[PATCH 1/7] RDMA: Annotate struct rdma_hw_stats 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 rdma_hw_stats.

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

Cc: Jason Gunthorpe <jgg@xxxxxxxx>
Cc: Leon Romanovsky <leon@xxxxxxxxxx>
Cc: linux-rdma@xxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
 include/rdma/ib_verbs.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index e36c0d9aad27..79bcdebbe228 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -607,7 +607,7 @@ struct rdma_hw_stats {
 	const struct rdma_stat_desc *descs;
 	unsigned long	*is_disabled;
 	int		num_counters;
-	u64		value[];
+	u64		value[] __counted_by(num_counters);
 };
 
 #define RDMA_HW_STATS_DEFAULT_LIFESPAN 10
-- 
2.34.1