Merge branch 'for-3.4' of git://linux-nfs.org/~bfields/linux

Pull nfsd changes from Bruce Fields:

Highlights:
 - Benny Halevy and Tigran Mkrtchyan implemented some more 4.1 features,
   moving us closer to a complete 4.1 implementation.
 - Bernd Schubert fixed a long-standing problem with readdir cookies on
   ext2/3/4.
 - Jeff Layton performed a long-overdue overhaul of the server reboot
   recovery code which will allow us to deprecate the current code (a
   rather unusual user of the vfs), and give us some needed flexibility
   for further improvements.
 - Like the client, we now support numeric uid's and gid's in the
   auth_sys case, allowing easier upgrades from NFSv2/v3 to v4.x.

Plus miscellaneous bugfixes and cleanup.

Thanks to everyone!

There are also some delegation fixes waiting on vfs review that I
suppose will have to wait for 3.5.  With that done I think we'll finally
turn off the "EXPERIMENTAL" dependency for v4 (though that's mostly
symbolic as it's been on by default in distro's for a while).

And the list of 4.1 todo's should be achievable for 3.5 as well:

   http://wiki.linux-nfs.org/wiki/index.php/Server_4.0_and_4.1_issues

though we may still want a bit more experience with it before turning it
on by default.

* 'for-3.4' of git://linux-nfs.org/~bfields/linux: (55 commits)
  nfsd: only register cld pipe notifier when CONFIG_NFSD_V4 is enabled
  nfsd4: use auth_unix unconditionally on backchannel
  nfsd: fix NULL pointer dereference in cld_pipe_downcall
  nfsd4: memory corruption in numeric_name_to_id()
  sunrpc: skip portmap calls on sessions backchannel
  nfsd4: allow numeric idmapping
  nfsd: don't allow legacy client tracker init for anything but init_net
  nfsd: add notifier to handle mount/unmount of rpc_pipefs sb
  nfsd: add the infrastructure to handle the cld upcall
  nfsd: add a header describing upcall to nfsdcld
  nfsd: add a per-net-namespace struct for nfsd
  sunrpc: create nfsd dir in rpc_pipefs
  nfsd: add nfsd4_client_tracking_ops struct and a way to set it
  nfsd: convert nfs4_client->cl_cb_flags to a generic flags field
  NFSD: Fix nfs4_verifier memory alignment
  NFSD: Fix warnings when NFSD_DEBUG is not defined
  nfsd: vfs_llseek() with 32 or 64 bit offsets (hashes)
  nfsd: rename 'int access' to 'int may_flags' in nfsd_open()
  ext4: return 32/64-bit dir name hash according to usage type
  fs: add new FMODE flags: FMODE_32bithash and FMODE_64bithash
  ...

1 files changed, 49 insertions, 4 deletions

diff --git a/fs/nfsd/nfs4idmap.c b/fs/nfsd/nfs4idmap.c
index 94096273cd6c..322d11ce06a4 100644
--- a/fs/nfsd/nfs4idmap.c
+++ b/fs/nfsd/nfs4idmap.c
@@ -41,6 +41,14 @@
 #include "nfsd.h"
 
 /*
+ * Turn off idmapping when using AUTH_SYS.
+ */
+static bool nfs4_disable_idmapping = true;
+module_param(nfs4_disable_idmapping, bool, 0644);
+MODULE_PARM_DESC(nfs4_disable_idmapping,
+		"Turn off server's NFSv4 idmapping when using 'sec=sys'");
+
+/*
  * Cache entry
  */
 
@@ -561,28 +569,65 @@ idmap_id_to_name(struct svc_rqst *rqstp, int type, uid_t id, char *name)
 	return ret;
 }
 
+static bool
+numeric_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, uid_t *id)
+{
+	int ret;
+	char buf[11];
+
+	if (namelen + 1 > sizeof(buf))
+		/* too long to represent a 32-bit id: */
+		return false;
+	/* Just to make sure it's null-terminated: */
+	memcpy(buf, name, namelen);
+	buf[namelen] = '\0';
+	ret = kstrtouint(name, 10, id);
+	return ret == 0;
+}
+
+static __be32
+do_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, uid_t *id)
+{
+	if (nfs4_disable_idmapping && rqstp->rq_flavor < RPC_AUTH_GSS)
+		if (numeric_name_to_id(rqstp, type, name, namelen, id))
+			return 0;
+		/*
+		 * otherwise, fall through and try idmapping, for
+		 * backwards compatibility with clients sending names:
+		 */
+	return idmap_name_to_id(rqstp, type, name, namelen, id);
+}
+
+static int
+do_id_to_name(struct svc_rqst *rqstp, int type, uid_t id, char *name)
+{
+	if (nfs4_disable_idmapping && rqstp->rq_flavor < RPC_AUTH_GSS)
+		return sprintf(name, "%u", id);
+	return idmap_id_to_name(rqstp, type, id, name);
+}
+
 __be32
 nfsd_map_name_to_uid(struct svc_rqst *rqstp, const char *name, size_t namelen,
 		__u32 *id)
 {
-	return idmap_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, id);
+	return do_name_to_id(rqstp, IDMAP_TYPE_USER, name, namelen, id);
 }
 
 __be32
 nfsd_map_name_to_gid(struct svc_rqst *rqstp, const char *name, size_t namelen,
 		__u32 *id)
 {
-	return idmap_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, id);
+	return do_name_to_id(rqstp, IDMAP_TYPE_GROUP, name, namelen, id);
 }
 
 int
 nfsd_map_uid_to_name(struct svc_rqst *rqstp, __u32 id, char *name)
 {
-	return idmap_id_to_name(rqstp, IDMAP_TYPE_USER, id, name);
+	return do_id_to_name(rqstp, IDMAP_TYPE_USER, id, name);
 }
 
 int
 nfsd_map_gid_to_name(struct svc_rqst *rqstp, __u32 id, char *name)
 {
-	return idmap_id_to_name(rqstp, IDMAP_TYPE_GROUP, id, name);
+	return do_id_to_name(rqstp, IDMAP_TYPE_GROUP, id, name);
 }