * PAGE_SIZE);
return exit_code;
}
int check_direct_path(pid_t child, int shared, int nr)
{
struct ptrace_peeksiginfo_args arg = {.flags = 0, .nr = nr, .off = 0};
int i, j, ret, exit_code = -1;
siginfo_t siginfo[SIGNR];
int si_code;
if (shared == 1) {
arg.flags = PTRACE_PEEKSIGINFO_SHARED;
si_code = TEST_SICODE_SHARE;
} else {
arg.flags = 0;
si_code = TEST_SICODE_PRIV;
}
for (i = 0; i < SIGNR; ) {
arg.off = i;
ret = sys_ptrace(PTRACE_PEEKSIGINFO, child, &arg, siginfo);
if (ret == -1) {
err("ptrace() failed: %m\n");
goto out;
}
if (ret == 0)
break;
for (j = 0; j < ret; j++, i++) {
if (siginfo[j].si_code == si_code &&
siginfo[j].si_int == i)
continue;
err("%d: Wrong siginfo i=%d si_code=%d si_int=%d\n",
shared, i, siginfo[j].si_code, siginfo[j].si_int);
goto out;
}
}
if (i != SIGNR) {
err("Only %d signals were read\n", i);
goto out;
}
exit_code = 0;
out:
return exit_code;
}
int main(int argc, char *argv[])
{
siginfo_t siginfo[SIGNR];
int i, exit_code = 1;
sigset_t blockmask;
pid_t child;
sigemptyset(&blockmask);
sigaddset(&blockmask, SIGRTMIN);
sigprocmask(SIG_BLOCK, &blockmask, NULL);
child = fork();
if (child == -1) {
err("fork() failed: %m");
return 1;
} else if (child == 0) {
pid_t ppid = getppid();
while (1) {
if (ppid != getppid())
break;
sleep(1);
}
return 1;
}
/* Send signals in process-wide and per-thread queues */
for (i = 0; i < SIGNR; i++) {
siginfo->si_code = TEST_SICODE_SHARE;
siginfo->si_int = i;
sys_rt_sigqueueinfo(child, SIGRTMIN, siginfo);
siginfo->si_code = TEST_SICODE_PRIV;
siginfo->si_int = i;
sys_rt_tgsigqueueinfo(child, child, SIGRTMIN, siginfo);
}
if (sys_ptrace(PTRACE_ATTACH, child, NULL, NULL) == -1)
return 1;
waitpid(child, NULL, 0);
/* Dump signals one by one*/
if (check_direct_path(child, 0, 1))
goto out;
/* Dump all signals for one call */
if (check_direct_path(child, 0, SIGNR))
goto out;
/*
* Dump signal from the process-wide queue.
* The number of signals is not multible to the buffer size
*/
if (check_direct_path(child, 1, 3))
goto out;
if (check_error_paths(child))
goto out;
printf("PASS\n");
exit_code = 0;
out:
if (sys_ptrace(PTRACE_KILL, child, NULL, NULL) == -1)
return 1;
waitpid(child, NULL, 0);
return exit_code;
}
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