diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index b296964b8afa6c4319d07b0593bbcfbbcc97a833..b565d83ba89ed93e78bef0b32eb7aa9c136034ae 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -2031,4 +2031,19 @@ static inline bool is_smb1_server(struct TCP_Server_Info *server) return strcmp(server->vals->version_string, SMB1_VERSION_STRING) == 0; } +static inline bool is_tcon_dfs(struct cifs_tcon *tcon) +{ + /* + * For SMB1, see MS-CIFS 2.4.55 SMB_COM_TREE_CONNECT_ANDX (0x75) and MS-CIFS 3.3.4.4 DFS + * Subsystem Notifies That a Share Is a DFS Share. + * + * For SMB2+, see MS-SMB2 2.2.10 SMB2 TREE_CONNECT Response and MS-SMB2 3.3.4.14 Server + * Application Updates a Share. + */ + if (!tcon || !tcon->ses || !tcon->ses->server) + return false; + return is_smb1_server(tcon->ses->server) ? tcon->Flags & SMB_SHARE_IS_IN_DFS : + tcon->share_flags & (SHI1005_FLAGS_DFS | SHI1005_FLAGS_DFS_ROOT); +} + #endif /* _CIFS_GLOB_H */ diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index a275ee399dcea070fb898c21e5c1e94cda476783..392c44d64d8a69811ed436645941cbcd47e94e0a 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -4909,7 +4909,7 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb_vol *vol) if (!tcon) continue; /* Make sure that requests go through new root servers */ - if (tcon->share_flags & (SHI1005_FLAGS_DFS | SHI1005_FLAGS_DFS_ROOT)) { + if (is_tcon_dfs(tcon)) { put_root_ses(root_ses); set_root_ses(cifs_sb, ses, &root_ses); }