Merge branch 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6

* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
  NFS: don't try to decode GETATTR if DELEGRETURN returned error
  sunrpc: handle allocation errors from __rpc_lookup_create()
  SUNRPC: Fix the return value of rpc_run_bc_task()
  SUNRPC: Fix a use after free bug with the NFSv4.1 backchannel
  SUNRPC: Fix a potential memory leak in auth_gss
  NFS: Prevent another deadlock in nfs_release_page()

9 files changed, 22 insertions, 36 deletions

diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index ae8d02294e46..ae0d92736531 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -491,7 +491,8 @@ static int nfs_release_page(struct page *page, gfp_t gfp)
 {
 	dfprintk(PAGECACHE, "NFS: release_page(%p)\n", page);
 
-	if (gfp & __GFP_WAIT)
+	/* Only do I/O if gfp is a superset of GFP_KERNEL */
+	if ((gfp & GFP_KERNEL) == GFP_KERNEL)
 		nfs_wb_page(page->mapping->host, page);
 	/* If PagePrivate() is set, then the page is not freeable */
 	if (PagePrivate(page))
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 4d338be492cb..dd17713413a5 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -5552,6 +5552,8 @@ static int nfs4_xdr_dec_delegreturn(struct rpc_rqst *rqstp, __be32 *p, struct nf
 	if (status != 0)
 		goto out;
 	status = decode_delegreturn(&xdr);
+	if (status != 0)
+		goto out;
 	decode_getfattr(&xdr, res->fattr, res->server,
 			!RPC_IS_ASYNC(rqstp->rq_task));
 out:
diff --git a/include/linux/sunrpc/bc_xprt.h b/include/linux/sunrpc/bc_xprt.h
index d7152b451e21..7c91260c44a9 100644
--- a/include/linux/sunrpc/bc_xprt.h
+++ b/include/linux/sunrpc/bc_xprt.h
@@ -36,7 +36,6 @@ struct rpc_rqst *xprt_alloc_bc_request(struct rpc_xprt *xprt);
 void xprt_free_bc_request(struct rpc_rqst *req);
 int xprt_setup_backchannel(struct rpc_xprt *, unsigned int min_reqs);
 void xprt_destroy_backchannel(struct rpc_xprt *, int max_reqs);
-void bc_release_request(struct rpc_task *);
 int bc_send(struct rpc_rqst *req);
 
 /*
@@ -59,6 +58,10 @@ static inline int svc_is_backchannel(const struct svc_rqst *rqstp)
 {
 	return 0;
 }
+
+static inline void xprt_free_bc_request(struct rpc_rqst *req)
+{
+}
 #endif /* CONFIG_NFS_V4_1 */
 #endif /* _LINUX_SUNRPC_BC_XPRT_H */
 
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index 0cfccc2a0297..c389ccf6437d 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -1280,9 +1280,8 @@ alloc_enc_pages(struct rpc_rqst *rqstp)
 	rqstp->rq_release_snd_buf = priv_release_snd_buf;
 	return 0;
 out_free:
-	for (i--; i >= 0; i--) {
-		__free_page(rqstp->rq_enc_pages[i]);
-	}
+	rqstp->rq_enc_pages_num = i;
+	priv_release_snd_buf(rqstp);
 out:
 	return -EAGAIN;
 }
diff --git a/net/sunrpc/bc_svc.c b/net/sunrpc/bc_svc.c
index 13f214f53120..f0c05d3311c1 100644
--- a/net/sunrpc/bc_svc.c
+++ b/net/sunrpc/bc_svc.c
@@ -37,21 +37,6 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #define RPCDBG_FACILITY	RPCDBG_SVCDSP
 
-void bc_release_request(struct rpc_task *task)
-{
-	struct rpc_rqst *req = task->tk_rqstp;
-
-	dprintk("RPC:       bc_release_request: task= %p\n", task);
-
-	/*
-	 * Release this request only if it's a backchannel
-	 * preallocated request
-	 */
-	if (!bc_prealloc(req))
-		return;
-	xprt_free_bc_request(req);
-}
-
 /* Empty callback ops */
 static const struct rpc_call_ops nfs41_callback_ops = {
 };
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 154034b675bd..19c9983d5360 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -659,6 +659,7 @@ struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
 	task = rpc_new_task(&task_setup_data);
 	if (!task) {
 		xprt_free_bc_request(req);
+		task = ERR_PTR(-ENOMEM);
 		goto out;
 	}
 	task->tk_rqstp = req;
diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index 8d63f8fd29b7..20e30c6f8355 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -587,6 +587,8 @@ static struct dentry *__rpc_lookup_create_exclusive(struct dentry *parent,
 	struct dentry *dentry;
 
 	dentry = __rpc_lookup_create(parent, name);
+	if (IS_ERR(dentry))
+		return dentry;
 	if (dentry->d_inode == NULL)
 		return dentry;
 	dput(dentry);
diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c
index 469de292c23c..42f09ade0044 100644
--- a/net/sunrpc/xprt.c
+++ b/net/sunrpc/xprt.c
@@ -46,6 +46,7 @@
 
 #include <linux/sunrpc/clnt.h>
 #include <linux/sunrpc/metrics.h>
+#include <linux/sunrpc/bc_xprt.h>
 
 #include "sunrpc.h"
 
@@ -1032,21 +1033,16 @@ void xprt_release(struct rpc_task *task)
 	if (req->rq_release_snd_buf)
 		req->rq_release_snd_buf(req);
 
-	/*
-	 * Early exit if this is a backchannel preallocated request.
-	 * There is no need to have it added to the RPC slot list.
-	 */
-	if (is_bc_request)
-		return;
-
-	memset(req, 0, sizeof(*req));	/* mark unused */
-
 	dprintk("RPC: %5u release request %p\n", task->tk_pid, req);
+	if (likely(!is_bc_request)) {
+		memset(req, 0, sizeof(*req));	/* mark unused */
 
-	spin_lock(&xprt->reserve_lock);
-	list_add(&req->rq_list, &xprt->free);
-	rpc_wake_up_next(&xprt->backlog);
-	spin_unlock(&xprt->reserve_lock);
+		spin_lock(&xprt->reserve_lock);
+		list_add(&req->rq_list, &xprt->free);
+		rpc_wake_up_next(&xprt->backlog);
+		spin_unlock(&xprt->reserve_lock);
+	} else
+		xprt_free_bc_request(req);
 }
 
 /**
diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index e4839c07c913..9847c30b5001 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -2251,9 +2251,6 @@ static struct rpc_xprt_ops xs_tcp_ops = {
 	.buf_free		= rpc_free,
 	.send_request		= xs_tcp_send_request,
 	.set_retrans_timeout	= xprt_set_retrans_timeout_def,
-#if defined(CONFIG_NFS_V4_1)
-	.release_request	= bc_release_request,
-#endif /* CONFIG_NFS_V4_1 */
 	.close			= xs_tcp_close,
 	.destroy		= xs_destroy,
 	.print_stats		= xs_tcp_print_stats,