Merge tag '5.8-rc4-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:
 "Four cifs/smb3 fixes: the three for stable fix problems found recently
  with change notification including a reference count leak"

* tag '5.8-rc4-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: update internal module version number
  cifs: fix reference leak for tlink
  smb3: fix unneeded error message on change notify
  cifs: remove the retry in cifs_poxis_lock_set
  smb3: fix access denied on change notify request to some servers

fs/cifs/cifsfs.h

@@ -156,5 +156,5 @@ extern int cifs_truncate_page(struct address_space *mapping, loff_t from);
 extern const struct export_operations cifs_export_ops;
 #endif /* CONFIG_CIFS_NFSD_EXPORT */
 
-#define CIFS_VERSION   "2.27"
+#define CIFS_VERSION   "2.28"
 #endif				/* _CIFSFS_H */

fs/cifs/file.c

@@ -1149,20 +1149,20 @@ cifs_posix_lock_test(struct file *file, struct file_lock *flock)
 
 /*
  * Set the byte-range lock (posix style). Returns:
- * 1) 0, if we set the lock and don't need to request to the server;
- * 2) 1, if we need to request to the server;
- * 3) <0, if the error occurs while setting the lock.
+ * 1) <0, if the error occurs while setting the lock;
+ * 2) 0, if we set the lock and don't need to request to the server;
+ * 3) FILE_LOCK_DEFERRED, if we will wait for some other file_lock;
+ * 4) FILE_LOCK_DEFERRED + 1, if we need to request to the server.
  */
 static int
 cifs_posix_lock_set(struct file *file, struct file_lock *flock)
 {
 	struct cifsInodeInfo *cinode = CIFS_I(file_inode(file));
-	int rc = 1;
+	int rc = FILE_LOCK_DEFERRED + 1;
 
 	if ((flock->fl_flags & FL_POSIX) == 0)
 		return rc;
 
-try_again:
 	cifs_down_write(&cinode->lock_sem);
 	if (!cinode->can_cache_brlcks) {
 		up_write(&cinode->lock_sem);
@@ -1171,13 +1171,6 @@ cifs_posix_lock_set(struct file *file, struct file_lock *flock)
 
 	rc = posix_lock_file(file, flock, NULL);
 	up_write(&cinode->lock_sem);
-	if (rc == FILE_LOCK_DEFERRED) {
-		rc = wait_event_interruptible(flock->fl_wait,
-					list_empty(&flock->fl_blocked_member));
-		if (!rc)
-			goto try_again;
-		locks_delete_block(flock);
-	}
 	return rc;
 }
 
@@ -1652,7 +1645,7 @@ cifs_setlk(struct file *file, struct file_lock *flock, __u32 type,
 		int posix_lock_type;
 
 		rc = cifs_posix_lock_set(file, flock);
-		if (!rc || rc < 0)
+		if (rc <= FILE_LOCK_DEFERRED)
 			return rc;
 
 		if (type & server->vals->shared_lock_type)

fs/cifs/ioctl.c

@@ -169,6 +169,7 @@ long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
 	unsigned int xid;
 	struct cifsFileInfo *pSMBFile = filep->private_data;
 	struct cifs_tcon *tcon;
+	struct tcon_link *tlink;
 	struct cifs_sb_info *cifs_sb;
 	__u64	ExtAttrBits = 0;
 	__u64   caps;
@@ -307,13 +308,19 @@ long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
 				break;
 			}
 			cifs_sb = CIFS_SB(inode->i_sb);
-			tcon = tlink_tcon(cifs_sb_tlink(cifs_sb));
+			tlink = cifs_sb_tlink(cifs_sb);
+			if (IS_ERR(tlink)) {
+				rc = PTR_ERR(tlink);
+				break;
+			}
+			tcon = tlink_tcon(tlink);
 			if (tcon && tcon->ses->server->ops->notify) {
 				rc = tcon->ses->server->ops->notify(xid,
 						filep, (void __user *)arg);
 				cifs_dbg(FYI, "ioctl notify rc %d\n", rc);
 			} else
 				rc = -EOPNOTSUPP;
+			cifs_put_tlink(tlink);
 			break;
 		default:
 			cifs_dbg(FYI, "unsupported ioctl\n");

fs/cifs/smb2misc.c

@@ -354,9 +354,13 @@ smb2_get_data_area_len(int *off, int *len, struct smb2_sync_hdr *shdr)
 		  ((struct smb2_ioctl_rsp *)shdr)->OutputCount);
 		break;
 	case SMB2_CHANGE_NOTIFY:
+		*off = le16_to_cpu(
+		  ((struct smb2_change_notify_rsp *)shdr)->OutputBufferOffset);
+		*len = le32_to_cpu(
+		  ((struct smb2_change_notify_rsp *)shdr)->OutputBufferLength);
+		break;
 	default:
-		/* BB FIXME for unimplemented cases above */
-		cifs_dbg(VFS, "no length check for command\n");
+		cifs_dbg(VFS, "no length check for command %d\n", le16_to_cpu(shdr->Command));
 		break;
 	}
 

fs/cifs/smb2ops.c

@@ -2148,7 +2148,7 @@ smb3_notify(const unsigned int xid, struct file *pfile,
 
 	tcon = cifs_sb_master_tcon(cifs_sb);
 	oparms.tcon = tcon;
-	oparms.desired_access = FILE_READ_ATTRIBUTES;
+	oparms.desired_access = FILE_READ_ATTRIBUTES | FILE_READ_DATA;
 	oparms.disposition = FILE_OPEN;
 	oparms.create_options = cifs_create_options(cifs_sb, 0);
 	oparms.fid = &fid;