test: check copy_to/from_user boundary validation
To help avoid an architecture failing to correctly check kernel/user
boundaries when handling copy_to_user, copy_from_user, put_user, or
get_user, perform some simple tests and fail to load if any of them
behave unexpectedly.
Specifically, this is to make sure there is a way to notice if things
like what was fixed in commit 8404663f81d2 ("ARM: 7527/1: uaccess:
explicitly check __user pointer when !CPU_USE_DOMAINS") ever regresses
again, for any architecture.
Additionally, adds new "user" selftest target, which loads this module.
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/lib/Makefile b/lib/Makefile
index b494b9a..98ec3b8 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -32,6 +32,7 @@
obj-y += kstrtox.o
obj-$(CONFIG_TEST_KSTRTOX) += test-kstrtox.o
obj-$(CONFIG_TEST_MODULE) += test_module.o
+obj-$(CONFIG_TEST_USER_COPY) += test_user_copy.o
ifeq ($(CONFIG_DEBUG_KOBJECT),y)
CFLAGS_kobject.o += -DDEBUG