netdev - [PATCH net 2/2] tsnep: Fix XDP_RING_NEED

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20240123200918.61219-3-gerhard@engleder-embedded.com>
Date: Tue, 23 Jan 2024 21:09:18 +0100
From: Gerhard Engleder <gerhard@...leder-embedded.com>
To: netdev@...r.kernel.org,
	bpf@...r.kernel.org
Cc: davem@...emloft.net,
	kuba@...nel.org,
	edumazet@...gle.com,
	pabeni@...hat.com,
	bjorn@...nel.org,
	magnus.karlsson@...el.com,
	maciej.fijalkowski@...el.com,
	jonathan.lemon@...il.com,
	Gerhard Engleder <gerhard@...leder-embedded.com>
Subject: [PATCH net 2/2] tsnep: Fix XDP_RING_NEED_WAKEUP for empty fill ring

The fill ring of the XDP socket may contain not enough buffers to
completey fill the RX queue during socket creation. In this case the
flag XDP_RING_NEED_WAKEUP is not set as this flag is only set if the RX
queue is not completely filled during polling.

Set XDP_RING_NEED_WAKEUP flag also if RX queue is not completely filled
during XDP socket creation.

Fixes: 3fc2333933fd ("tsnep: Add XDP socket zero-copy RX support")
Signed-off-by: Gerhard Engleder <gerhard@...leder-embedded.com>
---
 drivers/net/ethernet/engleder/tsnep_main.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/net/ethernet/engleder/tsnep_main.c b/drivers/net/ethernet/engleder/tsnep_main.c
index d380a407e175..ae0b8b37b9bf 100644
--- a/drivers/net/ethernet/engleder/tsnep_main.c
+++ b/drivers/net/ethernet/engleder/tsnep_main.c
@@ -1764,6 +1764,19 @@ static void tsnep_rx_reopen_xsk(struct tsnep_rx *rx)
 			allocated--;
 		}
 	}
+
+	/* set need wakeup flag immediately if ring is not filled completely,
+	 * first polling would be too late as need wakeup signalisation would
+	 * be delayed for an indefinite time
+	 */
+	if (xsk_uses_need_wakeup(rx->xsk_pool)) {
+		int desc_available = tsnep_rx_desc_available(rx);
+
+		if (desc_available)
+			xsk_set_rx_need_wakeup(rx->xsk_pool);
+		else
+			xsk_clear_rx_need_wakeup(rx->xsk_pool);
+	}
 }
 
 static bool tsnep_pending(struct tsnep_queue *queue)
-- 
2.39.2