2 files changed, 46 insertions, 16 deletions

diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index afb292cd797d..53ed8d3f8897 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -1353,6 +1353,7 @@ gss_stringify_acceptor(struct rpc_cred *cred)
         char *string = NULL;
         struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
         struct gss_cl_ctx *ctx;
+        unsigned int len;
         struct xdr_netobj *acceptor;
 
         rcu_read_lock();
@@ -1360,15 +1361,39 @@ gss_stringify_acceptor(struct rpc_cred *cred)
         if (!ctx)
                 goto out;
 
-        acceptor = &ctx->gc_acceptor;
+        len = ctx->gc_acceptor.len;
+        rcu_read_unlock();
 
         /* no point if there's no string */
-        if (!acceptor->len)
-                goto out;
-
-        string = kmalloc(acceptor->len + 1, GFP_KERNEL);
+        if (!len)
+                return NULL;
+realloc:
+        string = kmalloc(len + 1, GFP_KERNEL);
         if (!string)
+                return NULL;
+
+        rcu_read_lock();
+        ctx = rcu_dereference(gss_cred->gc_ctx);
+
+        /* did the ctx disappear or was it replaced by one with no acceptor? */
+        if (!ctx || !ctx->gc_acceptor.len) {
+                kfree(string);
+                string = NULL;
                 goto out;
+        }
+
+        acceptor = &ctx->gc_acceptor;
+
+        /*
+         * Did we find a new acceptor that's longer than the original? Allocate
+         * a longer buffer and try again.
+         */
+        if (len < acceptor->len) {
+                len = acceptor->len;
+                rcu_read_unlock();
+                kfree(string);
+                goto realloc;
+        }
 
         memcpy(string, acceptor->data, acceptor->len);
         string[acceptor->len] = '\0';
diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index 3f959c681885..f9c052d508f0 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -1019,17 +1019,12 @@ static int receive_cb_reply(struct svc_sock *svsk, struct svc_rqst *rqstp)
         xid = *p++;
         calldir = *p;
 
-        if (bc_xprt)
-                req = xprt_lookup_rqst(bc_xprt, xid);
-
-        if (!req) {
-                printk(KERN_NOTICE
-                        "%s: Got unrecognized reply: "
-                        "calldir 0x%x xpt_bc_xprt %p xid %08x\n",
-                        __func__, ntohl(calldir),
-                        bc_xprt, ntohl(xid));
+        if (!bc_xprt)
                 return -EAGAIN;
-        }
+        spin_lock_bh(&bc_xprt->transport_lock);
+        req = xprt_lookup_rqst(bc_xprt, xid);
+        if (!req)
+                goto unlock_notfound;
 
         memcpy(&req->rq_private_buf, &req->rq_rcv_buf, sizeof(struct xdr_buf));
         /*
@@ -1040,11 +1035,21 @@ static int receive_cb_reply(struct svc_sock *svsk, struct svc_rqst *rqstp)
         dst = &req->rq_private_buf.head[0];
         src = &rqstp->rq_arg.head[0];
         if (dst->iov_len < src->iov_len)
-                return -EAGAIN; /* whatever; just giving up. */
+                goto unlock_eagain; /* whatever; just giving up. */
         memcpy(dst->iov_base, src->iov_base, src->iov_len);
         xprt_complete_rqst(req->rq_task, rqstp->rq_arg.len);
         rqstp->rq_arg.len = 0;
+        spin_unlock_bh(&bc_xprt->transport_lock);
         return 0;
+unlock_notfound:
+        printk(KERN_NOTICE
+                "%s: Got unrecognized reply: "
+                "calldir 0x%x xpt_bc_xprt %p xid %08x\n",
+                __func__, ntohl(calldir),
+                bc_xprt, ntohl(xid));
+unlock_eagain:
+        spin_unlock_bh(&bc_xprt->transport_lock);
+        return -EAGAIN;
 }
 
 static int copy_pages_to_kvecs(struct kvec *vec, struct page **pages, int len)