[PATCH 5.14 413/432] lib/test_stackinit: Fix static initializer test

Greg Kroah-Hartman
2021-09-16T17:52:10Z

From: Kees Cook <keescook@chromium.org>

commit f9398f15605a50110bf570aaa361163a85113dd1 upstream.

The static initializer test got accidentally converted to a dynamic
initializer. Fix this and retain the giant padding hole without using
an aligned struct member.

Fixes: 50ceaa95ea09 ("lib: Introduce test_stackinit module")
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210723221933.3431999-2-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
lib/test_stackinit.c | 20 +++++++-------------
1 file changed, 7 insertions(+), 13 deletions(-)

--- a/lib/test_stackinit.c
+++ b/lib/test_stackinit.c
@@ -67,10 +67,10 @@ static bool range_contains(char *haystac
#define INIT_STRUCT_none /**/
#define INIT_STRUCT_zero = { }
#define INIT_STRUCT_static_partial = { .two = 0, }
-#define INIT_STRUCT_static_all = { .one = arg->one, \
- .two = arg->two, \
- .three = arg->three, \
- .four = arg->four, \
+#define INIT_STRUCT_static_all = { .one = 0, \
+ .two = 0, \
+ .three = 0, \
+ .four = 0, \
}
#define INIT_STRUCT_dynamic_partial = { .two = arg->two, }
#define INIT_STRUCT_dynamic_all = { .one = arg->one, \
@@ -84,8 +84,7 @@ static bool range_contains(char *haystac
var.one = 0; \
var.two = 0; \
var.three = 0; \
- memset(&var.four, 0, \
- sizeof(var.four))
+ var.four = 0

/*
* @name: unique string name for the test
@@ -210,18 +209,13 @@ struct test_small_hole {
unsigned long four;
};

-/* Try to trigger unhandled padding in a structure. */
-struct test_aligned {
- u32 internal1;
- u64 internal2;
-} __aligned(64);
-
+/* Trigger unhandled padding in a structure. */
struct test_big_hole {
u8 one;
u8 two;
u8 three;
/* 61 byte padding hole here. */
- struct test_aligned four;
+ u8 four __aligned(64);
} __aligned(64);

struct test_trailing_hole {