[PATCH 1/1] iw_cxgb4: check return value of alloc_skb

[PATCH 1/1] iw_cxgb4: check return value of alloc_skb

[Pan Bian]

Function alloc_skb() will return a NULL pointer when there is no enough
memory. However, the return value of alloc_skb() is directly used
without validation in function send_fw_pass_open_req(). This patches
checks the return value of alloc_skb() against NULL.

Signed-off-by: Pan Bian <bianpan2016@163.com>
---
 drivers/infiniband/hw/cxgb4/cm.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/infiniband/hw/cxgb4/cm.c b/drivers/infiniband/hw/cxgb4/cm.c
index 03a1b0e..196969c 100644
--- a/drivers/infiniband/hw/cxgb4/cm.c
+++ b/drivers/infiniband/hw/cxgb4/cm.c
@@ -3800,6 +3800,8 @@ static void send_fw_pass_open_req(struct c4iw_dev *dev, struct sk_buff *skb,
 	int ret;
 
 	req_skb = alloc_skb(sizeof(struct fw_ofld_connection_wr), GFP_KERNEL);
+	if (!req_skb)
+		return;
 	req = (struct fw_ofld_connection_wr *)__skb_put(req_skb, sizeof(*req));
 	memset(req, 0, sizeof(*req));
 	req->op_compl = htonl(WR_OP_V(FW_OFLD_CONNECTION_WR) | FW_WR_COMPL_F);
-- 
1.9.1

Re: [PATCH 1/1] iw_cxgb4: check return value of alloc_skb

[Leon Romanovsky]

[-- Attachment #1: Type: text/plain, Size: 1230 bytes --]

On Sun, Apr 23, 2017 at 05:09:11PM +0800, Pan Bian wrote:
> Function alloc_skb() will return a NULL pointer when there is no enough
> memory. However, the return value of alloc_skb() is directly used
> without validation in function send_fw_pass_open_req(). This patches
> checks the return value of alloc_skb() against NULL.
>
> Signed-off-by: Pan Bian <bianpan2016@163.com>
> ---
>  drivers/infiniband/hw/cxgb4/cm.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/drivers/infiniband/hw/cxgb4/cm.c b/drivers/infiniband/hw/cxgb4/cm.c
> index 03a1b0e..196969c 100644
> --- a/drivers/infiniband/hw/cxgb4/cm.c
> +++ b/drivers/infiniband/hw/cxgb4/cm.c
> @@ -3800,6 +3800,8 @@ static void send_fw_pass_open_req(struct c4iw_dev *dev, struct sk_buff *skb,
>  	int ret;
>
>  	req_skb = alloc_skb(sizeof(struct fw_ofld_connection_wr), GFP_KERNEL);
> +	if (!req_skb)
> +		return;

The check is right, but the outcome is unpredictable. The function
send_fw_pass_open_req() doesn't return any error and caller doesn't check
it.

>  	req = (struct fw_ofld_connection_wr *)__skb_put(req_skb, sizeof(*req));
>  	memset(req, 0, sizeof(*req));
>  	req->op_compl = htonl(WR_OP_V(FW_OFLD_CONNECTION_WR) | FW_WR_COMPL_F);
> --
> 1.9.1
>
>

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

Re: [PATCH 1/1] iw_cxgb4: check return value of alloc_skb

[Doug Ledford]

On Sun, 2017-04-23 at 17:09 +0800, Pan Bian wrote:
> Function alloc_skb() will return a NULL pointer when there is no
> enough
> memory. However, the return value of alloc_skb() is directly used
> without validation in function send_fw_pass_open_req(). This patches
> checks the return value of alloc_skb() against NULL.
> 
> Signed-off-by: Pan Bian <bianpan2016@163.com>

Thanks, applied.

-- 
Doug Ledford <dledford@redhat.com>
    GPG KeyID: B826A3330E572FDD
   
Key fingerprint = AE6B 1BDA 122B 23B4 265B  1274 B826 A333 0E57 2FDD