1 files changed, 168 insertions, 91 deletions

diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index acf88ae..e2e7914 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -168,6 +168,8 @@ int nfsd_mountpoint(struct dentry *dentry, struct svc_export *exp)
 {
 	if (d_mountpoint(dentry))
 		return 1;
+	if (nfsd4_is_junction(dentry))
+		return 1;
 	if (!(exp->ex_flags & NFSEXP_V4ROOT))
 		return 0;
 	return dentry->d_inode != NULL;
@@ -295,41 +297,12 @@ commit_metadata(struct svc_fh *fhp)
 }
 
 /*
- * Set various file attributes.
- * N.B. After this call fhp needs an fh_put
+ * Go over the attributes and take care of the small differences between
+ * NFS semantics and what Linux expects.
  */
-__be32
-nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
-	     int check_guard, time_t guardtime)
+static void
+nfsd_sanitize_attrs(struct inode *inode, struct iattr *iap)
 {
-	struct dentry	*dentry;
-	struct inode	*inode;
-	int		accmode = NFSD_MAY_SATTR;
-	int		ftype = 0;
-	__be32		err;
-	int		host_err;
-	int		size_change = 0;
-
-	if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_SIZE))
-		accmode |= NFSD_MAY_WRITE|NFSD_MAY_OWNER_OVERRIDE;
-	if (iap->ia_valid & ATTR_SIZE)
-		ftype = S_IFREG;
-
-	/* Get inode */
-	err = fh_verify(rqstp, fhp, ftype, accmode);
-	if (err)
-		goto out;
-
-	dentry = fhp->fh_dentry;
-	inode = dentry->d_inode;
-
-	/* Ignore any mode updates on symlinks */
-	if (S_ISLNK(inode->i_mode))
-		iap->ia_valid &= ~ATTR_MODE;
-
-	if (!iap->ia_valid)
-		goto out;
-
 	/*
 	 * NFSv2 does not differentiate between "set-[ac]time-to-now"
 	 * which only requires access, and "set-[ac]time-to-X" which
@@ -339,8 +312,7 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
 	 * convert to "set to now" instead of "set to explicit time"
 	 *
 	 * We only call inode_change_ok as the last test as technically
-	 * it is not an interface that we should be using.  It is only
-	 * valid if the filesystem does not define it's own i_op->setattr.
+	 * it is not an interface that we should be using.
 	 */
 #define BOTH_TIME_SET (ATTR_ATIME_SET | ATTR_MTIME_SET)
 #define	MAX_TOUCH_TIME_ERROR (30*60)
@@ -366,30 +338,6 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
 			iap->ia_valid &= ~BOTH_TIME_SET;
 		}
 	}
-	    
-	/*
-	 * The size case is special.
-	 * It changes the file as well as the attributes.
-	 */
-	if (iap->ia_valid & ATTR_SIZE) {
-		if (iap->ia_size < inode->i_size) {
-			err = nfsd_permission(rqstp, fhp->fh_export, dentry,
-					NFSD_MAY_TRUNC|NFSD_MAY_OWNER_OVERRIDE);
-			if (err)
-				goto out;
-		}
-
-		host_err = get_write_access(inode);
-		if (host_err)
-			goto out_nfserr;
-
-		size_change = 1;
-		host_err = locks_verify_truncate(inode, NULL, iap->ia_size);
-		if (host_err) {
-			put_write_access(inode);
-			goto out_nfserr;
-		}
-	}
 
 	/* sanitize the mode change */
 	if (iap->ia_valid & ATTR_MODE) {
@@ -412,32 +360,120 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
 			iap->ia_valid |= (ATTR_KILL_SUID | ATTR_KILL_SGID);
 		}
 	}
+}
 
-	/* Change the attributes. */
+static __be32
+nfsd_get_write_access(struct svc_rqst *rqstp, struct svc_fh *fhp,
+		struct iattr *iap)
+{
+	struct inode *inode = fhp->fh_dentry->d_inode;
+	int host_err;
 
-	iap->ia_valid |= ATTR_CTIME;
+	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.
+ */
+__be32
+nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
+	     int check_guard, time_t guardtime)
+{
+	struct dentry	*dentry;
+	struct inode	*inode;
+	int		accmode = NFSD_MAY_SATTR;
+	int		ftype = 0;
+	__be32		err;
+	int		host_err;
+	bool		get_write_count;
+	int		size_change = 0;
 
-	err = nfserr_notsync;
-	if (!check_guard || guardtime == inode->i_ctime.tv_sec) {
-		host_err = nfsd_break_lease(inode);
+	if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_SIZE))
+		accmode |= NFSD_MAY_WRITE|NFSD_MAY_OWNER_OVERRIDE;
+	if (iap->ia_valid & ATTR_SIZE)
+		ftype = S_IFREG;
+
+	/* Callers that do fh_verify should do the fh_want_write: */
+	get_write_count = !fhp->fh_dentry;
+
+	/* Get inode */
+	err = fh_verify(rqstp, fhp, ftype, accmode);
+	if (err)
+		goto out;
+	if (get_write_count) {
+		host_err = fh_want_write(fhp);
 		if (host_err)
-			goto out_nfserr;
-		fh_lock(fhp);
+			return nfserrno(host_err);
+	}
 
