Merge tag 'nfs-for-5.2-1' of git://git.linux-nfs.org/projects/anna/linux-nfs

Pull NFS client updates from Anna Schumaker:
 "Highlights include:

  Stable bugfixes:
   - Fall back to MDS if no deviceid is found rather than aborting   # v4.11+
   - NFS4: Fix v4.0 client state corruption when mount

  Features:
   - Much improved handling of soft mounts with NFS v4.0:
       - Reduce risk of false positive timeouts
       - Faster failover of reads and writes after a timeout
       - Added a "softerr" mount option to return ETIMEDOUT instead of
         EIO to the application after a timeout
   - Increase number of xprtrdma backchannel requests
   - Add additional xprtrdma tracepoints
   - Improved send completion batching for xprtrdma

  Other bugfixes and cleanups:
   - Return -EINVAL when NFS v4.2 is passed an invalid dedup mode
   - Reduce usage of GFP_ATOMIC pages in SUNRPC
   - Various minor NFS over RDMA cleanups and bugfixes
   - Use the correct container namespace for upcalls
   - Don't share superblocks between user namespaces
   - Various other container fixes
   - Make nfs_match_client() killable to prevent soft lockups
   - Don't mark all open state for recovery when handling recallable
     state revoked flag"

* tag 'nfs-for-5.2-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (69 commits)
  SUNRPC: Rebalance a kref in auth_gss.c
  NFS: Fix a double unlock from nfs_match,get_client
  nfs: pass the correct prototype to read_cache_page
  NFSv4: don't mark all open state for recovery when handling recallable state revoked flag
  SUNRPC: Fix an error code in gss_alloc_msg()
  SUNRPC: task should be exit if encode return EKEYEXPIRED more times
  NFS4: Fix v4.0 client state corruption when mount
  PNFS fallback to MDS if no deviceid found
  NFS: make nfs_match_client killable
  lockd: Store the lockd client credential in struct nlm_host
  NFS: When mounting, don't share filesystems between different user namespaces
  NFS: Convert NFSv2 to use the container user namespace
  NFSv4: Convert the NFS client idmapper to use the container user namespace
  NFS: Convert NFSv3 to use the container user namespace
  SUNRPC: Use namespace of listening daemon in the client AUTH_GSS upcall
  SUNRPC: Use the client user namespace when encoding creds
  NFS: Store the credential of the mount process in the nfs_server
  SUNRPC: Cache cred of process creating the rpc_client
  xprtrdma: Remove stale comment
  xprtrdma: Update comments that reference ib_drain_qp
  ...

net/sunrpc/auth_gss/auth_gss.c

@@ -269,6 +269,7 @@ err:
 struct gss_upcall_msg {
 	refcount_t count;
 	kuid_t	uid;
+	const char *service_name;
 	struct rpc_pipe_msg msg;
 	struct list_head list;
 	struct gss_auth *auth;
@@ -316,6 +317,7 @@ gss_release_msg(struct gss_upcall_msg *gss_msg)
 		gss_put_ctx(gss_msg->ctx);
 	rpc_destroy_wait_queue(&gss_msg->rpc_waitqueue);
 	gss_put_auth(gss_msg->auth);
+	kfree_const(gss_msg->service_name);
 	kfree(gss_msg);
 }
 
@@ -410,9 +412,12 @@ gss_upcall_callback(struct rpc_task *task)
 	gss_release_msg(gss_msg);
 }
 
-static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg)
+static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg,
+			      const struct cred *cred)
 {
-	uid_t uid = from_kuid(&init_user_ns, gss_msg->uid);
+	struct user_namespace *userns = cred->user_ns;
+
+	uid_t uid = from_kuid_munged(userns, gss_msg->uid);
 	memcpy(gss_msg->databuf, &uid, sizeof(uid));
 	gss_msg->msg.data = gss_msg->databuf;
 	gss_msg->msg.len = sizeof(uid);
@@ -420,17 +425,31 @@ static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg)
 	BUILD_BUG_ON(sizeof(uid) > sizeof(gss_msg->databuf));
 }
 
+static ssize_t
+gss_v0_upcall(struct file *file, struct rpc_pipe_msg *msg,
+		char __user *buf, size_t buflen)
+{
+	struct gss_upcall_msg *gss_msg = container_of(msg,
+						      struct gss_upcall_msg,
+						      msg);
+	if (msg->copied == 0)
+		gss_encode_v0_msg(gss_msg, file->f_cred);
+	return rpc_pipe_generic_upcall(file, msg, buf, buflen);
+}
+
 static int gss_encode_v1_msg(struct gss_upcall_msg *gss_msg,
 				const char *service_name,
-				const char *target_name)
+				const char *target_name,
+				const struct cred *cred)
 {
+	struct user_namespace *userns = cred->user_ns;
 	struct gss_api_mech *mech = gss_msg->auth->mech;
 	char *p = gss_msg->databuf;
 	size_t buflen = sizeof(gss_msg->databuf);
 	int len;
 
 	len = scnprintf(p, buflen, "mech=%s uid=%d", mech->gm_name,
-			from_kuid(&init_user_ns, gss_msg->uid));
+			from_kuid_munged(userns, gss_msg->uid));
 	buflen -= len;
 	p += len;
 	gss_msg->msg.len = len;
@@ -491,6 +510,25 @@ out_overflow:
 	return -ENOMEM;
 }
 
