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From:   Kees Cook <keescook@chromium.org>
To:     Jakub Kicinski <kuba@kernel.org>
Cc:     Kees Cook <keescook@chromium.org>,
        Pravin B Shelar <pshelar@ovn.org>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>, netdev@vger.kernel.org,
        dev@openvswitch.org, Jamal Hadi Salim <jhs@mojatatu.com>,
        David Ahern <dsahern@kernel.org>,
        Martin KaFai Lau <martin.lau@kernel.org>,
        "Gustavo A. R. Silva" <gustavoars@kernel.org>,
        Alexei Starovoitov <ast@kernel.org>,
        Yisen Zhuang <yisen.zhuang@huawei.com>,
        Salil Mehta <salil.mehta@huawei.com>,
        Claudiu Manoil <claudiu.manoil@nxp.com>,
        Vladimir Oltean <vladimir.oltean@nxp.com>,
        "K. Y. Srinivasan" <kys@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
        Wei Liu <wei.liu@kernel.org>, Dexuan Cui <decui@microsoft.com>,
        Long Li <longli@microsoft.com>,
        Ajay Sharma <sharmaajay@microsoft.com>,
        Alex Elder <elder@kernel.org>,
        Shaokun Zhang <zhangshaokun@hisilicon.com>,
        Cong Wang <xiyou.wangcong@gmail.com>,
        Jiri Pirko <jiri@resnulli.us>,
        Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Tom Rix <trix@redhat.com>, Simon Horman <horms@kernel.org>,
        linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org,
        linux-rdma@vger.kernel.org, linux-parisc@vger.kernel.org,
        llvm@lists.linux.dev, linux-hardening@vger.kernel.org
Subject: [PATCH 10/14] net: openvswitch: Annotate struct dp_meter_instance with __counted_by
Date:   Fri, 22 Sep 2023 10:28:52 -0700
Message-Id: <20230922172858.3822653-10-keescook@chromium.org>
In-Reply-To: <20230922172449.work.906-kees@kernel.org>
References: <20230922172449.work.906-kees@kernel.org>
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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 dp_meter_instance.

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

Cc: Pravin B Shelar <pshelar@ovn.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: netdev@vger.kernel.org
Cc: dev@openvswitch.org
Signed-off-by: Kees Cook <keescook@chromium.org>
---
 net/openvswitch/meter.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/openvswitch/meter.h b/net/openvswitch/meter.h
index 0c33889a8515..013de694221f 100644
--- a/net/openvswitch/meter.h
+++ b/net/openvswitch/meter.h
@@ -45,7 +45,7 @@ struct dp_meter {
 struct dp_meter_instance {
 	struct rcu_head rcu;
 	u32 n_meters;
-	struct dp_meter __rcu *dp_meters[];
+	struct dp_meter __rcu *dp_meters[] __counted_by(n_meters);
 };
 
 struct dp_meter_table {
-- 
2.34.1