Patch-mainline: never (revert original patch due to kabi)
References: bsc#1179508 XSA-349 CVE-2020-29568
From: Juergen Gross <jgross@suse.com>
Date: Tue, 22 Dec 2020 10:17:23 +0100
Subject: [PATCH] xen: revert Add 'will_handle' callback support in xenbus_watch_path()

Due to kabi changes revert original patch
"xen/xenbus: Add 'will_handle' callback support in xenbus_watch_path()"
(commit 2e85d32b1c865bec703ce0c962221a5e955c52c2 upstream).

The issue will be fixed differently in a followup patch.

Signed-off-by: Juergen Gross <jgross@suse.com>
---
 drivers/block/xen-blkback/xenbus.c | 3 +--
 drivers/net/xen-netback/xenbus.c   | 2 +-
 drivers/xen/xen-pciback/xenbus.c   | 2 +-
 drivers/xen/xenbus/xenbus_client.c | 9 ++-------
 drivers/xen/xenbus/xenbus_probe.c  | 2 +-
 include/xen/xenbus.h               | 6 +-----
 6 files changed, 7 insertions(+), 17 deletions(-)

diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c
index 5e5ec549fb21..e8b9ed31f10e 100644
--- a/drivers/block/xen-blkback/xenbus.c
+++ b/drivers/block/xen-blkback/xenbus.c
@@ -636,8 +636,7 @@ static int xen_blkbk_probe(struct xenbus_device *dev,
 	/* setup back pointer */
 	be->blkif->be = be;
 
-	err = xenbus_watch_pathfmt(dev, &be->backend_watch, NULL,
-				   backend_changed,
+	err = xenbus_watch_pathfmt(dev, &be->backend_watch, backend_changed,
 				   "%s/%s", dev->nodename, "physical-device");
 	if (err)
 		goto fail;
diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c
index 910322b442bd..e46276f8e4a5 100644
--- a/drivers/net/xen-netback/xenbus.c
+++ b/drivers/net/xen-netback/xenbus.c
@@ -1043,7 +1043,7 @@ static void connect(struct backend_info *be)
 	xenvif_carrier_on(be->vif);
 
 	unregister_hotplug_status_watch(be);
-	err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch, NULL,
+	err = xenbus_watch_pathfmt(dev, &be->hotplug_status_watch,
 				   hotplug_status_changed,
 				   "%s/%s", dev->nodename, "hotplug-status");
 	if (!err)
diff --git a/drivers/xen/xen-pciback/xenbus.c b/drivers/xen/xen-pciback/xenbus.c
index c7647586948e..3814b44bf1f7 100644
--- a/drivers/xen/xen-pciback/xenbus.c
+++ b/drivers/xen/xen-pciback/xenbus.c
@@ -687,7 +687,7 @@ static int xen_pcibk_xenbus_probe(struct xenbus_device *dev,
 
 	/* watch the backend node for backend configuration information */
 	err = xenbus_watch_path(dev, dev->nodename, &pdev->be_watch,
-				NULL, xen_pcibk_be_watch);
+				xen_pcibk_be_watch);
 	if (err)
 		goto out;
 
diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
index 3797ab09428d..17602ba6d5b2 100644
--- a/drivers/xen/xenbus/xenbus_client.c
+++ b/drivers/xen/xenbus/xenbus_client.c
@@ -114,22 +114,19 @@ EXPORT_SYMBOL_GPL(xenbus_strstate);
  */
 int xenbus_watch_path(struct xenbus_device *dev, const char *path,
 		      struct xenbus_watch *watch,
-		      bool (*will_handle)(struct xenbus_watch *,
-					  const char *, const char *),
 		      void (*callback)(struct xenbus_watch *,
 				       const char *, const char *))
 {
 	int err;
 
 	watch->node = path;
-	watch->will_handle = will_handle;
+	watch->will_handle = NULL;
 	watch->callback = callback;
 
 	err = register_xenbus_watch(watch);
 
 	if (err) {
 		watch->node = NULL;
-		watch->will_handle = NULL;
 		watch->callback = NULL;
 		xenbus_dev_fatal(dev, err, "adding watch on %s", path);
 	}
@@ -156,8 +153,6 @@ EXPORT_SYMBOL_GPL(xenbus_watch_path);
  */
 int xenbus_watch_pathfmt(struct xenbus_device *dev,
 			 struct xenbus_watch *watch,
-			 bool (*will_handle)(struct xenbus_watch *,
-					const char *, const char *),
 			 void (*callback)(struct xenbus_watch *,
 					  const char *, const char *),
 			 const char *pathfmt, ...)
@@ -174,7 +169,7 @@ int xenbus_watch_pathfmt(struct xenbus_device *dev,
 		xenbus_dev_fatal(dev, -ENOMEM, "allocating path for watch");
 		return -ENOMEM;
 	}
-	err = xenbus_watch_path(dev, path, watch, will_handle, callback);
+	err = xenbus_watch_path(dev, path, watch, callback);
 
 	if (err)
 		kfree(path);
diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c
index ed03d7e5c0dc..74888cacd0b0 100644
--- a/drivers/xen/xenbus/xenbus_probe.c
+++ b/drivers/xen/xenbus/xenbus_probe.c
@@ -136,7 +136,7 @@ static int watch_otherend(struct xenbus_device *dev)
 		container_of(dev->dev.bus, struct xen_bus_type, bus);
 
 	return xenbus_watch_pathfmt(dev, &dev->otherend_watch,
-				    NULL, bus->otherend_changed,
+				    bus->otherend_changed,
 				    "%s/%s", dev->otherend, "state");
 }
 
diff --git a/include/xen/xenbus.h b/include/xen/xenbus.h
index de5ae6c6fa0f..55f543fe0bd8 100644
--- a/include/xen/xenbus.h
+++ b/include/xen/xenbus.h
@@ -199,14 +199,10 @@ void xenbus_probe(struct work_struct *);
 
 int xenbus_watch_path(struct xenbus_device *dev, const char *path,
 		      struct xenbus_watch *watch,
-		      bool (*will_handle)(struct xenbus_watch *,
-					  const char *, const char *),
 		      void (*callback)(struct xenbus_watch *,
 				       const char *, const char *));
-__printf(5, 6)
+__printf(4, 5)
 int xenbus_watch_pathfmt(struct xenbus_device *dev, struct xenbus_watch *watch,
-			 bool (*will_handle)(struct xenbus_watch *,
-					     const char *, const char *),
 			 void (*callback)(struct xenbus_watch *,
 					  const char *, const char *),
 			 const char *pathfmt, ...);
-- 
2.26.2