Introduce xmallocarray, an overflow checking variant of xmalloc.

2014-06-17  Janne Blomqvist  <jb@gcc.gnu.org>

	* libgfortran.h (xmallocarray): New prototype.
	* runtime/memory.c (xmallocarray): New function.
	(xcalloc): Check for nonzero separately instead of multiplying.
	* generated/*.c: Regenerated.
	* intrinsics/cshift0.c (cshift0): Call xmallocarray instead of
	xmalloc.
	* intrinsics/eoshift0.c (eoshift0): Likewise.
	* intrinsics/eoshift2.c (eoshift2): Likewise.
	* intrinsics/pack_generic.c (pack_internal): Likewise.
	(pack_s_internal): Likewise.
	* intrinsics/reshape_generic.c (reshape_internal): Likewise.
	* intrinsics/spread_generic.c (spread_internal): Likewise.
	(spread_internal_scalar): Likewise.
	* intrinsics/string_intrinsics_inc.c (string_trim): Likewise.
	(string_minmax): Likewise.
	* intrinsics/transpose_generic.c (transpose_internal): Likewise.
	* intrinsics/unpack_generic.c (unpack_internal): Likewise.
	* io/list_read.c (nml_touch_nodes): Don't cast xmalloc return value.
	* io/transfer.c (st_set_nml_var): Call xmallocarray instead of
	xmalloc.
	* io/unit.c (get_internal_unit): Likewise.
	(filename_from_unit): Don't cast xmalloc return value.
	* io/write.c (nml_write_obj): Likewise, formatting.
	* m4/bessel.m4 (bessel_jn_r'rtype_kind`): Call xmallocarray
	instead of xmalloc.
	(besse_yn_r'rtype_kind`): Likewise.
	* m4/cshift1.m4 (cshift1): Likewise.
	* m4/eoshift1.m4 (eoshift1): Likewise.
	* m4/eoshift3.m4 (eoshift3): Likewise.
	* m4/iforeach.m4: Likewise.
	* m4/ifunction.m4: Likewise.
	* m4/ifunction_logical.m4 (name`'rtype_qual`_'atype_code):
	Likewise.
	* m4/in_pack.m4 (internal_pack_'rtype_ccode`): Likewise.
	* m4/matmul.m4 (matmul_'rtype_code`): Likewise.
	* m4/matmull.m4 (matmul_'rtype_code`): Likewise.
	* m4/pack.m4 (pack_'rtype_code`): Likewise.
	* m4/reshape.m4 (reshape_'rtype_ccode`): Likewise.
	* m4/shape.m4 (shape_'rtype_kind`): Likewise.
	* m4/spread.m4 (spread_'rtype_code`): Likewise.
	(spread_scalar_'rtype_code`): Likewise.
	* m4/transpose.m4 (transpose_'rtype_code`): Likewise.
	* m4/unpack.m4 (unpack0_'rtype_code`): Likewise.
	(unpack1_'rtype_code`): Likewise.
	* runtime/convert_char.c (convert_char1_to_char4): Likewise.
	(convert_char4_to_char1): Simplify.
	* runtime/environ.c (init_unformatted): Call xmallocarray instead
	of xmalloc.
	* runtime/in_pack_generic.c (internal_pack): Likewise.

From-SVN: r211721

4 files changed, 32 insertions, 5 deletions

diff --git a/libgfortran/runtime/convert_char.c b/libgfortran/runtime/convert_char.c
index aa819912..c3cd1c2 100644
--- a/libgfortran/runtime/convert_char.c
+++ b/libgfortran/runtime/convert_char.c
@@ -44,7 +44,7 @@ convert_char1_to_char4 (gfc_char4_t **dst, gfc_charlen_type len,
   gfc_charlen_type i, l;
 
   l = len > 0 ? len : 0;
-  *dst = xmalloc ((l + 1) * sizeof (gfc_char4_t));
+  *dst = xmallocarray ((l + 1), sizeof (gfc_char4_t));
 
   for (i = 0; i < l; i++)
     (*dst)[i] = src[i];
@@ -60,7 +60,7 @@ convert_char4_to_char1 (unsigned char **dst, gfc_charlen_type len,
   gfc_charlen_type i, l;
 
   l = len > 0 ? len : 0;
-  *dst = xmalloc ((l + 1) * sizeof (unsigned char));
+  *dst = xmalloc (l + 1);
 
   for (i = 0; i < l; i++)
     (*dst)[i] = src[i];
diff --git a/libgfortran/runtime/environ.c b/libgfortran/runtime/environ.c
index 0c0e930..1095f44 100644
--- a/libgfortran/runtime/environ.c
+++ b/libgfortran/runtime/environ.c
@@ -837,7 +837,7 @@ void init_unformatted (variable * v)
     }
   else
     {
-      elist = xmalloc (unit_count * sizeof (exception_t));
+      elist = xmallocarray (unit_count, sizeof (exception_t));
       do_count = 0;
       p = val;
       do_parse ();
diff --git a/libgfortran/runtime/in_pack_generic.c b/libgfortran/runtime/in_pack_generic.c
index 1b8c558..aab155d 100644
--- a/libgfortran/runtime/in_pack_generic.c
+++ b/libgfortran/runtime/in_pack_generic.c
@@ -180,7 +180,7 @@ internal_pack (gfc_array_char * source)
     return source->base_addr;
 
    /* Allocate storage for the destination.  */
-  destptr = xmalloc (ssize * size);
+  destptr = xmallocarray (ssize, size);
   dest = (char *)destptr;
   src = source->base_addr;
   stride0 = stride[0] * size;
diff --git a/libgfortran/runtime/memory.c b/libgfortran/runtime/memory.c
index b18b505..501d870 100644
--- a/libgfortran/runtime/memory.c
+++ b/libgfortran/runtime/memory.c
@@ -25,6 +25,11 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 
 #include "libgfortran.h"
 #include <stdlib.h>
+#include <errno.h>
+
+#ifndef SIZE_MAX
+#define SIZE_MAX ((size_t)-1)
+#endif
 
 
 void *
@@ -44,12 +49,34 @@ xmalloc (size_t n)
 }
 
 
+void *
+xmallocarray (size_t nmemb, size_t size)
+{
+  void *p;
+
+  if (!nmemb || !size)
+    size = nmemb = 1;
+  else if (nmemb > SIZE_MAX / size)
+    {
+      errno = ENOMEM;
+      os_error ("Integer overflow in xmallocarray");
+    }
+
+  p = malloc (nmemb * size);
+
+  if (!p)
+    os_error ("Memory allocation failed in xmallocarray");
+
+  return p;
+}
+
+
 /* calloc wrapper that aborts on error.  */
 
 void *
 xcalloc (size_t nmemb, size_t size)
 {
-  if (nmemb * size == 0)
+  if (!nmemb || !size)
     nmemb = size = 1;
 
   void *p = calloc (nmemb, size);