mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-14 07:10:05 +00:00
7ff4da3dc2
If close() on infd and outfd succeeded, reset the fd numbers so that
we don't attempt to close them again.
Reviewed-by: Arjun Shankar <arjun@redhat.com>
(cherry picked from commit 45caed9d67
)
238 lines
6.1 KiB
C
238 lines
6.1 KiB
C
/* Capture output from a subprocess.
|
|
Copyright (C) 2017-2021 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
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#include <support/subprocess.h>
|
|
#include <support/capture_subprocess.h>
|
|
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <stdlib.h>
|
|
#include <support/check.h>
|
|
#include <support/xunistd.h>
|
|
#include <support/xsocket.h>
|
|
#include <support/xspawn.h>
|
|
#include <support/support.h>
|
|
#include <support/test-driver.h>
|
|
|
|
static void
|
|
transfer (const char *what, struct pollfd *pfd, struct xmemstream *stream)
|
|
{
|
|
if (pfd->revents != 0)
|
|
{
|
|
char buf[1024];
|
|
ssize_t ret = TEMP_FAILURE_RETRY (read (pfd->fd, buf, sizeof (buf)));
|
|
if (ret < 0)
|
|
{
|
|
support_record_failure ();
|
|
printf ("error: reading from subprocess %s: %m\n", what);
|
|
pfd->events = 0;
|
|
pfd->revents = 0;
|
|
}
|
|
else if (ret == 0)
|
|
{
|
|
/* EOF reached. Stop listening. */
|
|
pfd->events = 0;
|
|
pfd->revents = 0;
|
|
}
|
|
else
|
|
/* Store the data just read. */
|
|
TEST_VERIFY (fwrite (buf, ret, 1, stream->out) == 1);
|
|
}
|
|
}
|
|
|
|
static void
|
|
support_capture_poll (struct support_capture_subprocess *result,
|
|
struct support_subprocess *proc)
|
|
{
|
|
struct pollfd fds[2] =
|
|
{
|
|
{ .fd = proc->stdout_pipe[0], .events = POLLIN },
|
|
{ .fd = proc->stderr_pipe[0], .events = POLLIN },
|
|
};
|
|
|
|
do
|
|
{
|
|
xpoll (fds, 2, -1);
|
|
transfer ("stdout", &fds[0], &result->out);
|
|
transfer ("stderr", &fds[1], &result->err);
|
|
}
|
|
while (fds[0].events != 0 || fds[1].events != 0);
|
|
|
|
xfclose_memstream (&result->out);
|
|
xfclose_memstream (&result->err);
|
|
|
|
result->status = support_process_wait (proc);
|
|
}
|
|
|
|
struct support_capture_subprocess
|
|
support_capture_subprocess (void (*callback) (void *), void *closure)
|
|
{
|
|
struct support_capture_subprocess result;
|
|
xopen_memstream (&result.out);
|
|
xopen_memstream (&result.err);
|
|
|
|
struct support_subprocess proc = support_subprocess (callback, closure);
|
|
|
|
support_capture_poll (&result, &proc);
|
|
return result;
|
|
}
|
|
|
|
struct support_capture_subprocess
|
|
support_capture_subprogram (const char *file, char *const argv[])
|
|
{
|
|
struct support_capture_subprocess result;
|
|
xopen_memstream (&result.out);
|
|
xopen_memstream (&result.err);
|
|
|
|
struct support_subprocess proc = support_subprogram (file, argv);
|
|
|
|
support_capture_poll (&result, &proc);
|
|
return result;
|
|
}
|
|
|
|
/* Copies the executable into a restricted directory, so that we can
|
|
safely make it SGID with the TARGET group ID. Then runs the
|
|
executable. */
|
|
static int
|
|
copy_and_spawn_sgid (char *child_id, gid_t gid)
|
|
{
|
|
