RDMA: Annotate struct rdma_hw_stats 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 rdma_hw_stats.

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

Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: linux-rdma@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230929180431.3005464-1-keescook@chromium.org
Signed-off-by: Leon Romanovsky <leon@kernel.org>

diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index fd61c3a56fa7e62ee83619dd9ea2456afb29d569..f8f0d3a4fdecf861bf25c811659f9f9d883e2e27 100644 (file)
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -608,7 +608,7 @@ 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