Re: [PATCH] net: atm: Fix potential Spectre v1 vulnerabilities

[Gustavo A. R. Silva]

On 4/16/19 11:02 PM, David Miller wrote:
> From: "Gustavo A. R. Silva" <gustavo@xxxxxxxxxxxxxx>
> Date: Mon, 15 Apr 2019 15:57:23 -0500
> 
>> arg is controlled by user-space, hence leading to a potential
>> exploitation of the Spectre variant 1 vulnerability.
>>
>> This issue was detected with the help of Smatch:
>>
>> net/atm/lec.c:715 lec_mcast_attach() warn: potential spectre issue 'dev_lec' [r] (local cap)
>>
>> Fix this by sanitizing arg before using it to index dev_lec.
>>
>> Notice that given that speculation windows are large, the policy is
>> to kill the speculation on the first load and not worry if it can be
>> completed with a dependent load/store [1].
>>
>> [1] https://lore.kernel.org/lkml/20180423164740.GY17484@xxxxxxxxxxxxxx/
>>
>> Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
> 
> Applied and queued up for -stable.
> 

Thank you, Dave.

--
Gustavo