s390 defines current_stack_pointer as function while all other
architectures use 'register unsigned long asm("<stackptr reg>").
This make codes like the following from check_stack_object() fail:
if (IS_ENABLED(CONFIG_STACK_GROWSUP)) {
if ((void *)current_stack_pointer < obj + len)
return BAD_STACK;
} else {
if (obj < (void *)current_stack_pointer)
return BAD_STACK;
}
because this would compare the address of current_stack_pointer() and
not the stackpointer value.
Reported-by: Karsten Graul <kgraul@linux.ibm.com>
Fixes: 2792d84e6d ("usercopy: Check valid lifetime via stack depth")
Cc: Kees Cook <keescook@chromium.org>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
30de14b188