Re: memory leakage in ncm_wrap_ntb() in USB ncm mode with kernel 5.15

["nanfengwq@xxxxxxxx" <nanfengwq@xxxxxxxx>]

hello:

       In embedded devices with relatively small memory, if the transfer speed of ncm is fast and other programs occupy CPU memory, it is likely that the return value ncm ->skd_tx_data of alloc_skb() is NULL, and the code is likely to enter err. If skb2 is not processed in err, it will cause memory leakage.

Thank you.

---

nanfengwq@xxxxxxxx

 

From: gregkh

Date: 2024-05-19 22:37

To: nanfengwq@xxxxxxxx

CC: balbi; linux-usb; linux-kernel

Subject: Re: memory leakage in ncm_wrap_ntb() in USB ncm mode with kernel 5.15

On Sun, May 19, 2024 at 10:23:10PM +0800, nanfengwq@xxxxxxxx wrote:

> Hello：

> I have discovered a risk of memory leakage in ncm_wrap_ntb() under USB ncm mode in kernel 5.15, and I have fixed it.

> Please help me review it.

>

> If this modification is effective, it can also be integrated into other kernel versions, such as kernel 4.14, and so on.

>

> The logic of a memory leak is as follows:

>

> If the return value skb2 of  package_for_tx() is not NULL, and the return value ncm->skb_tx_data of alloc_skb() is NULL, then the code will go to err, where there is no processing of skb2, resulting in a memory leak in skb2.

>

>

> Thank you.

>

>

>

>

 

 

Hi,

 

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him

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created.  Hopefully you will not take offence and will fix the problem

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