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* [PATCH] io: Fix record locking contants on 32 bit arch with 64 bit default time_t (BZ#30477)
@ 2023-05-24 19:31 Adhemerval Zanella
  2023-05-25  8:48 ` Florian Weimer
  2023-05-25  9:00 ` Andreas Schwab
  0 siblings, 2 replies; 4+ messages in thread
From: Adhemerval Zanella @ 2023-05-24 19:31 UTC (permalink / raw)
  To: libc-alpha, Bo YU

For architecture with default 64 bit time_t support, the kernel
does not provide LFS and non-LFS values for F_GETLK, F_GETLK, and
F_GETLK (the default value used for 64 bit architecture are used).

This is might be considered an ABI break, but the currenct exported
values is bogus anyway.

The POSIX lockf is not affected since it is aliased to lockf64,
which already uses the LFS values.

Checked on i686-linux-gnu and the new tests on a riscv32.
---
 io/Makefile                                |   1 +
 io/tst-fcntl-lock.c                        | 218 +++++++++++++++++++++
 sysdeps/unix/sysv/linux/bits/fcntl-linux.h |   2 +-
 3 files changed, 220 insertions(+), 1 deletion(-)
 create mode 100644 io/tst-fcntl-lock.c

diff --git a/io/Makefile b/io/Makefile
index db886ca26f..d573064ecc 100644
--- a/io/Makefile
+++ b/io/Makefile
@@ -175,6 +175,7 @@ tests := \
   tst-fchmodat \
   tst-fchownat \
   tst-fcntl \
+  tst-fcntl-lock \
   tst-fstatat \
   tst-fts \
   tst-fts-lfs \
diff --git a/io/tst-fcntl-lock.c b/io/tst-fcntl-lock.c
new file mode 100644
index 0000000000..8735b147f7
--- /dev/null
+++ b/io/tst-fcntl-lock.c
@@ -0,0 +1,218 @@
+/* Test for advisory record locking.
+   Copyright (C) 2023 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License
+   as published by the Free Software Foundation; either version 2
+   of the License, or (at your option) any later version.
+
+   This program 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, see <https://www.gnu.org/licenses/>.
+*/
+
+#include <fcntl.h>
+#include <unistd.h>
+#include <errno.h>
+#include <stdint.h>
+
+#include <support/temp_file.h>
+#include <support/capture_subprocess.h>
+#include <support/check.h>
+
+static char *temp_filename;
+static int temp_fd;
+
+static void
+do_prepare (int argc, char **argv)
+{
+  temp_fd = create_temp_file ("tst-fcntl-lock.", &temp_filename);
+  TEST_VERIFY_EXIT (temp_fd != -1);
+}
+#define PREPARE do_prepare
+
+/* This is essentially the POSIX lockf.  */
+
+enum fcntl_lock_cmd
+{
+  TEST,
+  ULOCK,
+  LOCK,
+  TLOCK,
+};
+
+static inline __attribute_artificial__ int
+fcntl_lockf (int fd, enum fcntl_lock_cmd cmd, off_t len)
+{
+  struct flock fl = {
+    .l_type = F_WRLCK,
+    .l_whence = SEEK_CUR,
+    .l_len = len
+  };
+
+  switch (cmd)
+    {
+    case TEST:
+      fl.l_type = F_RDLCK;
+      if (fcntl (fd, F_GETLK, &fl) < 0)
+	return -1;
+      if (fl.l_type == F_UNLCK || fl.l_pid == getpid ())
+	return 0;
+      errno = EACCES;
+      return -1;
+
+    case ULOCK:
+      fl.l_type = F_UNLCK;
