CIFS: Fix NULL pointer deref on SMB2_tcon() failure

If SendReceive2() fails rsp is set to NULL but is dereferenced in the
error handling code.

Cc: stable@vger.kernel.org
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index fa17caa56128..3efcd96b52c5 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -1255,7 +1255,7 @@ SMB2_tcon(const unsigned int xid, struct cifs_ses *ses, const char *tree,
         struct smb2_tree_connect_req *req;
         struct smb2_tree_connect_rsp *rsp = NULL;
         struct kvec iov[2];
-        struct kvec rsp_iov;
+        struct kvec rsp_iov = { NULL, 0 };
         int rc = 0;
         int resp_buftype;
         int unc_path_len;
@@ -1372,7 +1372,7 @@ tcon_exit:
         return rc;
 
 tcon_error_exit:
-        if (rsp->hdr.sync_hdr.Status == STATUS_BAD_NETWORK_NAME) {
+        if (rsp && rsp->hdr.sync_hdr.Status == STATUS_BAD_NETWORK_NAME) {
                 cifs_dbg(VFS, "BAD_NETWORK_NAME: %s\n", tree);
         }
         goto tcon_exit;