smb: client: Fix refcount leak for cifs_sb_tlink

Fix three refcount inconsistency issues related to `cifs_sb_tlink`.

Comments for `cifs_sb_tlink` state that `cifs_put_tlink()` needs to be
called after successful calls to `cifs_sb_tlink()`. Three calls fail to
update refcount accordingly, leading to possible resource leaks.

Fixes: 8ceb98437946 ("CIFS: Move rename to ops struct")
Fixes: 2f1afe25997f ("cifs: Use smb 2 - 3 and cifsacl mount options getacl functions")
Fixes: 366ed846df60 ("cifs: Use smb 2 - 3 and cifsacl mount options setacl function")
Cc: stable@vger.kernel.org
Signed-off-by: Shuhao Fu <sfual@cse.ust.hk>
Signed-off-by: Steve French <stfrench@microsoft.com>

diff --git a/fs/smb/client/inode.c b/fs/smb/client/inode.c
index 239dd84a336f389237055fba87cfcbbab7dff433..098a79b7a9596c254f547e864acc7be23609293f 100644 (file)
--- a/fs/smb/client/inode.c
+++ b/fs/smb/client/inode.c
@@ -2431,8 +2431,10 @@ cifs_do_rename(const unsigned int xid, struct dentry *from_dentry,
        tcon = tlink_tcon(tlink);
        server = tcon->ses->server;
 
-       if (!server->ops->rename)
-               return -ENOSYS;
+       if (!server->ops->rename) {
+               rc = -ENOSYS;
+               goto do_rename_exit;
+       }
 
        /* try path-based rename first */
        rc = server->ops->rename(xid, tcon, from_dentry,

diff --git a/fs/smb/client/smb2ops.c b/fs/smb/client/smb2ops.c
index 7c392cf5940bb3e63187488d5560c408951bbedd..95cd484cfbba5b9f800f4d46cd1f7ee509ced0a1 100644 (file)
--- a/fs/smb/client/smb2ops.c
+++ b/fs/smb/client/smb2ops.c
@@ -3212,8 +3212,7 @@ get_smb2_acl_by_path(struct cifs_sb_info *cifs_sb,
        utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
        if (!utf16_path) {
                rc = -ENOMEM;
-               free_xid(xid);
-               return ERR_PTR(rc);
+               goto put_tlink;
        }
 
        oparms = (struct cifs_open_parms) {
@@ -3245,6 +3244,7 @@ get_smb2_acl_by_path(struct cifs_sb_info *cifs_sb,
                SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
        }
 
+put_tlink:
        cifs_put_tlink(tlink);
        free_xid(xid);
 
@@ -3285,8 +3285,7 @@ set_smb2_acl(struct smb_ntsd *pnntsd, __u32 acllen,
        utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
        if (!utf16_path) {
                rc = -ENOMEM;
-               free_xid(xid);
-               return rc;
+               goto put_tlink;
        }
 
        oparms = (struct cifs_open_parms) {
@@ -3307,6 +3306,7 @@ set_smb2_acl(struct smb_ntsd *pnntsd, __u32 acllen,
                SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
        }
 
+put_tlink:
        cifs_put_tlink(tlink);
        free_xid(xid);
        return rc;