+      return fcntl (fd, F_SETLK, &fl);
+
+    case LOCK:
+      return fcntl (fd, F_SETLKW, &fl);
+
+    case TLOCK:
+      return fcntl (fd, F_SETLK, &fl);
+    }
+
+  errno = EINVAL;
+  return -1;
+}
+
+static inline __attribute_artificial__ int
+fcntl64_lockf (int fd, enum fcntl_lock_cmd cmd, off64_t len64)
+{
+  struct flock64 fl64 = {
+    .l_type = F_WRLCK,
+    .l_whence = SEEK_CUR,
+    .l_len = len64
+  };
+
+  switch (cmd)
+    {
+    case TEST:
+      fl64.l_type = F_RDLCK;
+      if (fcntl64 (fd, F_GETLK64, &fl64) < 0)
+	return -1;
+      if (fl64.l_type == F_UNLCK || fl64.l_pid == getpid ())
+	return 0;
+      errno = EACCES;
+      return -1;
+
+    case ULOCK:
+      fl64.l_type = F_UNLCK;
+      return fcntl64 (fd, F_SETLK64, &fl64);
+
+    case LOCK:
+      return fcntl64 (fd, F_SETLKW64, &fl64);
+
+    case TLOCK:
+      return fcntl64 (fd, F_SETLK64, &fl64);
+    }
+
+  errno = EINVAL;
+  return -1;
+}
+
+static void
+do_test_child_lockf (void *closure)
+{
+  /* Check if parent has [0, 1024) locked.  */
+  TEST_COMPARE (lseek (temp_fd, 0, SEEK_SET), 0);
+  TEST_COMPARE (fcntl_lockf (temp_fd, TLOCK, 1024), -1);
+  TEST_COMPARE (errno, EAGAIN);
+  TEST_COMPARE (fcntl_lockf (temp_fd, TEST, 1024), -1);
+  TEST_COMPARE (errno, EACCES);
+  /* Also Check if parent has last 1024 bytes locked.  */
+  TEST_COMPARE (lseek (temp_fd, INT32_MAX-1024, SEEK_SET), INT32_MAX-1024);
+  TEST_COMPARE (fcntl_lockf (temp_fd, TEST, 1024), -1);
+
+  /* And try to lock [1024, 2048).  */
+  TEST_COMPARE (lseek (temp_fd, 1024, SEEK_SET), 1024);
+  TEST_COMPARE (fcntl_lockf (temp_fd, LOCK, 1024), 0);
+
+  /* Check if non-LFS interface cap access to 32-bif off_t.  */
+  TEST_COMPARE (lseek64 (temp_fd, (off64_t)INT32_MAX, SEEK_SET),
+		(off64_t)INT32_MAX);
+  TEST_COMPARE (fcntl64_lockf (temp_fd, TEST, 1024), 0);
+}
+
+static void
+do_test_child_lockf64 (void *closure)
+{
+  /* Check if parent has [0, 1024) locked.  */
+  TEST_COMPARE (lseek64 (temp_fd, 0, SEEK_SET), 0);
+  TEST_COMPARE (fcntl64_lockf (temp_fd, TLOCK, 1024), -1);
+  TEST_COMPARE (errno, EAGAIN);
+  TEST_COMPARE (fcntl64_lockf (temp_fd, TEST, 1024), -1);
+  TEST_COMPARE (errno, EACCES);
+  /* Also Check if parent has last 1024 bytes locked.  */
+  TEST_COMPARE (lseek64 (temp_fd, INT32_MAX-1024, SEEK_SET), INT32_MAX-1024);
+  TEST_COMPARE (fcntl64_lockf (temp_fd, TEST, 1024), -1);
+
+  /* And try to lock [1024, 2048).  */
+  TEST_COMPARE (lseek64 (temp_fd, 1024, SEEK_SET), 1024);
+  TEST_COMPARE (fcntl64_lockf (temp_fd, LOCK, 1024), 0);
+
+  /* And also [INT32_MAX, INT32_MAX+1024).  */
+  {
+    off64_t off = (off64_t)INT32_MAX;
+    TEST_COMPARE (lseek64 (temp_fd, off, SEEK_SET), off);
+    TEST_COMPARE (fcntl64_lockf (temp_fd, LOCK, 1024), 0);
+  }
+
+  /* Check if [INT32_MAX+1024, INT64_MAX) is locked.  */
+  {
+    off64_t off = (off64_t)INT32_MAX+1024;
+    TEST_COMPARE (lseek64 (temp_fd, off, SEEK_SET), off);
