@@ -188,6 +188,7 @@ tests := \
tst-closefrom \
tst-copy_file_range \
tst-faccessat \
+ tst-faccessat-setuid \
tst-fchmod-errors \
tst-fchmod-fuse \
tst-fchmodat \
new file mode 100644
@@ -0,0 +1,163 @@
+/* Smoke test for faccessat with different UID/GID combinations. Needs root
+ access.
+ Copyright The GNU Toolchain Authors.
+ 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 <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <pwd.h>
+
+#include <support/check.h>
+#include <support/namespace.h>
+#include <support/support.h>
+#include <support/temp_file.h>
+#include <support/test-driver.h>
+#include <support/xdirent.h>
+#include <support/xunistd.h>
+
+#define SOMEFILE "some-file"
+
+static int dir_fd;
+uid_t users[3];
+gid_t groups[3];
+
+struct test_case
+{
+ int mode;
+ uid_t uid;
+ uid_t euid;
+ gid_t gid;
+ gid_t egid;
+ int flags;
+ bool succeeds;
+};
+
+static void
+run_one_test_child (void *in)
+{
+ struct test_case *t = (struct test_case *) in;
+
+ printf ("TEST: MODE=%s, UID=%d, EUID=%d, GID=%d, EGID=%d, FLAGS=%s: ",
+ t->mode == R_OK ? "R_OK" : "W_OK", t->uid, t->euid, t->gid, t->egid,
+ t->flags ? "AT_EACCESS" : "0");
+
+ if (setregid (t->gid, t->egid) != 0)
+ FAIL_EXIT1 ("Could not change group: %m\n");
+ if (setreuid (t->uid, t->euid) != 0)
+ FAIL_EXIT1 ("Could not change user: %m\n");
+
+ if (faccessat (dir_fd, SOMEFILE, t->mode, t->flags) != 0 && t->succeeds)
+ FAIL_EXIT1 ("faccessat failed: %m\n");
+
+ if (!t->succeeds && errno != EACCES)
+ FAIL_EXIT1 ("Unexpected faccessat failure: %m\n");
+
+ printf ("OK%s\n", !t->succeeds ? " (FAILED with EACCES)" : "");
+}
+
+static void
+run_one_test (int mode, int u, int eu, int g, int eg, int flags, bool succeeds)
+{
+ struct test_case t =
+ {mode, users[u], users[eu], groups[g], groups[eg], flags, succeeds};
+ support_isolate_in_subprocess (run_one_test_child, &t);
+}
+
+static int
+do_test (void)
+{
+
+ /* We need to start as root. */
+ if (getuid () != 0)
+ FAIL_UNSUPPORTED ("Test needs to be run as root (UID 0)\n");
+
+ /* Collect 3 distinct users and groups to test with. */
+ struct passwd *ent = NULL;
+ int count = 0;
+ while ((ent = getpwent ()) != NULL && count < 3)
+ {
+ if (ent->pw_uid == 0 || ent->pw_gid == 0)
+ continue;
+
+ int i = count;
+ bool skip = false;
+ while (i > 0)
+ if (groups[--i] == ent->pw_gid)
+ skip = true;
+
+ if (skip)
+ continue;
+
+ users[count] = ent->pw_uid;
+ groups[count++] = ent->pw_gid;
+ }
+
+ if (count < 3)
+ FAIL_UNSUPPORTED ("Not enough users in the system to do this test\n");
+
+ printf ("Testing with UID/GID:\n");
+ while (--count >= 0)
+ printf (" UID: %d, GID: %d\n", users[count], groups[count]);
+ printf ("\n");
+
+ char *tempdir = support_create_temp_directory ("tst-faccessat-setuid.");
+ dir_fd = xopen (tempdir, O_RDONLY | O_DIRECTORY, 0);
+
+ xfchmod (dir_fd, 0777);
+
+ /* Now, create a file in it, which will be our test case. */
+
+ int fd = openat (dir_fd, SOMEFILE, O_CREAT|O_RDWR|O_EXCL, 0640);
+ if (fd == -1)
+ {
+ if (errno == ENOSYS)
+ FAIL_UNSUPPORTED ("*at functions not supported");
+
+ FAIL_EXIT1 ("file creation failed");
+ }
+ xwrite (fd, "hello", 5);
+
+ if (fchown (fd, users[0], groups[1]) == -1)
+ FAIL_EXIT1 ("fchown failed: %m\n");
+ xclose (fd);
+
+ char *somefile = xasprintf ("%s/" SOMEFILE, tempdir);
+ add_temp_file (somefile);
+
+ /* Finally, run through the combinations. */
+ for (int u = 0; u < 3; u++)
+ for (int eu = 0; eu < 3; eu++)
+ for (int g = 0; g < 3; g++)
+ for (int eg = 0; eg < 3; eg++)
+ {
+ run_one_test (R_OK, u, eu, g, eg, 0, u == 0 || g == 1);
+ run_one_test (W_OK, u, eu, g, eg, 0, u == 0);
+ run_one_test (R_OK, u, eu, g, eg, AT_EACCESS, eu == 0 || eg == 1);
+ run_one_test (W_OK, u, eu, g, eg, AT_EACCESS, eu == 0);
+ }
+
+ xclose (dir_fd);
+ free (tempdir);
+ free (somefile);
+
+ return 0;
+}
+#include <support/test-driver.c>
Add a new test tst-faccessat-setuid that iterates through real and effective UID/GID combination and tests the faccessat() interface for default and AT_EACCESS flags. Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org> --- io/Makefile | 1 + io/tst-faccessat-setuid.c | 163 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 164 insertions(+) create mode 100644 io/tst-faccessat-setuid.c