* [PATCH net] net: nixge: fix potential memory leak in nixge_start_xmit()
@ 2022-11-14 8:55 Zhang Changzhong
2022-11-14 10:40 ` Francois Romieu
0 siblings, 1 reply; 5+ messages in thread
From: Zhang Changzhong @ 2022-11-14 8:55 UTC (permalink / raw)
To: David S. Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni,
Moritz Fischer
Cc: Zhang Changzhong, netdev, linux-kernel
The nixge_start_xmit() returns NETDEV_TX_OK but does not free skb on two
error handling cases, which can lead to memory leak.
To fix this, return NETDEV_TX_BUSY in case of nixge_check_tx_bd_space()
fails and add dev_kfree_skb_any() in case of dma_map_single() fails.
Fixes: 492caffa8a1a ("net: ethernet: nixge: Add support for National Instruments XGE netdev")
Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>
---
drivers/net/ethernet/ni/nixge.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/ni/nixge.c b/drivers/net/ethernet/ni/nixge.c
index 19d043b593cc..b9091f9bbc77 100644
--- a/drivers/net/ethernet/ni/nixge.c
+++ b/drivers/net/ethernet/ni/nixge.c
@@ -521,13 +521,15 @@ static netdev_tx_t nixge_start_xmit(struct sk_buff *skb,
if (nixge_check_tx_bd_space(priv, num_frag)) {
if (!netif_queue_stopped(ndev))
netif_stop_queue(ndev);
- return NETDEV_TX_OK;
+ return NETDEV_TX_BUSY;
}
cur_phys = dma_map_single(ndev->dev.parent, skb->data,
skb_headlen(skb), DMA_TO_DEVICE);
- if (dma_mapping_error(ndev->dev.parent, cur_phys))
+ if (dma_mapping_error(ndev->dev.parent, cur_phys)) {
+ dev_kfree_skb_any(skb);
goto drop;
+ }
nixge_hw_dma_bd_set_phys(cur_p, cur_phys);
cur_p->cntrl = skb_headlen(skb) | XAXIDMA_BD_CTRL_TXSOF_MASK;
--
2.31.1
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [PATCH net] net: nixge: fix potential memory leak in nixge_start_xmit()
2022-11-14 8:55 [PATCH net] net: nixge: fix potential memory leak in nixge_start_xmit() Zhang Changzhong
@ 2022-11-14 10:40 ` Francois Romieu
2022-11-15 13:20 ` Zhang Changzhong
0 siblings, 1 reply; 5+ messages in thread
From: Francois Romieu @ 2022-11-14 10:40 UTC (permalink / raw)
To: Zhang Changzhong
Cc: David S. Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni,
Moritz Fischer, netdev, linux-kernel
Zhang Changzhong <zhangchangzhong@huawei.com> :
> The nixge_start_xmit() returns NETDEV_TX_OK but does not free skb on two
> error handling cases, which can lead to memory leak.
>
> To fix this, return NETDEV_TX_BUSY in case of nixge_check_tx_bd_space()
> fails and add dev_kfree_skb_any() in case of dma_map_single() fails.
This patch merge two unrelated changes. Please split.
> Fixes: 492caffa8a1a ("net: ethernet: nixge: Add support for National Instruments XGE netdev")
> Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>
> ---
> drivers/net/ethernet/ni/nixge.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ethernet/ni/nixge.c b/drivers/net/ethernet/ni/nixge.c
> index 19d043b593cc..b9091f9bbc77 100644
> --- a/drivers/net/ethernet/ni/nixge.c
> +++ b/drivers/net/ethernet/ni/nixge.c
> @@ -521,13 +521,15 @@ static netdev_tx_t nixge_start_xmit(struct sk_buff *skb,
> if (nixge_check_tx_bd_space(priv, num_frag)) {
> if (!netif_queue_stopped(ndev))
> netif_stop_queue(ndev);
> - return NETDEV_TX_OK;
> + return NETDEV_TX_BUSY;
> }
The driver should probably check the available room before returning
from hard_start_xmit and turn the check above unlikely().