-		host_err = notify_change(dentry, iap);
-		err = nfserrno(host_err);
-		fh_unlock(fhp);
+	dentry = fhp->fh_dentry;
+	inode = dentry->d_inode;
+
+	/* Ignore any mode updates on symlinks */
+	if (S_ISLNK(inode->i_mode))
+		iap->ia_valid &= ~ATTR_MODE;
+
+	if (!iap->ia_valid)
+		goto out;
+
+	nfsd_sanitize_attrs(inode, iap);
+
+	/*
+	 * The size case is special, it changes the file in addition to the
+	 * attributes.
+	 */
+	if (iap->ia_valid & ATTR_SIZE) {
+		err = nfsd_get_write_access(rqstp, fhp, iap);
+		if (err)
+			goto out;
+		size_change = 1;
 	}
+
+	iap->ia_valid |= ATTR_CTIME;
+
+	if (check_guard && guardtime != inode->i_ctime.tv_sec) {
+		err = nfserr_notsync;
+		goto out_put_write_access;
+	}
+
+	host_err = nfsd_break_lease(inode);
+	if (host_err)
+		goto out_put_write_access_nfserror;
+
+	fh_lock(fhp);
+	host_err = notify_change(dentry, iap);
+	fh_unlock(fhp);
+
+out_put_write_access_nfserror:
+	err = nfserrno(host_err);
+out_put_write_access:
 	if (size_change)
 		put_write_access(inode);
 	if (!err)
 		commit_metadata(fhp);
 out:
 	return err;
-
-out_nfserr:
-	err = nfserrno(host_err);
-	goto out;
 }
 
 #if defined(CONFIG_NFSD_V2_ACL) || \
@@ -472,6 +508,9 @@ set_nfsv4_acl_one(struct dentry *dentry, struct posix_acl *pacl, char *key)
 	char *buf = NULL;
 	int error = 0;
 
+	if (!pacl)
+		return vfs_setxattr(dentry, key, NULL, 0, 0);
+
 	buflen = posix_acl_xattr_size(pacl->a_count);
 	buf = kmalloc(buflen, GFP_KERNEL);
 	error = -ENOMEM;
@@ -502,7 +541,7 @@ nfsd4_set_nfs4_acl(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	unsigned int flags = 0;
 
 	/* Get inode */
-	error = fh_verify(rqstp, fhp, 0 /* S_IFREG */, NFSD_MAY_SATTR);
+	error = fh_verify(rqstp, fhp, 0, NFSD_MAY_SATTR);
 	if (error)
 		return error;
 
@@ -592,6 +631,22 @@ nfsd4_get_nfs4_acl(struct svc_rqst *rqstp, struct dentry *dentry, struct nfs4_ac
 	return error;
 }
 
+#define NFSD_XATTR_JUNCTION_PREFIX XATTR_TRUSTED_PREFIX "junction."
+#define NFSD_XATTR_JUNCTION_TYPE NFSD_XATTR_JUNCTION_PREFIX "type"
+int nfsd4_is_junction(struct dentry *dentry)
+{
+	struct inode *inode = dentry->d_inode;
+
+	if (inode == NULL)
+		return 0;
+	if (inode->i_mode & S_IXUGO)
+		return 0;
+	if (!(inode->i_mode & S_ISVTX))
+		return 0;
+	if (vfs_getxattr(dentry, NFSD_XATTR_JUNCTION_TYPE, NULL, 0) <= 0)
+		return 0;
+	return 1;
+}
 #endif /* defined(CONFIG_NFSD_V4) */
 
 #ifdef CONFIG_NFSD_V3
@@ -708,12 +763,13 @@ static int nfsd_open_break_lease(struct inode *inode, int access)
 
 /*
  * Open an existing file or directory.
- * The access argument indicates the type of open (read/write/lock)
+ * The may_flags argument indicates the type of open (read/write/lock)
+ * and additional flags.
  * N.B. After this call fhp needs an fh_put
  */
 __be32
 nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
-			int access, struct file **filp)
+			int may_flags, struct file **filp)
 {
 	struct dentry	*dentry;
 	struct inode	*inode;
@@ -728,7 +784,7 @@ nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
 	 * and (hopefully) checked permission - so allow OWNER_OVERRIDE
 	 * in case a chmod has now revoked permission.
 	 */
-	err = fh_verify(rqstp, fhp, type, access | NFSD_MAY_OWNER_OVERRIDE);
+	err = fh_verify(rqstp, fhp, type, may_flags | NFSD_MAY_OWNER_OVERRIDE);
 	if (err)
 		goto out;
 
