qubes-linux-kernel/xsa155-linux-xsa155-0006-xen-scsiback-safely-copy-requests.patch
2015-12-17 07:48:52 +01:00

38 lines
1.1 KiB
Diff

From 89739c14c72e5c1626a5cd5e09cbb2efeaadb6d8 Mon Sep 17 00:00:00 2001
From: David Vrabel <david.vrabel@citrix.com>
Date: Mon, 16 Nov 2015 18:02:32 +0000
Subject: [PATCH 6/7] xen-scsiback: safely copy requests
The copy of the ring request was lacking a following barrier(),
potentially allowing the compiler to optimize the copy away.
Use RING_COPY_REQUEST() to ensure the request is copied to local
memory.
This is part of XSA155.
CC: stable@vger.kernel.org
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
drivers/xen/xen-scsiback.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/xen/xen-scsiback.c b/drivers/xen/xen-scsiback.c
index 43bcae8..ad4eb10 100644
--- a/drivers/xen/xen-scsiback.c
+++ b/drivers/xen/xen-scsiback.c
@@ -726,7 +726,7 @@ static int scsiback_do_cmd_fn(struct vscsibk_info *info)
if (!pending_req)
return 1;
- ring_req = *RING_GET_REQUEST(ring, rc);
+ RING_COPY_REQUEST(ring, rc, &ring_req);
ring->req_cons = ++rc;
err = prepare_pending_reqs(info, &ring_req, pending_req);
--
2.1.0