vfio-ccw: Fix memory leak and don't call cp_free in cp_init

We don't set cp->initialized to true so calling cp_free
will just return and not do anything.

Also fix a memory leak where we fail to free a ccwchain
on an error.

Fixes: 812271b9 ("s390/cio: Squash cp_free() and cp_unpin_free()")
Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
Message-Id: <3173c4216f4555d9765eb6e4922534982bc820e4.1562854091.git.alifm@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>

drivers/s390/cio/vfio_ccw_cp.c

@@ -421,7 +421,7 @@ static int ccwchain_loop_tic(struct ccwchain *chain,
 static int ccwchain_handle_ccw(u32 cda, struct channel_program *cp)
 {
 	struct ccwchain *chain;
-	int len;
+	int len, ret;
 
 	/* Copy 2K (the most we support today) of possible CCWs */
 	len = copy_from_iova(cp->mdev, cp->guest_cp, cda,
@@ -448,7 +448,12 @@ static int ccwchain_handle_ccw(u32 cda, struct channel_program *cp)
 	memcpy(chain->ch_ccw, cp->guest_cp, len * sizeof(struct ccw1));
 
 	/* Loop for tics on this new chain. */
-	return ccwchain_loop_tic(chain, cp);
+	ret = ccwchain_loop_tic(chain, cp);
+
+	if (ret)
+		ccwchain_free(chain);
+
+	return ret;
 }
 
 /* Loop for TICs. */
@@ -642,8 +647,6 @@ int cp_init(struct channel_program *cp, struct device *mdev, union orb *orb)
 
 	/* Build a ccwchain for the first CCW segment */
 	ret = ccwchain_handle_ccw(orb->cmd.cpa, cp);
-	if (ret)
-		cp_free(cp);
 
 	if (!ret) {
 		cp->initialized = true;