ata: libata: Fix memory leak for error path in ata_host_alloc()

In ata_host_alloc(), if devres_alloc() fails to allocate the device host
resource data pointer, the already allocated ata_host structure is not
freed before returning from the function. This results in a potential
memory leak.

Call kfree(host) before jumping to the error handling path to ensure
that the ata_host structure is properly freed if devres_alloc() fails.

Fixes: 2623c7a5 ("libata: add refcounting to ata_host")
Cc: stable@vger.kernel.org
Signed-off-by: Zheng Qixing <zhengqixing@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>

drivers/ata/libata-core.c

@@ -5593,8 +5593,10 @@ struct ata_host *ata_host_alloc(struct device *dev, int n_ports)
 	}
 
 	dr = devres_alloc(ata_devres_release, 0, GFP_KERNEL);
-	if (!dr)
+	if (!dr) {
+		kfree(host);
 		goto err_out;
+	}
 
 	devres_add(dev, dr);
 	dev_set_drvdata(dev, host);