[PATCH 10/14] net: openvswitch: Annotate struct dp_meter_instance with __counted_by

From: Kees Cook
Date: Fri Sep 22 2023 - 13:29:38 EST


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@xxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Eric Dumazet <edumazet@xxxxxxxxxx>
Cc: Jakub Kicinski <kuba@xxxxxxxxxx>
Cc: Paolo Abeni <pabeni@xxxxxxxxxx>
Cc: netdev@xxxxxxxxxxxxxxx
Cc: dev@xxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
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