Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Subject: Re: [PATCH] vdpa/mlx5: Fix erroneous null pointer checks
To:     Alex Dewar <alex.dewar90@gmail.com>,
        "Michael S. Tsirkin" <mst@redhat.com>,
        Parav Pandit <parav@mellanox.com>,
        Eli Cohen <eli@mellanox.com>,
        virtualization@lists.linux-foundation.org,
        linux-kernel@vger.kernel.org
References: <20200806191849.82189-1-alex.dewar90@gmail.com>
From:   Jason Wang <jasowang@redhat.com>
Message-ID: <a1fb552a-bd5c-d7a2-7eae-d787cc61ec73@redhat.com>
Date:   Fri, 7 Aug 2020 11:37:25 +0800
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101
 Thunderbird/68.10.0
MIME-Version: 1.0
In-Reply-To: <20200806191849.82189-1-alex.dewar90@gmail.com>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 8bit
Content-Language: en-US
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk


On 2020/8/7 上午3:18, Alex Dewar wrote:
> In alloc_inout() in net/mlx5_vnet.c, there are a few places where memory
> is allocated to *in and *out, but only the values of in and out are
> null-checked (i.e. there is a missing dereference). Fix this.
>
> Addresses-Coverity: ("CID 1496603: (REVERSE_INULL)")
> Fixes: 1a86b377aa21 ("vdpa/mlx5: Add VDPA driver for supported mlx5 devices")
> Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>


Acked-by: Jason Wang <jasowang@redhat.com>


> ---
>   drivers/vdpa/mlx5/net/mlx5_vnet.c | 8 ++++----
>   1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> index 3ec44a4f0e45..bcb6600c2839 100644
> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> @@ -867,7 +867,7 @@ static void alloc_inout(struct mlx5_vdpa_net *ndev, int cmd, void **in, int *inl
>   		*outlen = MLX5_ST_SZ_BYTES(qp_2rst_out);
>   		*in = kzalloc(*inlen, GFP_KERNEL);
>   		*out = kzalloc(*outlen, GFP_KERNEL);
> -		if (!in || !out)
> +		if (!*in || !*out)
>   			goto outerr;
>   
>   		MLX5_SET(qp_2rst_in, *in, opcode, cmd);
> @@ -879,7 +879,7 @@ static void alloc_inout(struct mlx5_vdpa_net *ndev, int cmd, void **in, int *inl
>   		*outlen = MLX5_ST_SZ_BYTES(rst2init_qp_out);
>   		*in = kzalloc(*inlen, GFP_KERNEL);
>   		*out = kzalloc(MLX5_ST_SZ_BYTES(rst2init_qp_out), GFP_KERNEL);
> -		if (!in || !out)
> +		if (!*in || !*out)
>   			goto outerr;
>   
>   		MLX5_SET(rst2init_qp_in, *in, opcode, cmd);
> @@ -896,7 +896,7 @@ static void alloc_inout(struct mlx5_vdpa_net *ndev, int cmd, void **in, int *inl
>   		*outlen = MLX5_ST_SZ_BYTES(init2rtr_qp_out);
>   		*in = kzalloc(*inlen, GFP_KERNEL);
>   		*out = kzalloc(MLX5_ST_SZ_BYTES(init2rtr_qp_out), GFP_KERNEL);
> -		if (!in || !out)
> +		if (!*in || !*out)
>   			goto outerr;
>   
>   		MLX5_SET(init2rtr_qp_in, *in, opcode, cmd);
> @@ -914,7 +914,7 @@ static void alloc_inout(struct mlx5_vdpa_net *ndev, int cmd, void **in, int *inl
>   		*outlen = MLX5_ST_SZ_BYTES(rtr2rts_qp_out);
>   		*in = kzalloc(*inlen, GFP_KERNEL);
>   		*out = kzalloc(MLX5_ST_SZ_BYTES(rtr2rts_qp_out), GFP_KERNEL);
> -		if (!in || !out)
> +		if (!*in || !*out)
>   			goto outerr;
>   
>   		MLX5_SET(rtr2rts_qp_in, *in, opcode, cmd);