Re: [PATCHv4]Checks for Null value in function *get_skub

From: Nick Krause
Date: Mon Jun 16 2014 - 11:45:12 EST


Can we close this bug or is it still a issue as we can'
return NULL from kfree or kfree_skb. Here is the bug
ID 44631 I would close it if we are done with the bug
otherwise I think there are no other issues with
allocating a skb,
Cheers Nick

On Mon, Jun 16, 2014 at 11:37 AM, Nick Krause <xerofoify@xxxxxxxxx> wrote:
> Signed-off-by: Nicholas Krause <xerofoify@xxxxxxxxx>
> ---
> drivers/infiniband/hw/cxgb4/
> cm.c | 8 +++-----
> 1 file changed, 3 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/infiniband/hw/cxgb4/cm.c b/drivers/infiniband/hw/cxgb4/cm.c
> index f9477e2..2d56983 100644
> --- a/drivers/infiniband/hw/cxgb4/cm.c
> +++ b/drivers/infiniband/hw/cxgb4/cm.c
> @@ -340,15 +340,13 @@ static int status2errno(int status)
> */
> static struct sk_buff *get_skb(struct sk_buff *skb, int len, gfp_t gfp)
> {
> if (skb && !skb_is_nonlinear(skb) && !skb_cloned(skb)) {
> skb_trim(skb, 0);
> skb_get(skb);
> skb_reset_transport_header(skb);
> } else {
> + if (skb)
> /* NULL is ignored */.
> + kfree_skb (skb);
> skb = alloc_skb(len, gfp);
> }
> t4_set_arp_err_handler(skb, NULL, NULL);
>
> On Mon, Jun 16, 2014 at 11:30 AM, Steve Wise
> <swise@xxxxxxxxxxxxxxxxxxxxx> wrote:
>> On 6/16/2014 10:25 AM, Nicholas Krause wrote:
>>>
>>> Signed-off-by: Nicholas Krause <xerofoify@xxxxxxxxx>
>>> ---
>>> drivers/infiniband/hw/cxgb4/cm.c | 8 +++-----
>>> 1 file changed, 3 insertions(+), 5 deletions(-)
>>>
>>> diff --git a/drivers/infiniband/hw/cxgb4/cm.c
>>> b/drivers/infiniband/hw/cxgb4/cm.c
>>> index f9477e2..2d56983 100644
>>> --- a/drivers/infiniband/hw/cxgb4/cm.c
>>> +++ b/drivers/infiniband/hw/cxgb4/cm.c
>>> @@ -340,15 +340,13 @@ static int status2errno(int status)
>>> */
>>> static struct sk_buff *get_skb(struct sk_buff *skb, int len, gfp_t gfp)
>>> {
>>> if (skb && !skb_is_nonlinear(skb) && !skb_cloned(skb)) {
>>> skb_trim(skb, 0);
>>> skb_get(skb);
>>> skb_reset_transport_header(skb);
>>> } else {
>>> + if (skb)
>>> + kfree_skb (skb);
>>> skb = alloc_skb(len, gfp);
>>> }
>>> t4_set_arp_err_handler(skb, NULL, NULL);
>>
>>
>> Can you change the comment? This patch is now fixing a potential skb leak.
>> Also, kfree_sb() will ignore NULL ptrs, so we could just always call it.
>> But I'd add a comment like /* NULL is ignored */.
>>
>> Thanks,
>>
>> Steve.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/