s3:smbd: let fsp_smb_fname_link() set both sides of the link

We also need to be sure both sides were not linked before.

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>

diff --git a/source3/smbd/files.c b/source3/smbd/files.c
index bcd4a55036b9ad6dd829d21846be49ec44296347..2076d13a4dfc023131753a55d4887e7523bcdfbe 100644 (file)
--- a/source3/smbd/files.c
+++ b/source3/smbd/files.c
@@ -299,6 +299,9 @@ static NTSTATUS fsp_smb_fname_link(struct files_struct *fsp,
 {
        struct fsp_smb_fname_link *link = NULL;
 
+       SMB_ASSERT(*smb_fname_link == NULL);
+       SMB_ASSERT(*smb_fname_fsp == NULL);
+
        link = talloc_zero(fsp, struct fsp_smb_fname_link);
        if (link == NULL) {
                return NT_STATUS_NO_MEMORY;
@@ -307,6 +310,7 @@ static NTSTATUS fsp_smb_fname_link(struct files_struct *fsp,
        link->smb_fname_link = smb_fname_link;
        link->smb_fname_fsp = smb_fname_fsp;
        *smb_fname_link = link;
+       *smb_fname_fsp = fsp;
 
        talloc_set_destructor(link, fsp_smb_fname_link_destructor);
        return NT_STATUS_OK;
@@ -525,9 +529,6 @@ NTSTATUS openat_pathref_fsp(const struct files_struct *dirfsp,
 
        fsp->file_id = vfs_file_id_from_sbuf(conn, &fsp->fsp_name->st);
 
-       fsp->fsp_name->fsp = fsp;
-       smb_fname->fsp = fsp;
-
        status = fsp_smb_fname_link(fsp,
                                    &smb_fname->fsp_link,
                                    &smb_fname->fsp);
@@ -581,13 +582,17 @@ NTSTATUS move_smb_fname_fsp_link(struct smb_filename *smb_fname_dst,
 {
        NTSTATUS status;
 
+       /*
+        * The target should always not be linked yet!
+        */
+       SMB_ASSERT(smb_fname_dst->fsp == NULL);
+       SMB_ASSERT(smb_fname_dst->fsp_link == NULL);
+
        if (smb_fname_src->fsp == NULL) {
                return NT_STATUS_OK;
        }
 
-       smb_fname_dst->fsp = smb_fname_src->fsp;
-
-       status = fsp_smb_fname_link(smb_fname_dst->fsp,
+       status = fsp_smb_fname_link(smb_fname_src->fsp,
                                    &smb_fname_dst->fsp_link,
                                    &smb_fname_dst->fsp);
        if (!NT_STATUS_IS_OK(status)) {