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-rw-r--r--REORG.TODO/sysdeps/unix/sysv/linux/dl-execstack.c67
1 files changed, 67 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/unix/sysv/linux/dl-execstack.c b/REORG.TODO/sysdeps/unix/sysv/linux/dl-execstack.c
new file mode 100644
index 0000000000..3c4de1cb46
--- /dev/null
+++ b/REORG.TODO/sysdeps/unix/sysv/linux/dl-execstack.c
@@ -0,0 +1,67 @@
+/* Stack executability handling for GNU dynamic linker.  Linux version.
+   Copyright (C) 2003-2017 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 <ldsodefs.h>
+#include <sys/mman.h>
+#include <errno.h>
+#include <libintl.h>
+#include <stdbool.h>
+#include <stackinfo.h>
+#include <caller.h>
+#include <sysdep.h>
+
+
+extern int __stack_prot attribute_relro attribute_hidden;
+
+
+int
+internal_function
+_dl_make_stack_executable (void **stack_endp)
+{
+  /* This gives us the highest/lowest page that needs to be changed.  */
+  uintptr_t page = ((uintptr_t) *stack_endp
+		    & -(intptr_t) GLRO(dl_pagesize));
+  int result = 0;
+
+  /* Challenge the caller.  */
+  if (__builtin_expect (__check_caller (RETURN_ADDRESS (0),
+					allow_ldso|allow_libpthread) != 0, 0)
+      || __builtin_expect (*stack_endp != __libc_stack_end, 0))
+    return EPERM;
+
+  if (__builtin_expect (__mprotect ((void *) page, GLRO(dl_pagesize),
+				    __stack_prot) == 0, 1))
+    goto return_success;
+  result = errno;
+  goto out;
+
+ return_success:
+  /* Clear the address.  */
+  *stack_endp = NULL;
+
+  /* Remember that we changed the permission.  */
+  GL(dl_stack_flags) |= PF_X;
+
+ out:
+#ifdef check_consistency
+  check_consistency ();
+#endif
+
+  return result;
+}
+rtld_hidden_def (_dl_make_stack_executable)