net: mana: Annotate struct mana_rxq 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 mana_rxq.

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

Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Long Li <longli@microsoft.com>
Cc: Ajay Sharma <sharmaajay@microsoft.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230922172858.3822653-7-keescook@chromium.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/include/net/mana/mana.h b/include/net/mana/mana.h
index 9f70b43322383a1c3c980ec84b23e919903a7de1..38441be68592b2306fb1596abeda46e894d7a0ed 100644 (file)
--- a/include/net/mana/mana.h
+++ b/include/net/mana/mana.h
@@ -338,7 +338,7 @@ struct mana_rxq {
        /* MUST BE THE LAST MEMBER:
         * Each receive buffer has an associated mana_recv_buf_oob.
         */
-       struct mana_recv_buf_oob rx_oobs[];
+       struct mana_recv_buf_oob rx_oobs[] __counted_by(num_rx_buf);
 };
 
 struct mana_tx_qp {