Btw there is no lock and the Tx completion is irq driven: the driver
is racy. :o(
--
Ueimor
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH net] net: nixge: fix potential memory leak in nixge_start_xmit()
2022-11-14 10:40 ` Francois Romieu
@ 2022-11-15 13:20 ` Zhang Changzhong
2022-11-16 22:36 ` Saeed Mahameed
0 siblings, 1 reply; 5+ messages in thread
From: Zhang Changzhong @ 2022-11-15 13:20 UTC (permalink / raw)
To: Francois Romieu
Cc: David S. Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni,
Moritz Fischer, netdev, linux-kernel
On 2022/11/14 18:40, Francois Romieu wrote:
> Zhang Changzhong <zhangchangzhong@huawei.com> :
>> The nixge_start_xmit() returns NETDEV_TX_OK but does not free skb on two
>> error handling cases, which can lead to memory leak.
>>
>> To fix this, return NETDEV_TX_BUSY in case of nixge_check_tx_bd_space()
>> fails and add dev_kfree_skb_any() in case of dma_map_single() fails.
>
> This patch merge two unrelated changes. Please split.
>
>> Fixes: 492caffa8a1a ("net: ethernet: nixge: Add support for National Instruments XGE netdev")
>> Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>
>> ---
>> drivers/net/ethernet/ni/nixge.c | 6 ++++--
>> 1 file changed, 4 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/ni/nixge.c b/drivers/net/ethernet/ni/nixge.c
>> index 19d043b593cc..b9091f9bbc77 100644
>> --- a/drivers/net/ethernet/ni/nixge.c
>> +++ b/drivers/net/ethernet/ni/nixge.c
>> @@ -521,13 +521,15 @@ static netdev_tx_t nixge_start_xmit(struct sk_buff *skb,
>> if (nixge_check_tx_bd_space(priv, num_frag)) {
>> if (!netif_queue_stopped(ndev))
>> netif_stop_queue(ndev);
>> - return NETDEV_TX_OK;
>> + return NETDEV_TX_BUSY;
>> }
>
> The driver should probably check the available room before returning
> from hard_start_xmit and turn the check above unlikely().
>
> Btw there is no lock and the Tx completion is irq driven: the driver
> is racy. :o(
>
Hi Francois,
Thanks for you review. I'll make v2 according to your suggestion.
Changzhong
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH net] net: nixge: fix potential memory leak in nixge_start_xmit()
2022-11-15 13:20 ` Zhang Changzhong
@ 2022-11-16 22:36 ` Saeed Mahameed
2022-11-17 3:04 ` Zhang Changzhong
0 siblings, 1 reply; 5+ messages in thread
From: Saeed Mahameed @ 2022-11-16 22:36 UTC (permalink / raw)
To: Zhang Changzhong
Cc: Francois Romieu, David S. Miller, Eric Dumazet, Jakub Kicinski,
Paolo Abeni, Moritz Fischer, netdev, linux-kernel
On 15 Nov 21:20, Zhang Changzhong wrote:
>On 2022/11/14 18:40, Francois Romieu wrote:
>> Zhang Changzhong <zhangchangzhong@huawei.com> :
>>> The nixge_start_xmit() returns NETDEV_TX_OK but does not free skb on two
>>> error handling cases, which can lead to memory leak.
>>>
>>> To fix this, return NETDEV_TX_BUSY in case of nixge_check_tx_bd_space()
>>> fails and add dev_kfree_skb_any() in case of dma_map_single() fails.
>>
>> This patch merge two unrelated changes. Please split.
