vhost: fix fd leak in dirty logging setup

[ upstream commit 6dc3f11 ]

This patch fixes a file descriptor leak which happens
in the error path of vhost_user_set_log_base().

Fixes: 4796ad6 ("examples/vhost: import userspace vhost application")

Reported-by: Xuan Ding <xuan.ding@intel.com>
Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Chenbo Xia <chenbo.xia@intel.com>
Reviewed-by: Xueming Li <xuemingl@nvidia.com>

lib/librte_vhost/vhost_user.c

@@ -1608,7 +1608,7 @@ vhost_user_set_log_base(struct virtio_net **pdev, struct VhostUserMsg *msg,
 		RTE_LOG(ERR, VHOST_CONFIG,
 			"invalid log base msg size: %"PRId32" != %d\n",
 			msg->size, (int)sizeof(VhostUserLog));
-		return VH_RESULT_ERR;
+		goto close_msg_fds;
 	}
 
 	size = msg->payload.log.mmap_size;
@@ -1619,7 +1619,7 @@ vhost_user_set_log_base(struct virtio_net **pdev, struct VhostUserMsg *msg,
 		RTE_LOG(ERR, VHOST_CONFIG,
 			"log offset %#"PRIx64" and log size %#"PRIx64" overflow\n",
 			off, size);
-		return VH_RESULT_ERR;
+		goto close_msg_fds;
 	}
 
 	RTE_LOG(INFO, VHOST_CONFIG,
@@ -1656,6 +1656,10 @@ vhost_user_set_log_base(struct virtio_net **pdev, struct VhostUserMsg *msg,
 	msg->fd_num = 0;
 
 	return VH_RESULT_REPLY;
+
+close_msg_fds:
+	close_msg_fds(msg);
+	return VH_RESULT_ERR;
 }
 
 static int vhost_user_set_log_fd(struct virtio_net **pdev __rte_unused,