dmaengine: sf-pdma: Annotate struct sf_pdma with __counted_by

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 sf_pdma.

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

Cc: Vinod Koul <vkoul@kernel.org>
Cc: Green Wan <green.wan@sifive.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230817235859.49846-9-keescook@chromium.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/dma/sf-pdma/sf-pdma.h b/drivers/dma/sf-pdma/sf-pdma.h
index 5c398a83b491aa3af5c1f505af95ea1f0ddb445b..d05772b5d8d3fd3e0bee8d984eb41916c80e5214 100644 (file)
--- a/drivers/dma/sf-pdma/sf-pdma.h
+++ b/drivers/dma/sf-pdma/sf-pdma.h
@@ -113,7 +113,7 @@ struct sf_pdma {
        void __iomem            *membase;
        void __iomem            *mappedbase;
        u32                     n_chans;
-       struct sf_pdma_chan     chans[];
+       struct sf_pdma_chan     chans[] __counted_by(n_chans);
 };
 
 #endif /* _SF_PDMA_H */