Patch "SUNRPC: allow for upcalls for same uid but different gss service" has been added to the 4.7-stable tree

This is a note to let you know that I've just added the patch titled

SUNRPC: allow for upcalls for same uid but different gss service

to the 4.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
sunrpc-allow-for-upcalls-for-same-uid-but-different-gss-service.patch
and it can be found in the queue-4.7 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Olga Kornievskaia <[email protected]>
Date: Wed, 3 Aug 2016 20:19:48 -0400
Subject: SUNRPC: allow for upcalls for same uid but different gss service

From: Olga Kornievskaia <[email protected]>

commit 9130b8dbc6ac20f2dc5846e1647f5b60eafab6e3 upstream.

It's possible to have simultaneous upcalls for the same UIDs but different GSS service. In that case, we need to allow for the upcall to gssd to proceed so that not the same context is used by two different GSS services. Some servers lock the use of context to the GSS service.

---
 net/sunrpc/auth_gss/auth_gss.c |    8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

@@ -340,12 +340,14 @@ gss_release_msg(struct gss_upcall_msg *g
 }
 
 static struct gss_upcall_msg *
-__gss_find_upcall(struct rpc_pipe *pipe, kuid_t uid)
+__gss_find_upcall(struct rpc_pipe *pipe, kuid_t uid, const struct gss_auth *auth)
 {
 	struct gss_upcall_msg *pos;
 	list_for_each_entry(pos, &pipe->in_downcall, list) {
 		if (!uid_eq(pos->uid, uid))
 			continue;
+		if (auth && pos->auth->service != auth->service)
+			continue;
 		atomic_inc(&pos->count);
 		dprintk("RPC:       %s found msg %p\n", __func__, pos);
 		return pos;

@@ -365,7 +367,7 @@ gss_add_msg(struct gss_upcall_msg *gss_m
 	struct gss_upcall_msg *old;
 
 	spin_lock(&pipe->lock);
-	old = __gss_find_upcall(pipe, gss_msg->uid);
+	old = __gss_find_upcall(pipe, gss_msg->uid, gss_msg->auth);
 	if (old == NULL) {
 		atomic_inc(&gss_msg->count);
 		list_add(&gss_msg->list, &pipe->in_downcall);

@@ -714,7 +716,7 @@ gss_pipe_downcall(struct file *filp, con
 	err = -ENOENT;
 	/* Find a matching upcall */
 	spin_lock(&pipe->lock);
-	gss_msg = __gss_find_upcall(pipe, uid);
+	gss_msg = __gss_find_upcall(pipe, uid, NULL);
 	if (gss_msg == NULL) {
 		spin_unlock(&pipe->lock);
 		goto err_put_ctx;

Patches currently in stable-queue which might be from [email protected] are

queue-4.7/sunrpc-allow-for-upcalls-for-same-uid-but-different-gss-service.patch