Re: [PATCH for-next] RDMA/rxe - Respond to skb_clone failure in rxe_recv.c

From: Zhu Yanjun <zyjzyj2000@gmail.com>
To: Bob Pearson <rpearsonhpe@gmail.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>,
	colin.king@canonical.com, linux-rdma@vger.kernel.org,
	Bob Pearson <rpearson@hpe.com>
Subject: Re: [PATCH for-next] RDMA/rxe - Respond to skb_clone failure in rxe_recv.c
Date: Wed, 14 Oct 2020 08:39:46 +0800	[thread overview]
Message-ID: <CAD=hENfGR=nLqZNON0=whxDFooG5E+Eq-ggDjrvN+6M+3F7G7w@mail.gmail.com> (raw)
In-Reply-To: <20201013184236.5231-1-rpearson@hpe.com>

On Wed, Oct 14, 2020 at 2:44 AM Bob Pearson <rpearsonhpe@gmail.com> wrote:
>
> If skb_clone is unable to allocate memory for a new
> sk_buff this is not detected by the current code.
>
> Check for a NULL return and continue. This is similar to
> other errors in this loop over QPs attached to the multicast address
> and consistent with the unreliable UD transport.
>
> Fixes: e7ec96fc7932f ("RDMA/rxe: Fix skb lifetime in rxe_rcv_mcast_pkt()")

Addresses-Coverity-ID: 1497804: Null pointer dereferences (NULL_RETURNS)

Thanks
Zhu Yanjun

> Signed-off-by: Bob Pearson <rpearson@hpe.com>
> ---
>  drivers/infiniband/sw/rxe/rxe_recv.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/drivers/infiniband/sw/rxe/rxe_recv.c b/drivers/infiniband/sw/rxe/rxe_recv.c
> index 11f3daf20768..c9984a28eecc 100644
> --- a/drivers/infiniband/sw/rxe/rxe_recv.c
> +++ b/drivers/infiniband/sw/rxe/rxe_recv.c
> @@ -271,6 +271,9 @@ static void rxe_rcv_mcast_pkt(struct rxe_dev *rxe, struct sk_buff *skb)
>                 else
>                         per_qp_skb = skb;
>
> +               if (unlikely(!per_qp_skb))
> +                       continue;
> +
>                 per_qp_pkt = SKB_TO_PKT(per_qp_skb);
>                 per_qp_pkt->qp = qp;
>                 rxe_add_ref(qp);
> --
> 2.25.1
>