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

Jakub Kicinski
2025-09-14T18:53:10Z

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

> 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)