+    TEST_COMPARE (fcntl64_lockf (temp_fd, TLOCK, 1024), -1);
+    TEST_COMPARE (errno, EAGAIN);
+    TEST_COMPARE (fcntl64_lockf (temp_fd, TEST, 1024), -1);
+    TEST_COMPARE (errno, EACCES);
+  }
+}
+
+static int
+do_test (void)
+{
+  /* Basic tests to check if a lock can be obtained and checked.  */
+  TEST_COMPARE (fcntl_lockf (temp_fd, LOCK, 1024), 0);
+  TEST_COMPARE (fcntl_lockf (temp_fd, LOCK, INT32_MAX), 0);
+  TEST_COMPARE (fcntl_lockf (temp_fd, TLOCK, 1024), 0);
+  TEST_COMPARE (fcntl_lockf (temp_fd, TEST, 1024), 0);
+  TEST_COMPARE (lseek (temp_fd, 1024, SEEK_SET), 1024);
+  TEST_COMPARE (fcntl_lockf (temp_fd, ULOCK, 1024), 0);
+  /* Parent process should have ([0, 1024), [2048, INT32_MAX)) ranges locked.  */
+
+  {
+    struct support_capture_subprocess result;
+    result = support_capture_subprocess (do_test_child_lockf, NULL);
+    support_capture_subprocess_check (&result, "lockf", 0, sc_allow_none);
+  }
+
+  if (sizeof (off_t) != sizeof (off64_t))
+    {
+      /* Check if previously locked regions with LFS symbol.  */
+      TEST_COMPARE (lseek (temp_fd, 0, SEEK_SET), 0);
+      TEST_COMPARE (fcntl64_lockf (temp_fd, LOCK, 1024), 0);
+      TEST_COMPARE (fcntl64_lockf (temp_fd, TLOCK, 1024), 0);
+      TEST_COMPARE (fcntl64_lockf (temp_fd, TEST, 1024), 0);
+      /* Lock region [INT32_MAX+1024, INT64_MAX).  */
+      off64_t off = (off64_t)INT32_MAX + 1024;
+      TEST_COMPARE (lseek64 (temp_fd, off, SEEK_SET), off);
+      TEST_COMPARE (fcntl64_lockf (temp_fd, LOCK, 1024), 0);
+      /* Parent process should have ([0, 1024), [2048, INT32_MAX),
+	 [INT32_MAX+1024, INT64_MAX)) ranges locked.  */
+
+      {
+	struct support_capture_subprocess result;
+	result = support_capture_subprocess (do_test_child_lockf64, NULL);
+	support_capture_subprocess_check (&result, "lockf", 0, sc_allow_none);
+      }
+    }
+
+  return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/sysdeps/unix/sysv/linux/bits/fcntl-linux.h b/sysdeps/unix/sysv/linux/bits/fcntl-linux.h
index ca6a0d7516..3c15625599 100644
--- a/sysdeps/unix/sysv/linux/bits/fcntl-linux.h
+++ b/sysdeps/unix/sysv/linux/bits/fcntl-linux.h
@@ -101,7 +101,7 @@
 #endif
 
 #ifndef F_GETLK
-# ifndef __USE_FILE_OFFSET64
+# if !defined(__USE_FILE_OFFSET64) && __TIMESIZE != 64
 #  define F_GETLK	5	/* Get record locking info.  */
 #  define F_SETLK	6	/* Set record locking info (non-blocking).  */
 #  define F_SETLKW	7	/* Set record locking info (blocking).  */
-- 
2.34.1


^ permalink raw reply	[flat|nested] 4+ messages in thread
end of thread, other threads:[~2023-05-25 12:17 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-05-24 19:31 [PATCH] io: Fix record locking contants on 32 bit arch with 64 bit default time_t (BZ#30477) Adhemerval Zanella
2023-05-25  8:48 ` Florian Weimer
2023-05-25 12:17   ` Adhemerval Zanella Netto
2023-05-25  9:00 ` Andreas Schwab

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