2018-06-11 08:43:28

by Zhouyang Jia

Subject: [PATCH] net: cxgb3: add error handling for some functions

When sysfs_create_group or alloc_skb fails, the lack of error-handling
code may cause unexpected results.

This patch adds error-handling code after the functions.

Signed-off-by: Zhouyang Jia <[email protected]>
---
drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c b/drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c
index 2edfdbd..bb51b7e 100644
--- a/drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c
+++ b/drivers/net/ethernet/chelsio/cxgb3/cxgb3_main.c
@@ -545,6 +545,8 @@ static int init_tp_parity(struct adapter *adap)
if (skb == adap->nofail_skb) {
i = await_mgmt_replies(adap, cnt, 16 + 2048 + 2048 + 1);
adap->nofail_skb = alloc_skb(sizeof(*greq), GFP_KERNEL);
+ if (!adap->nofail_skb)
+ goto alloc_skb_fail;
}

t3_tp_set_offload_mode(adap, 0);
@@ -3362,6 +3364,10 @@ static int init_one(struct pci_dev *pdev, const struct pci_device_id *ent)

err = sysfs_create_group(&adapter->port[0]->dev.kobj,
&cxgb3_attr_group);
+ if (err) {
+ dev_err(&pdev->dev, "cannot create sysfs group\n");
+ goto out_free_dev;
+ }

print_port_info(adapter, ai);
return 0;
--
2.7.4

2018-06-11 21:52:58

by David Miller

Subject: Re: [PATCH] net: cxgb3: add error handling for some functions

From: Zhouyang Jia <[email protected]>
Date: Mon, 11 Jun 2018 16:42:26 +0800

> When sysfs_create_group or alloc_skb fails, the lack of error-handling
> code may cause unexpected results.
>
> This patch adds error-handling code after the functions.
>
> Signed-off-by: Zhouyang Jia <[email protected]>

The ->nofail_skb handling is perfectly fine.

It is a backup SKB, meant to handle alloc_skb() failures for the
primary 'skb' allocation the _next_ time this function is called.

Even if the ->nofail_skb allocation fails, the primary operation
done by init_tp_parity() has succeeeded and we should return
success.

All of the code in this function is perfectly prepared to handle
the case where ->nofail_skb is NULL.