Re: [PATCH v3] net: xfrm: Add '_rcu' tag for rcu protected pointer in netns_xfrm

[Eric Dumazet <eric.dumazet@gmail.com>]

On 03/19/2019 08:15 AM, Steffen Klassert wrote:
> On Mon, Mar 18, 2019 at 10:22:46AM -0700, Eric Dumazet wrote:
>>
>>
>> On 03/11/2019 03:10 AM, Steffen Klassert wrote:
>>> On Wed, Mar 06, 2019 at 08:54:08PM -0500, Su Yanjun wrote:
>>>> For rcu protected pointers, we'd better add '__rcu' for them.
>>>>
>>>> Once added '__rcu' tag for rcu protected pointer, the sparse tool reports
>>>> warnings.
>>>>
>>>> net/xfrm/xfrm_user.c:1198:39: sparse:    expected struct sock *sk
>>>> net/xfrm/xfrm_user.c:1198:39: sparse:    got struct sock [noderef] <asn:4> *nlsk
>>>> [...]
>>>>
>>>> So introduce a new wrapper function of nlmsg_unicast  to handle type
>>>> conversions.
>>>>
>>>> This patch also fixes a direct access of a rcu protected socket.
>>>>
>>>> Fixes: be33690d8fcf("[XFRM]: Fix aevent related crash")
>>>> Signed-off-by: Su Yanjun <suyj.fnst@cn.fujitsu.com>
>>>
>>> Patch applied, thanks!
>>>
>>
>> Has this patch ever been tested ?
> 
> I had this on your testing system and it did
> not complain. But maybe my testcases did not
> trigger that codepath. Su, can you answer
> on Eric question?
> 

I can release four syzbot reports if you want.