[PATCH] mtd: rawnand: ingenic: Annotate struct ingenic_nfc 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 ingenic_nfc.

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

Cc: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
Cc: Harvey Hunt <harveyhuntnexus@xxxxxxxxx>
Cc: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
Cc: Richard Weinberger <richard@xxxxxx>
Cc: Vignesh Raghavendra <vigneshr@xxxxxx>
Cc: linux-mips@xxxxxxxxxxxxxxx
Cc: linux-mtd@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
 drivers/mtd/nand/raw/ingenic/ingenic_nand_drv.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/nand/raw/ingenic/ingenic_nand_drv.c b/drivers/mtd/nand/raw/ingenic/ingenic_nand_drv.c
index 6748226b8bd1..ce9ef4e65597 100644
--- a/drivers/mtd/nand/raw/ingenic/ingenic_nand_drv.c
+++ b/drivers/mtd/nand/raw/ingenic/ingenic_nand_drv.c
@@ -46,7 +46,7 @@ struct ingenic_nfc {
 	struct nand_controller controller;
 	unsigned int num_banks;
 	struct list_head chips;
-	struct ingenic_nand_cs cs[];
+	struct ingenic_nand_cs cs[] __counted_by(num_banks);
 };
 
 struct ingenic_nand {
-- 
2.34.1