[PATCH] x86_64: TASK_SIZE fixes for compatibility mode processes

A malicious 32bit app can have an elf section at 0xffffe000.  During
exec of this app, we will have a memory leak as insert_vm_struct() is
not checking for return value in syscall32_setup_pages() and thus not
freeing the vma allocated for the vsyscall page.

Check the return value and free the vma incase of failure.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>