@@ -739,7 +795,7 @@ nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
 	 * or any access when mandatory locking enabled
 	 */
 	err = nfserr_perm;
-	if (IS_APPEND(inode) && (access & NFSD_MAY_WRITE))
+	if (IS_APPEND(inode) && (may_flags & NFSD_MAY_WRITE))
 		goto out;
 	/*
 	 * We must ignore files (but only files) which might have mandatory
@@ -752,22 +808,30 @@ nfsd_open(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
 	if (!inode->i_fop)
 		goto out;
 
-	host_err = nfsd_open_break_lease(inode, access);
+	host_err = nfsd_open_break_lease(inode, may_flags);
 	if (host_err) /* NOMEM or WOULDBLOCK */
 		goto out_nfserr;
 
-	if (access & NFSD_MAY_WRITE) {
-		if (access & NFSD_MAY_READ)
+	if (may_flags & NFSD_MAY_WRITE) {
+		if (may_flags & NFSD_MAY_READ)
 			flags = O_RDWR|O_LARGEFILE;
 		else
 			flags = O_WRONLY|O_LARGEFILE;
 	}
 	*filp = dentry_open(dget(dentry), mntget(fhp->fh_export->ex_path.mnt),
 			    flags, current_cred());
-	if (IS_ERR(*filp))
+	if (IS_ERR(*filp)) {
 		host_err = PTR_ERR(*filp);
-	else
-		host_err = ima_file_check(*filp, access);
+		*filp = NULL;
+	} else {
+		host_err = ima_file_check(*filp, may_flags);
+
+		if (may_flags & NFSD_MAY_64BIT_COOKIE)
+			(*filp)->f_mode |= FMODE_64BITHASH;
+		else
+			(*filp)->f_mode |= FMODE_32BITHASH;
+	}
+
 out_nfserr:
 	err = nfserrno(host_err);
 out:
@@ -1352,7 +1416,7 @@ __be32
 do_nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
 		char *fname, int flen, struct iattr *iap,
 		struct svc_fh *resfhp, int createmode, u32 *verifier,
-	        int *truncp, int *created)
+	        bool *truncp, bool *created)
 {
 	struct dentry	*dentry, *dchild = NULL;
 	struct inode	*dirp;
@@ -1421,7 +1485,7 @@ do_nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
 		switch (createmode) {
 		case NFS3_CREATE_UNCHECKED:
 			if (! S_ISREG(dchild->d_inode->i_mode))
-				err = nfserr_exist;
+				goto out;
 			else if (truncp) {
 				/* in nfsv4, we need to treat this case a little
 				 * differently.  we don't want to truncate the
@@ -1440,13 +1504,19 @@ do_nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
 		case NFS3_CREATE_EXCLUSIVE:
 			if (   dchild->d_inode->i_mtime.tv_sec == v_mtime
 			    && dchild->d_inode->i_atime.tv_sec == v_atime
-			    && dchild->d_inode->i_size  == 0 )
+			    && dchild->d_inode->i_size  == 0 ) {
+				if (created)
+					*created = 1;
 				break;
+			}
 		case NFS4_CREATE_EXCLUSIVE4_1:
 			if (   dchild->d_inode->i_mtime.tv_sec == v_mtime
 			    && dchild->d_inode->i_atime.tv_sec == v_atime
-			    && dchild->d_inode->i_size  == 0 )
+			    && dchild->d_inode->i_size  == 0 ) {
+				if (created)
+					*created = 1;
 				goto set_attr;
+			}
 			 /* fallthru */
 		case NFS3_CREATE_GUARDED:
 			err = nfserr_exist;
@@ -1632,10 +1702,12 @@ nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp,
 	err = fh_verify(rqstp, ffhp, S_IFDIR, NFSD_MAY_CREATE);
 	if (err)
 		goto out;
-	err = fh_verify(rqstp, tfhp, -S_IFDIR, NFSD_MAY_NOP);
+	err = fh_verify(rqstp, tfhp, 0, NFSD_MAY_NOP);
 	if (err)
 		goto out;
-
+	err = nfserr_isdir;
+	if (S_ISDIR(tfhp->fh_dentry->d_inode->i_mode))
+		goto out;
 	err = nfserr_perm;
 	if (!len)
 		goto out;
@@ -1989,8 +2061,13 @@ nfsd_readdir(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t *offsetp,
 	__be32		err;
 	struct file	*file;
 	loff_t		offset = *offsetp;
+	int             may_flags = NFSD_MAY_READ;
+
+	/* NFSv2 only supports 32 bit cookies */
+	if (rqstp->rq_vers > 2)
+		may_flags |= NFSD_MAY_64BIT_COOKIE;
 
-	err = nfsd_open(rqstp, fhp, S_IFDIR, NFSD_MAY_READ, &file);
+	err = nfsd_open(rqstp, fhp, S_IFDIR, may_flags, &file);
 	if (err)
 		goto out;