smb3: add additional null check in SMB2_tcon

Although unlikely to be possible for rsp to be null here,
the check is safer to add, and quiets a Coverity warning.

Addresses-Coverity: 1420428 ("Explicit null dereferenced")
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 48679e0..243de87 100644 (file)
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -1840,7 +1840,7 @@ SMB2_tcon(const unsigned int xid, struct cifs_ses *ses, const char *tree,
        cifs_small_buf_release(req);
        rsp = (struct smb2_tree_connect_rsp *)rsp_iov.iov_base;
        trace_smb3_tcon(xid, tcon->tid, ses->Suid, tree, rc);
-       if (rc != 0) {
+       if ((rc != 0) || (rsp == NULL)) {
                cifs_stats_fail_inc(tcon, SMB2_TREE_CONNECT_HE);
                tcon->need_reconnect = true;
                goto tcon_error_exit;