[PATCH 17/21] dmaengine: ti: edma: Annotate struct edma_desc 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 edma_desc.

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

Cc: Vinod Koul <vkoul at kernel.org>
Cc: Peter Ujfalusi <peter.ujfalusi at gmail.com>
Cc: dmaengine at vger.kernel.org
Signed-off-by: Kees Cook <keescook at chromium.org>
---
 drivers/dma/ti/edma.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/dma/ti/edma.c b/drivers/dma/ti/edma.c
index aa8e2e8ac260..9c2b2c4c3882 100644
--- a/drivers/dma/ti/edma.c
+++ b/drivers/dma/ti/edma.c
@@ -202,7 +202,7 @@ struct edma_desc {
 	u32				residue;
 	u32				residue_stat;
 
-	struct edma_pset		pset[];
+	struct edma_pset		pset[] __counted_by(pset_nr);
 };
 
 struct edma_cc;
-- 
2.34.1