increase AT_VECTOR_SIZE to terminate saved_auxv properly

include/asm-powerpc/elf.h has 6 entries in ARCH_DLINFO.  fs/binfmt_elf.c
has 14 unconditional NEW_AUX_ENT entries and 2 conditional NEW_AUX_ENT
entries.  So in the worst case, saved_auxv does not get an AT_NULL entry at
the end.

The saved_auxv array must be terminated with an AT_NULL entry.  Make the
size of mm_struct->saved_auxv arch dependend, based on the number of
ARCH_DLINFO entries.

Signed-off-by: Olaf Hering <olh@suse.de>
Cc: Roland McGrath <roland@redhat.com>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/asm-alpha/elf.h

@@ -155,6 +155,7 @@ extern int alpha_l1d_cacheshape;
 extern int alpha_l2_cacheshape;
 extern int alpha_l3_cacheshape;
 
+/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
 #define ARCH_DLINFO						\
   do {								\
     NEW_AUX_ENT(AT_L1I_CACHESHAPE, alpha_l1i_cacheshape);	\

include/asm-alpha/system.h

@@ -48,6 +48,7 @@
 
 #ifndef __ASSEMBLY__
 #include <linux/kernel.h>
+#define AT_VECTOR_SIZE_ARCH 4 /* entries in ARCH_DLINFO */
 
 /*
  * This is the logout header that should be common to all platforms