Merge tag 'nfsd-4.10-2' of git://linux-nfs.org/~bfields/linux

Pull nfsd fixes from Bruce Fields:
 "Three more miscellaneous nfsd bugfixes"

* tag 'nfsd-4.10-2' of git://linux-nfs.org/~bfields/linux:
  svcrpc: fix oops in absence of krb5 module
  nfsd: special case truncates some more
  NFSD: Fix a null reference case in find_or_create_lock_stateid()

4 files changed, 50 insertions, 75 deletions

diff --git a/fs/nfsd/nfs4layouts.c b/fs/nfsd/nfs4layouts.c
index 596205d..1fc07a9 100644
--- a/fs/nfsd/nfs4layouts.c
+++ b/fs/nfsd/nfs4layouts.c
@@ -223,10 +223,11 @@ nfsd4_alloc_layout_stateid(struct nfsd4_compound_state *cstate,
 	struct nfs4_layout_stateid *ls;
 	struct nfs4_stid *stp;
 
-	stp = nfs4_alloc_stid(cstate->clp, nfs4_layout_stateid_cache);
+	stp = nfs4_alloc_stid(cstate->clp, nfs4_layout_stateid_cache,
+					nfsd4_free_layout_stateid);
 	if (!stp)
 		return NULL;
-	stp->sc_free = nfsd4_free_layout_stateid;
+
 	get_nfs4_file(fp);
 	stp->sc_file = fp;
 
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 4b4beaa..a0dee8a 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -633,8 +633,8 @@ out:
 	return co;
 }
 
-struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl,
-					 struct kmem_cache *slab)
+struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl, struct kmem_cache *slab,
+				  void (*sc_free)(struct nfs4_stid *))
 {
 	struct nfs4_stid *stid;
 	int new_id;
@@ -650,6 +650,8 @@ struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl,
 	idr_preload_end();
 	if (new_id < 0)
 		goto out_free;
+
+	stid->sc_free = sc_free;
 	stid->sc_client = cl;
 	stid->sc_stateid.si_opaque.so_id = new_id;
 	stid->sc_stateid.si_opaque.so_clid = cl->cl_clientid;
@@ -675,15 +677,12 @@ out_free:
 static struct nfs4_ol_stateid * nfs4_alloc_open_stateid(struct nfs4_client *clp)
 {
 	struct nfs4_stid *stid;
-	struct nfs4_ol_stateid *stp;
 
-	stid = nfs4_alloc_stid(clp, stateid_slab);
+	stid = nfs4_alloc_stid(clp, stateid_slab, nfs4_free_ol_stateid);
 	if (!stid)
 		return NULL;
 
-	stp = openlockstateid(stid);
-	stp->st_stid.sc_free = nfs4_free_ol_stateid;
-	return stp;
+	return openlockstateid(stid);
 }
 
 static void nfs4_free_deleg(struct nfs4_stid *stid)
@@ -781,11 +780,10 @@ alloc_init_deleg(struct nfs4_client *clp, struct svc_fh *current_fh,
 		goto out_dec;
 	if (delegation_blocked(&current_fh->fh_handle))
 		goto out_dec;
-	dp = delegstateid(nfs4_alloc_stid(clp, deleg_slab));
+	dp = delegstateid(nfs4_alloc_stid(clp, deleg_slab, nfs4_free_deleg));
 	if (dp == NULL)
 		goto out_dec;
 
-	dp->dl_stid.sc_free = nfs4_free_deleg;
 	/*
 	 * delegation seqid's are never incremented.  The 4.1 special
 	 * meaning of seqid 0 isn't meaningful, really, but let's avoid
@@ -5580,7 +5578,6 @@ init_lock_stateid(struct nfs4_ol_stateid *stp, struct nfs4_lockowner *lo,
 	stp->st_stateowner = nfs4_get_stateowner(&lo->lo_owner);
 	get_nfs4_file(fp);
 	stp->st_stid.sc_file = fp;
-	stp->st_stid.sc_free = nfs4_free_lock_stateid;
 	stp->st_access_bmap = 0;
 	stp->st_deny_bmap = open_stp->st_deny_bmap;
 	stp->st_openstp = open_stp;
@@ -5623,7 +5620,7 @@ find_or_create_lock_stateid(struct nfs4_lockowner *lo, struct nfs4_file *fi,
 	lst = find_lock_stateid(lo, fi);
 	if (lst == NULL) {
 		spin_unlock(&clp->cl_lock);
-		ns = nfs4_alloc_stid(clp, stateid_slab);
+		ns = nfs4_alloc_stid(clp, stateid_slab, nfs4_free_lock_stateid);
 		if (ns == NULL)
 			return NULL;
 
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index c939936..4516e8b 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -603,8 +603,8 @@ extern __be32 nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
 __be32 nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate,
 		     stateid_t *stateid, unsigned char typemask,
 		     struct nfs4_stid **s, struct nfsd_net *nn);
-struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl,
-		struct kmem_cache *slab);
+struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl, struct kmem_cache *slab,
+				  void (*sc_free)(struct nfs4_stid *));
 void nfs4_unhash_stid(struct nfs4_stid *s);
 void nfs4_put_stid(struct nfs4_stid *s);
 void nfs4_inc_and_copy_stateid(stateid_t *dst, struct nfs4_stid *stid);
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 26c6fdb..ca13236 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -332,37 +332,6 @@ nfsd_sanitize_attrs(struct inode *inode, struct iattr *iap)
 	}
 }
 
