These changes look good to me.
However, I see other places in the code where these flags are checked
separately. Don't we want to replace all those with is_tcon_dfs()
calls?
Regards,
Shyam
On Thu, Aug 27, 2020 at 8:05 PM Paulo Alcantara <pc@xxxxxx> wrote:
>
> For SMB1, the DFS flag should be checked against tcon->Flags rather
> than tcon->share_flags. While at it, add an is_tcon_dfs() helper to
> check for DFS capability in a more generic way.
>
> Signed-off-by: Paulo Alcantara (SUSE) <pc@xxxxxx>
> ---
> fs/cifs/cifsglob.h | 15 +++++++++++++++
> fs/cifs/connect.c | 2 +-
> 2 files changed, 16 insertions(+), 1 deletion(-)
>
> diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
> index b296964b8afa..b565d83ba89e 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 a275ee399dce..392c44d64d8a 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);
> }
> --
> 2.28.0
>
--
-Shyam