>>
>>> Fixes: 492caffa8a1a ("net: ethernet: nixge: Add support for National Instruments XGE netdev")
>>> Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>
>>> ---
>>> drivers/net/ethernet/ni/nixge.c | 6 ++++--
>>> 1 file changed, 4 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/net/ethernet/ni/nixge.c b/drivers/net/ethernet/ni/nixge.c
>>> index 19d043b593cc..b9091f9bbc77 100644
>>> --- a/drivers/net/ethernet/ni/nixge.c
>>> +++ b/drivers/net/ethernet/ni/nixge.c
>>> @@ -521,13 +521,15 @@ static netdev_tx_t nixge_start_xmit(struct sk_buff *skb,
>>> if (nixge_check_tx_bd_space(priv, num_frag)) {
>>> if (!netif_queue_stopped(ndev))
>>> netif_stop_queue(ndev);
>>> - return NETDEV_TX_OK;
>>> + return NETDEV_TX_BUSY;
>>> }
>>
>> The driver should probably check the available room before returning
>> from hard_start_xmit and turn the check above unlikely().
>>
>> Btw there is no lock and the Tx completion is irq driven: the driver
>> is racy. :o(
>>
>
>Hi Francois,
>
>Thanks for you review. I'll make v2 according to your suggestion.
>
you will probably need to check out: Transmit path guidelines:
https://www.kernel.org/doc/Documentation/networking/driver.rst
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH net] net: nixge: fix potential memory leak in nixge_start_xmit()
2022-11-16 22:36 ` Saeed Mahameed
@ 2022-11-17 3:04 ` Zhang Changzhong
0 siblings, 0 replies; 5+ messages in thread
From: Zhang Changzhong @ 2022-11-17 3:04 UTC (permalink / raw)
To: Saeed Mahameed
Cc: Francois Romieu, David S. Miller, Eric Dumazet, Jakub Kicinski,
Paolo Abeni, Moritz Fischer, netdev, linux-kernel
On 2022/11/17 6:36, Saeed Mahameed wrote:
> On 15 Nov 21:20, Zhang Changzhong wrote:
>> On 2022/11/14 18:40, Francois Romieu wrote:
>>> Zhang Changzhong <zhangchangzhong@huawei.com> :
>>>> The nixge_start_xmit() returns NETDEV_TX_OK but does not free skb on two
>>>> error handling cases, which can lead to memory leak.
>>>>
>>>> To fix this, return NETDEV_TX_BUSY in case of nixge_check_tx_bd_space()
>>>> fails and add dev_kfree_skb_any() in case of dma_map_single() fails.
>>>
>>> This patch merge two unrelated changes. Please split.
>>>
>>>> Fixes: 492caffa8a1a ("net: ethernet: nixge: Add support for National Instruments XGE netdev")
>>>> Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>
>>>> ---
>>>> drivers/net/ethernet/ni/nixge.c | 6 ++++--
>>>> 1 file changed, 4 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/drivers/net/ethernet/ni/nixge.c b/drivers/net/ethernet/ni/nixge.c
>>>> index 19d043b593cc..b9091f9bbc77 100644
>>>> --- a/drivers/net/ethernet/ni/nixge.c
>>>> +++ b/drivers/net/ethernet/ni/nixge.c
>>>> @@ -521,13 +521,15 @@ static netdev_tx_t nixge_start_xmit(struct sk_buff *skb,
>>>> if (nixge_check_tx_bd_space(priv, num_frag)) {
>>>> if (!netif_queue_stopped(ndev))
>>>> netif_stop_queue(ndev);
>>>> - return NETDEV_TX_OK;
>>>> + return NETDEV_TX_BUSY;
>>>> }
>>>
>>> The driver should probably check the available room before returning
>>> from hard_start_xmit and turn the check above unlikely().
>>>
>>> Btw there is no lock and the Tx completion is irq driven: the driver
>>> is racy. :o(
>>>
>>
>> Hi Francois,
>>
>> Thanks for you review. I'll make v2 according to your suggestion.
>>
>
> you will probably need to check out: Transmit path guidelines:
> https://www.kernel.org/doc/Documentation/networking/driver.rst
>
Thank! This document is very helpful.
> .
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2022-11-17 3:04 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
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2022-11-14 8:55 [PATCH net] net: nixge: fix potential memory leak in nixge_start_xmit() Zhang Changzhong
2022-11-14 10:40 ` Francois Romieu
2022-11-15 13:20 ` Zhang Changzhong
2022-11-16 22:36 ` Saeed Mahameed
2022-11-17 3:04 ` Zhang Changzhong
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