iconv_open: Fix heap corruption on gconv_init failure [BZ #22026]

Also mangle the __end_fct function pointer on the error handling
path.

1 files changed, 58 insertions, 0 deletions

diff --git a/iconv/tst-gconv-init-failure.c b/iconv/tst-gconv-init-failure.c
new file mode 100644
index 0000000000..92dfbd4ccd
--- /dev/null
+++ b/iconv/tst-gconv-init-failure.c
@@ -0,0 +1,58 @@
+/* Check that module __end_fct is not invoked when the init function fails.
+   Copyright (C) 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 <errno.h>
+#include <iconv.h>
+#include <libgen.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <support/check.h>
+#include <support/support.h>
+#include <support/test-driver.h>
+#include <sys/auxv.h>
+
+/* Test GCONV_PATH to the directory containing the program
+   executable.  */
+static void
+activate_test_gconv_modules (void)
+{
+  unsigned long ptr = getauxval (AT_EXECFN);
+  if (ptr == 0)
+    {
+      printf ("warning: AT_EXECFN not support, cannot run test\n");
+      exit (EXIT_UNSUPPORTED);
+    }
+  char *test_program_directory = dirname (xstrdup ((const char *) ptr));
+  TEST_VERIFY (setenv ("GCONV_PATH", test_program_directory, 1) == 0);
+  free (test_program_directory);
+}
+
+static int
+do_test (void)
+{
+  activate_test_gconv_modules ();
+
+  TEST_VERIFY (iconv_open ("UTF-8", "tst-gconv-init-failure//")
+               == (iconv_t) -1);
+  if (errno != ENOMEM)
+    FAIL_EXIT1 ("unexpected iconv_open error: %m");
+
+  return 0;
+}
+
+#include <support/test-driver.c>