cifs: account for primary channel in the interface list

The refcounting of server interfaces should account
for the primary channel too. Although this is not
strictly necessary, doing so will account for the primary
channel in DebugData.

Cc: stable@vger.kernel.org
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

1 files changed, 28 insertions, 0 deletions

diff --git a/fs/smb/client/sess.c b/fs/smb/client/sess.c
index 336b64d93e41..e716d046fb5f 100644
--- a/fs/smb/client/sess.c
+++ b/fs/smb/client/sess.c
@@ -303,6 +303,7 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
 	struct cifs_server_iface *iface = NULL;
 	struct cifs_server_iface *old_iface = NULL;
 	struct cifs_server_iface *last_iface = NULL;
+	struct sockaddr_storage ss;
 	int rc = 0;
 
 	spin_lock(&ses->chan_lock);
@@ -321,6 +322,10 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
 	}
 	spin_unlock(&ses->chan_lock);
 
+	spin_lock(&server->srv_lock);
+	ss = server->dstaddr;
+	spin_unlock(&server->srv_lock);
+
 	spin_lock(&ses->iface_lock);
 	if (!ses->iface_count) {
 		spin_unlock(&ses->iface_lock);
@@ -334,6 +339,16 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
 
 	/* then look for a new one */
 	list_for_each_entry(iface, &ses->iface_list, iface_head) {
+		if (!chan_index) {
+			/* if we're trying to get the updated iface for primary channel */
+			if (!cifs_match_ipaddr((struct sockaddr *) &ss,
+					       (struct sockaddr *) &iface->sockaddr))
+				continue;
+
+			kref_get(&iface->refcount);
+			break;
+		}
+
 		/* do not mix rdma and non-rdma interfaces */
 		if (iface->rdma_capable != server->rdma)
 			continue;
@@ -360,6 +375,13 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
 		cifs_dbg(FYI, "unable to find a suitable iface\n");
 	}
 
+	if (!chan_index && !iface) {
+		cifs_dbg(FYI, "unable to get the interface matching: %pIS\n",
+			 &ss);
+		spin_unlock(&ses->iface_lock);
+		return 0;
+	}
+
 	/* now drop the ref to the current iface */
 	if (old_iface && iface) {
 		cifs_dbg(FYI, "replacing iface: %pIS with %pIS\n",
@@ -382,6 +404,12 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
 			old_iface->weight_fulfilled--;
 
 		kref_put(&old_iface->refcount, release_iface);
+	} else if (!chan_index) {
+		/* special case: update interface for primary channel */
+		cifs_dbg(FYI, "referencing primary channel iface: %pIS\n",
+			 &iface->sockaddr);
+		iface->num_channels++;
+		iface->weight_fulfilled++;
 	} else {
 		WARN_ON(!iface);
 		cifs_dbg(FYI, "adding new iface: %pIS\n", &iface->sockaddr);