smb: client: fix refcount leak in smb2_set_path_attr

[ Upstream commit b540de9e3b4fab3b9e10f30714a6f5c1b2a50ec3 ]

Fix refcount leak in `smb2_set_path_attr` when path conversion fails.

Function `cifs_get_writable_path` returns `cfile` with its reference
counter `cfile->count` increased on success. Function `smb2_compound_op`
would decrease the reference counter for `cfile`, as stated in its
comment. By calling `smb2_rename_path`, the reference counter of `cfile`
would leak if `cifs_convert_path_to_utf16` fails in `smb2_set_path_attr`.

Fixes: 8de9e86c67ba ("cifs: create a helper to find a writeable handle by path name")
Acked-by: Henrique Carvalho <henrique.carvalho@suse.com>
Signed-off-by: Shuhao Fu <sfual@cse.ust.hk>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/smb/client/smb2inode.c b/fs/smb/client/smb2inode.c
index e441fa2e768979feae86b308fbda49f10ca64a97..ff9cb25327458a0a0176fdebf95471dec8da34b9 100644 (file)
--- a/fs/smb/client/smb2inode.c
+++ b/fs/smb/client/smb2inode.c
@@ -1294,6 +1294,8 @@ static int smb2_set_path_attr(const unsigned int xid, struct cifs_tcon *tcon,
        smb2_to_name = cifs_convert_path_to_utf16(to_name, cifs_sb);
        if (smb2_to_name == NULL) {
                rc = -ENOMEM;
+               if (cfile)
+                       cifsFileInfo_put(cfile);
                goto smb2_rename_path;
        }
        in_iov.iov_base = smb2_to_name;