Re: [PATCH 07/14] net: mana: Annotate struct mana_rxq with __counted_by

From: Gustavo A. R. Silva
Date: Sat Sep 23 2023 - 08:22:48 EST




On 9/22/23 11:28, Kees Cook wrote:
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@xxxxxxxxxxxxx>
Cc: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
Cc: Wei Liu <wei.liu@xxxxxxxxxx>
Cc: Dexuan Cui <decui@xxxxxxxxxxxxx>
Cc: Long Li <longli@xxxxxxxxxxxxx>
Cc: Ajay Sharma <sharmaajay@xxxxxxxxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Eric Dumazet <edumazet@xxxxxxxxxx>
Cc: Jakub Kicinski <kuba@xxxxxxxxxx>
Cc: Paolo Abeni <pabeni@xxxxxxxxxx>
Cc: linux-hyperv@xxxxxxxxxxxxxxx
Cc: linux-rdma@xxxxxxxxxxxxxxx
Cc: netdev@xxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>


Reviewed-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>

Thanks
--
Gustavo

---
include/net/mana/mana.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/net/mana/mana.h b/include/net/mana/mana.h
index 9f70b4332238..38441be68592 100644
--- 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 {