[PATCH 20/21] dmaengine: uniphier-xdmac: Annotate struct uniphier_xdmac_device with __counted_by

Kees Cook
2023-08-18T00:10:16Z

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 uniphier_xdmac_device.

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

Cc: Vinod Koul <vkoul@kernel.org>
Cc: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: dmaengine@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Kees Cook <keescook@chromium.org>
---
drivers/dma/uniphier-xdmac.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/dma/uniphier-xdmac.c b/drivers/dma/uniphier-xdmac.c
index dd51522879a7..3a8ee2b173b5 100644
--- a/drivers/dma/uniphier-xdmac.c
+++ b/drivers/dma/uniphier-xdmac.c
@@ -97,7 +97,7 @@ struct uniphier_xdmac_device {
struct dma_device ddev;
void __iomem *reg_base;
int nr_chans;
- struct uniphier_xdmac_chan channels[];
+ struct uniphier_xdmac_chan channels[] __counted_by(nr_chans);
};

static struct uniphier_xdmac_chan *
--
2.34.1