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authorZack Weinberg <zackw@panix.com>2017-06-08 15:39:03 -0400
committerZack Weinberg <zackw@panix.com>2017-06-08 15:39:03 -0400
commit5046dbb4a7eba5eccfd258f92f4735c9ffc8d069 (patch)
tree4470480d904b65cf14ca524f96f79eca818c3eaf /REORG.TODO/posix/tst-mmap-offset.c
parent199fc19d3aaaf57944ef036e15904febe877fc93 (diff)
downloadglibc-zack/build-layout-experiment.tar.gz
glibc-zack/build-layout-experiment.tar.xz
glibc-zack/build-layout-experiment.zip
Prepare for radical source tree reorganization. zack/build-layout-experiment
All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).
Diffstat (limited to 'REORG.TODO/posix/tst-mmap-offset.c')
-rw-r--r--REORG.TODO/posix/tst-mmap-offset.c118
1 files changed, 118 insertions, 0 deletions
diff --git a/REORG.TODO/posix/tst-mmap-offset.c b/REORG.TODO/posix/tst-mmap-offset.c
new file mode 100644
index 0000000000..5bb88aab10
--- /dev/null
+++ b/REORG.TODO/posix/tst-mmap-offset.c
@@ -0,0 +1,118 @@
+/* BZ #18877 and #21270 mmap offset test.
+
+   Copyright (C) 2015-2017 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/mman.h>
+
+#include <support/check.h>
+
+static int fd;
+static long int page_shift;
+static char fname[] = "tst-mmap-offset-XXXXXX";
+
+static void
+do_prepare (int argc, char **argv)
+{
+  fd = mkstemp64 (fname);
+  if (fd < 0)
+    FAIL_EXIT1 ("mkstemp failed");
+
+  if (unlink (fname))
+    FAIL_EXIT1 ("unlink failed");
+
+  long sz = sysconf(_SC_PAGESIZE);
+  if (sz == -1)
+    sz = 4096L;
+  page_shift = ffs (sz) - 1;
+}
+
+#define PREPARE do_prepare
+
+
+/* Check if negative offsets are handled correctly by mmap.  */
+static int
+do_test_bz18877 (void)
+{
+  const int prot = PROT_READ | PROT_WRITE;
+  const int flags = MAP_SHARED;
+  const unsigned long length = 0x10000;
+  const unsigned long offset = 0xace00000;
+  const unsigned long size = offset + length;
+  void *addr;
+
+  if (ftruncate64 (fd, size))
+    FAIL_RET ("ftruncate64 failed");
+
+  addr = mmap (NULL, length, prot, flags, fd, offset);
+  if (MAP_FAILED == addr)
+    FAIL_RET ("mmap failed");
+
+  /* This memcpy is likely to SIGBUS if mmap has messed up with offset.  */
+  memcpy (addr, fname, sizeof (fname));
+
+  return 0;
+}
+
+/* Check if invalid offset are handled correctly by mmap.  */
+static int
+do_test_bz21270 (void)
+{
+  /* For architectures with sizeof (off_t) < sizeof (off64_t) mmap is
+     implemented with __SYS_mmap2 syscall and the offset is represented in
+     multiples of page size.  For offset larger than
+     '1 << (page_shift + 8 * sizeof (off_t))' (that is, 1<<44 on system with
+     page size of 4096 bytes) the system call silently truncates the offset.
+     For this case glibc mmap implementation returns EINVAL.  */
+  const int prot = PROT_READ | PROT_WRITE;
+  const int flags = MAP_SHARED;
+  const int64_t offset = 1ULL << (page_shift + 8 * sizeof (uint32_t));
+  const size_t length = 4096;
+
+  void *addr = mmap64 (NULL, length, prot, flags, fd, offset);
+  if (sizeof (off_t) < sizeof (off64_t))
+    {
+      if ((addr != MAP_FAILED) && (errno != EINVAL))
+	FAIL_RET ("mmap succeed");
+    }
+  else
+    {
+      if (addr == MAP_FAILED)
+	FAIL_RET ("mmap failed");
+    }
+
+  return 0;
+}
+
+int
+do_test (void)
+{
+  int ret = 0;
+
+  ret += do_test_bz18877 ();
+  ret += do_test_bz21270 ();
+
+  return ret;
+}
+
+#include <support/test-driver.c>