cifs: Implement is_network_name_deleted for SMB1

This change allows Linux SMB1 client to autoreconnect the share when it is
modified on server by admin operation which removes and re-adds it.

Implementation is reused from SMB2+ is_network_name_deleted callback. There
are just adjusted checks for error codes and access to struct smb_hdr.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

diff --git a/fs/smb/client/smb1ops.c b/fs/smb/client/smb1ops.c
index ad89f60207ab714d2f5bbf0cdeeb96b599e39035..26df807fbe7a9acb651152b38a021ea655e5f68d 100644 (file)
--- a/fs/smb/client/smb1ops.c
+++ b/fs/smb/client/smb1ops.c
@@ -14,6 +14,8 @@
 #include "cifspdu.h"
 #include "cifs_unicode.h"
 #include "fs_context.h"
+#include "nterr.h"
+#include "smberr.h"
 
 /*
  * An NT cancel request header looks just like the original request except:
@@ -1062,6 +1064,47 @@ cifs_make_node(unsigned int xid, struct inode *inode,
                                  full_path, mode, dev);
 }
 
+static bool
+cifs_is_network_name_deleted(char *buf, struct TCP_Server_Info *server)
+{
+       struct smb_hdr *shdr = (struct smb_hdr *)buf;
+       struct TCP_Server_Info *pserver;
+       struct cifs_ses *ses;
+       struct cifs_tcon *tcon;
+
+       if (shdr->Flags2 & SMBFLG2_ERR_STATUS) {
+               if (shdr->Status.CifsError != cpu_to_le32(NT_STATUS_NETWORK_NAME_DELETED))
+                       return false;
+       } else {
+               if (shdr->Status.DosError.ErrorClass != ERRSRV ||
+                   shdr->Status.DosError.Error != cpu_to_le16(ERRinvtid))
+                       return false;
+       }
+
+       /* If server is a channel, select the primary channel */
+       pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
+
+       spin_lock(&cifs_tcp_ses_lock);
+       list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
+               if (cifs_ses_exiting(ses))
+                       continue;
+               list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
+                       if (tcon->tid == shdr->Tid) {
+                               spin_lock(&tcon->tc_lock);
+                               tcon->need_reconnect = true;
+                               spin_unlock(&tcon->tc_lock);
+                               spin_unlock(&cifs_tcp_ses_lock);
+                               pr_warn_once("Server share %s deleted.\n",
+                                            tcon->tree_name);
+                               return true;
+                       }
+               }
+       }
+       spin_unlock(&cifs_tcp_ses_lock);
+
+       return false;
+}
+
 struct smb_version_operations smb1_operations = {
        .send_cancel = send_nt_cancel,
        .compare_fids = cifs_compare_fids,
@@ -1146,6 +1189,7 @@ struct smb_version_operations smb1_operations = {
        .get_acl_by_fid = get_cifs_acl_by_fid,
        .set_acl = set_cifs_acl,
        .make_node = cifs_make_node,
+       .is_network_name_deleted = cifs_is_network_name_deleted,
 };
 
 struct smb_version_values smb1_values = {