+static ssize_t
+gss_v1_upcall(struct file *file, struct rpc_pipe_msg *msg,
+		char __user *buf, size_t buflen)
+{
+	struct gss_upcall_msg *gss_msg = container_of(msg,
+						      struct gss_upcall_msg,
+						      msg);
+	int err;
+	if (msg->copied == 0) {
+		err = gss_encode_v1_msg(gss_msg,
+					gss_msg->service_name,
+					gss_msg->auth->target_name,
+					file->f_cred);
+		if (err)
+			return err;
+	}
+	return rpc_pipe_generic_upcall(file, msg, buf, buflen);
+}
+
 static struct gss_upcall_msg *
 gss_alloc_msg(struct gss_auth *gss_auth,
 		kuid_t uid, const char *service_name)
@@ -513,16 +551,14 @@ gss_alloc_msg(struct gss_auth *gss_auth,
 	refcount_set(&gss_msg->count, 1);
 	gss_msg->uid = uid;
 	gss_msg->auth = gss_auth;
-	switch (vers) {
-	case 0:
-		gss_encode_v0_msg(gss_msg);
-		break;
-	default:
-		err = gss_encode_v1_msg(gss_msg, service_name, gss_auth->target_name);
-		if (err)
-			goto err_put_pipe_version;
-	}
 	kref_get(&gss_auth->kref);
+	if (service_name) {
+		gss_msg->service_name = kstrdup_const(service_name, GFP_NOFS);
+		if (!gss_msg->service_name) {
+			err = -ENOMEM;
+			goto err_put_pipe_version;
+		}
+	}
 	return gss_msg;
 err_put_pipe_version:
 	put_pipe_version(gss_auth->net);
@@ -581,8 +617,8 @@ gss_refresh_upcall(struct rpc_task *task)
 		/* XXX: warning on the first, under the assumption we
 		 * shouldn't normally hit this case on a refresh. */
 		warn_gssd();
-		task->tk_timeout = 15*HZ;
-		rpc_sleep_on(&pipe_version_rpc_waitqueue, task, NULL);
+		rpc_sleep_on_timeout(&pipe_version_rpc_waitqueue,
+				task, NULL, jiffies + (15 * HZ));
 		err = -EAGAIN;
 		goto out;
 	}
@@ -595,7 +631,6 @@ gss_refresh_upcall(struct rpc_task *task)
 	if (gss_cred->gc_upcall != NULL)
 		rpc_sleep_on(&gss_cred->gc_upcall->rpc_waitqueue, task, NULL);
 	else if (gss_msg->ctx == NULL && gss_msg->msg.errno >= 0) {
-		task->tk_timeout = 0;
 		gss_cred->gc_upcall = gss_msg;
 		/* gss_upcall_callback will release the reference to gss_upcall_msg */
 		refcount_inc(&gss_msg->count);
@@ -707,7 +742,7 @@ gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
 		goto err;
 	}
 
-	uid = make_kuid(&init_user_ns, id);
+	uid = make_kuid(current_user_ns(), id);
 	if (!uid_valid(uid)) {
 		err = -EINVAL;
 		goto err;
@@ -2116,7 +2151,7 @@ static const struct rpc_credops gss_nullops = {
 };
 
 static const struct rpc_pipe_ops gss_upcall_ops_v0 = {
-	.upcall		= rpc_pipe_generic_upcall,
+	.upcall		= gss_v0_upcall,
 	.downcall	= gss_pipe_downcall,
 	.destroy_msg	= gss_pipe_destroy_msg,
 	.open_pipe	= gss_pipe_open_v0,
@@ -2124,7 +2159,7 @@ static const struct rpc_pipe_ops gss_upcall_ops_v0 = {
 };
 
 static const struct rpc_pipe_ops gss_upcall_ops_v1 = {
-	.upcall		= rpc_pipe_generic_upcall,
+	.upcall		= gss_v1_upcall,
 	.downcall	= gss_pipe_downcall,
 	.destroy_msg	= gss_pipe_destroy_msg,
 	.open_pipe	= gss_pipe_open_v1,