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 <j...@ziepe.ca>
Cc: Leon Romanovsky <l...@kernel.org>
Cc: linux-r...@vger.kernel.org
Signed-off-by: Kees Cook <keesc...@chromium.org>
---
 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


Reply via email to