x86/vdso: Enable sanitizers for vma.o

The vDSO makefile opts out of all sanitizers (and objtool validation);
however, vma.o is a normal kernel object file (and already has objtool
validation selectively enabled), so turn the sanitizers back on for that
file.

Signed-off-by: Jann Horn <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Marco Elver <[email protected]>
Cc: Paul E. McKenney <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

arch/x86/entry/vdso/Makefile

@@ -30,6 +30,9 @@ vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o
 
 # files to link into kernel
 obj-y				+= vma.o
+KASAN_SANITIZE_vma.o		:= y
+UBSAN_SANITIZE_vma.o		:= y
+KCSAN_SANITIZE_vma.o		:= y
 OBJECT_FILES_NON_STANDARD_vma.o	:= n
 
 # vDSO images to build