Re: [PATCH] usb: gadget: eem: fix wrong eem header operation

[linyyuan@codeaurora.org]

On 2021-06-04 18:50, Greg KH wrote:
> On Thu, Jun 03, 2021 at 11:09:47PM +0800, Linyu Yuan wrote:
>> From: Linyu Yuan <linyyuan@codeaurora.com>
>> 
>> when skb_clone() or skb_copy_expand() fail,
> 
> How can these calls fail?  If they do, what is the overall system
> health?
indeed skb_copy_expand() fail on system when it have low continuous 
memory region
when using bigger MTU.
> 
>> it should pull skb with lengh indicated by header,
>> or not it will read network data and check it as header.
>> 
>> Signed-off-by: Linyu Yuan <linyyuan@codeaurora.com>
>> ---
>>  drivers/usb/gadget/function/f_eem.c | 4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> What commit does this fix?  Should it go to stable kernels?  If so, how
> far back?
this change can't avoid all system memory issue which cause skb failure,
but i help reduce driver parse wrong network data which may consume too 
much CPU time.

i will cc stable@vger.kernel.org on V2. i think it can apply to all 
active stable branch,
from 4.4 to 5.10.

> 
> And any reason you didn't use scripts/get_maintainer.pl for who to send
> your patch to?
thanks very much, i will follow your suggestion and provide a V2.
> 
> thanks,
> 
> greg k-h