char *dirname = xasprintf ("%s/tst-tunables-setuid.%jd",
|
|
test_dir, (intmax_t) getpid ());
|
|
char *execname = xasprintf ("%s/bin", dirname);
|
|
int infd = -1;
|
|
int outfd = -1;
|
|
int ret = 1, status = 1;
|
|
|
|
TEST_VERIFY (mkdir (dirname, 0700) == 0);
|
|
if (support_record_failure_is_failed ())
|
|
goto err;
|
|
|
|
infd = open ("/proc/self/exe", O_RDONLY);
|
|
if (infd < 0)
|
|
FAIL_UNSUPPORTED ("unsupported: Cannot read binary from procfs\n");
|
|
|
|
outfd = open (execname, O_WRONLY | O_CREAT | O_EXCL, 0700);
|
|
TEST_VERIFY (outfd >= 0);
|
|
if (support_record_failure_is_failed ())
|
|
goto err;
|
|
|
|
char buf[4096];
|
|
for (;;)
|
|
{
|
|
ssize_t rdcount = read (infd, buf, sizeof (buf));
|
|
TEST_VERIFY (rdcount >= 0);
|
|
if (support_record_failure_is_failed ())
|
|
goto err;
|
|
if (rdcount == 0)
|
|
break;
|
|
char *p = buf;
|
|
char *end = buf + rdcount;
|
|
while (p != end)
|
|
{
|
|
ssize_t wrcount = write (outfd, buf, end - p);
|
|
if (wrcount == 0)
|
|
errno = ENOSPC;
|
|
TEST_VERIFY (wrcount > 0);
|
|
if (support_record_failure_is_failed ())
|
|
goto err;
|
|
p += wrcount;
|
|
}
|
|
}
|
|
TEST_VERIFY (fchown (outfd, getuid (), gid) == 0);
|
|
if (support_record_failure_is_failed ())
|
|
goto err;
|
|
TEST_VERIFY (fchmod (outfd, 02750) == 0);
|
|
if (support_record_failure_is_failed ())
|
|
goto err;
|
|
TEST_VERIFY (close (outfd) == 0);
|
|
if (support_record_failure_is_failed ())
|
|
goto err;
|
|
TEST_VERIFY (close (infd) == 0);
|
|
if (support_record_failure_is_failed ())
|
|
goto err;
|
|
|
|
/* We have the binary, now spawn the subprocess. Avoid using
|
|
support_subprogram because we only want the program exit status, not the
|
|
contents. */
|
|
ret = 0;
|
|
infd = outfd = -1;
|
|
|
|
char * const args[] = {execname, child_id, NULL};
|
|
|
|
status = support_subprogram_wait (args[0], args);
|
|
|
|
err:
|
|
if (outfd >= 0)
|
|
close (outfd);
|
|
if (infd >= 0)
|
|
close (infd);
|
|
if (execname != NULL)
|
|
{
|
|
unlink (execname);
|
|
free (execname);
|
|
}
|
|
if (dirname != NULL)
|
|
{
|
|
rmdir (dirname);
|
|
free (dirname);
|
|
}
|
|
|
|
if (ret != 0)
|
|
FAIL_EXIT1("Failed to make sgid executable for test\n");
|
|
|
|
return status;
|
|
}
|
|
|
|
int
|
|
support_capture_subprogram_self_sgid (char *child_id)
|
|
{
|
|
gid_t target = 0;
|
|
const int count = 64;
|
|
gid_t groups[count];
|
|
|
|
/* Get a GID which is not our current GID, but is present in the
|
|
supplementary group list. */
|
|
int ret = getgroups (count, groups);
|
|
if (ret < 0)
|
|
FAIL_UNSUPPORTED("Could not get group list for user %jd\n",
|
|
(intmax_t) getuid ());
|
|
|
|
gid_t current = getgid ();
|
|
for (int i = 0; i < ret; ++i)
|
|
{
|
|
if (groups[i] != current)
|
|
{
|
|
target = groups[i];
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (target == 0)
|
|
FAIL_UNSUPPORTED("Could not find a suitable GID for user %jd\n",
|
|
(intmax_t) getuid ());
|
|
|
|
return copy_and_spawn_sgid (child_id, target);
|
|
}
|
|
|
|
void
|
|
support_capture_subprocess_free (struct support_capture_subprocess *p)
|
|
{
|
|
free (p->out.buffer);
|
|
free (p->err.buffer);
|
|
}
|