-static __be32
-nfsd_get_write_access(struct svc_rqst *rqstp, struct svc_fh *fhp,
-		struct iattr *iap)
-{
-	struct inode *inode = d_inode(fhp->fh_dentry);
-	int host_err;
-
-	if (iap->ia_size < inode->i_size) {
-		__be32 err;
-
-		err = nfsd_permission(rqstp, fhp->fh_export, fhp->fh_dentry,
-				NFSD_MAY_TRUNC | NFSD_MAY_OWNER_OVERRIDE);
-		if (err)
-			return err;
-	}
-
-	host_err = get_write_access(inode);
-	if (host_err)
-		goto out_nfserrno;
-
-	host_err = locks_verify_truncate(inode, NULL, iap->ia_size);
-	if (host_err)
-		goto out_put_write_access;
-	return 0;
-
-out_put_write_access:
-	put_write_access(inode);
-out_nfserrno:
-	return nfserrno(host_err);
-}
-
 /*
  * Set various file attributes.  After this call fhp needs an fh_put.
  */
@@ -377,7 +346,6 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
 	__be32		err;
 	int		host_err;
 	bool		get_write_count;
-	int		size_change = 0;
 
 	if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_SIZE))
 		accmode |= NFSD_MAY_WRITE|NFSD_MAY_OWNER_OVERRIDE;
@@ -390,11 +358,11 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
 	/* Get inode */
 	err = fh_verify(rqstp, fhp, ftype, accmode);
 	if (err)
-		goto out;
+		return err;
 	if (get_write_count) {
 		host_err = fh_want_write(fhp);
 		if (host_err)
-			return nfserrno(host_err);
+			goto out_host_err;
 	}
 
 	dentry = fhp->fh_dentry;
@@ -405,50 +373,59 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
 		iap->ia_valid &= ~ATTR_MODE;
 
 	if (!iap->ia_valid)
-		goto out;
+		return 0;
 
 	nfsd_sanitize_attrs(inode, iap);
 
+	if (check_guard && guardtime != inode->i_ctime.tv_sec)
+		return nfserr_notsync;
+
 	/*
 	 * The size case is special, it changes the file in addition to the
-	 * attributes.
+	 * attributes, and file systems don't expect it to be mixed with
+	 * "random" attribute changes.  We thus split out the size change
+	 * into a separate call for vfs_truncate, and do the rest as a
+	 * a separate setattr call.
 	 */
 	if (iap->ia_valid & ATTR_SIZE) {
-		err = nfsd_get_write_access(rqstp, fhp, iap);
-		if (err)
-			goto out;
-		size_change = 1;
+		struct path path = {
+			.mnt	= fhp->fh_export->ex_path.mnt,
+			.dentry	= dentry,
+		};
+		bool implicit_mtime = false;
 
 		/*
-		 * RFC5661, Section 18.30.4:
-		 *   Changing the size of a file with SETATTR indirectly
-		 *   changes the time_modify and change attributes.
-		 *
-		 * (and similar for the older RFCs)
+		 * vfs_truncate implicity updates the mtime IFF the file size
+		 * actually changes.  Avoid the additional seattr call below if
+		 * the only other attribute that the client sends is the mtime.
 		 */
-		if (iap->ia_size != i_size_read(inode))
-			iap->ia_valid |= ATTR_MTIME;
-	}
+		if (iap->ia_size != i_size_read(inode) &&
+		    ((iap->ia_valid & ~(ATTR_SIZE | ATTR_MTIME)) == 0))
+			implicit_mtime = true;
 
-	iap->ia_valid |= ATTR_CTIME;
+		host_err = vfs_truncate(&path, iap->ia_size);
+		if (host_err)
+			goto out_host_err;
 
-	if (check_guard && guardtime != inode->i_ctime.tv_sec) {
-		err = nfserr_notsync;
-		goto out_put_write_access;
+		iap->ia_valid &= ~ATTR_SIZE;
+		if (implicit_mtime)
+			iap->ia_valid &= ~ATTR_MTIME;
+		if (!iap->ia_valid)
+			goto done;
 	}
 
+	iap->ia_valid |= ATTR_CTIME;
+
 	fh_lock(fhp);
 	host_err = notify_change(dentry, iap, NULL);
 	fh_unlock(fhp);
-	err = nfserrno(host_err);
+	if (host_err)
+		goto out_host_err;
 
-out_put_write_access:
-	if (size_change)
-		put_write_access(inode);
-	if (!err)
-		err = nfserrno(commit_metadata(fhp));
-out:
-	return err;
+done:
+	host_err = commit_metadata(fhp);
+out_host_err:
+	return nfserrno(host_err);
 }
 
 #if defined(CONFIG_NFSD_V4)