Re: [PATCH net 2/3] net: tls: Cancel RX async resync request on rdc_delta overflow

Shahar Shitrit
2025-09-22T07:19:01Z

On 14/09/2025 21:53, Jakub Kicinski wrote:
> On Wed, 10 Sep 2025 09:47:40 +0300 Tariq Toukan wrote:
>> When a netdev issues an RX async resync request, the TLS module
>> increments rcd_delta for each new record that arrives. This tracks
>> how far the current record is from the point where synchronization
>> was lost.
>>
>> When rcd_delta reaches its threshold, it indicates that the device
>> response is either excessively delayed or unlikely to arrive at all
>> (at that point, tcp_sn may have wrapped around, so a match would no
>> longer be valid anyway).
>>
>> Previous patch introduced tls_offload_rx_resync_async_request_cancel()
>> to explicitly cancel resync requests when a device response failure
>> is detected.
>>
>> This patch adds a final safeguard: cancel the async resync request when
>> rcd_delta crosses its threshold, as reaching this point implies that
>> earlier cancellation did not occur.
>
> Missing a Fixes tag
Will add
>
>> diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
>> index f672a62a9a52..56c14f1647a4 100644
>> --- a/net/tls/tls_device.c
>> +++ b/net/tls/tls_device.c
>> @@ -721,8 +721,11 @@ tls_device_rx_resync_async(struct tls_offload_resync_async *resync_async,
>> /* shouldn't get to wraparound:
>> * too long in async stage, something bad happened
>> */
>> - if (WARN_ON_ONCE(resync_async->rcd_delta == USHRT_MAX))
>> + if (WARN_ON_ONCE(resync_async->rcd_delta == USHRT_MAX)) {
>> + /* cancel resync request */
>> + atomic64_set(&resync_async->req, 0);
>
> we should probably use the helper added by the previous patch (I'd
> probably squash them TBH)
It's not trivial to use the helper here, since we don't have the socket.
We can maybe add another inner helper that performs the 0 setting and
call it here and inside the helper introduced in previous patch.