[PATCH] mtd: Annotate struct lpddr_private with __counted_by

[Kees Cook]

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct lpddr_private.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Miquel Raynal <miquel.raynal at bootlin.com>
Cc: Richard Weinberger <richard at nod.at>
Cc: Vignesh Raghavendra <vigneshr at ti.com>
Cc: linux-mtd at lists.infradead.org
Signed-off-by: Kees Cook <keescook at chromium.org>
---
 include/linux/mtd/qinfo.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/mtd/qinfo.h b/include/linux/mtd/qinfo.h
index 2e3f43788d48..0421f12156b5 100644
--- a/include/linux/mtd/qinfo.h
+++ b/include/linux/mtd/qinfo.h
@@ -24,7 +24,7 @@ struct lpddr_private {
 	struct qinfo_chip *qinfo;
 	int numchips;
 	unsigned long chipshift;
-	struct flchip chips[];
+	struct flchip chips[] __counted_by(numchips);
 };
 
 /* qinfo_query_info structure contains request information for
-- 
2.34.1