From 94a997637c5b562fa0ca44fca1d2cd02ec08236f Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= Date: Wed, 4 Sep 2019 13:49:10 +0200 Subject: [PATCH] xsk: avoid store-tearing when assigning queues MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Use WRITE_ONCE when doing the store of tx, rx, fq, and cq, to avoid potential store-tearing. These members are read outside of the control mutex in the mmap implementation. Acked-by: Jonathan Lemon Fixes: 37b076933a8e ("xsk: add missing write- and data-dependency barrier") Signed-off-by: Björn Töpel Signed-off-by: Daniel Borkmann --- net/xdp/xsk.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c index 187fd157fcff..271d8d3fb11e 100644 --- a/net/xdp/xsk.c +++ b/net/xdp/xsk.c @@ -434,7 +434,7 @@ static int xsk_init_queue(u32 entries, struct xsk_queue **queue, /* Make sure queue is ready before it can be seen by others */ smp_wmb(); - *queue = q; + WRITE_ONCE(*queue, q); return 0; }