From: Antonio Ospite <ao2@ao2.it>
Date: Mon, 20 Apr 2015 15:09:19 +0000 (+0200)
Subject: am7xxx: check the return value of libusb_get_configuration()
X-Git-Tag: v0.1.6~27
X-Git-Url: https://git.ao2.it/libam7xxx.git/commitdiff_plain/2bb4878fcc5ccc152634087f0aa13ab1eec56de0?ds=inline;hp=361d1aa96547f527f1c60a871db35c943bc07471

am7xxx: check the return value of libusb_get_configuration()

libusb_get_configuration() can still fail after the device has been
opened, so check its actual return value before trusting the returned
current_configuration.
---

diff --git a/src/am7xxx.c b/src/am7xxx.c
index 1c3f704..b00a6be 100644
--- a/src/am7xxx.c
+++ b/src/am7xxx.c
@@ -734,7 +734,14 @@ static int open_device(am7xxx_context *ctx,
 	 */
 
 	current_configuration = -1;
-	libusb_get_configuration((*dev)->usb_device, &current_configuration);
+	ret = libusb_get_configuration((*dev)->usb_device,
+				       &current_configuration);
+	if (ret < 0) {
+		debug(ctx, "libusb_get_configuration failed: %s\n",
+		      libusb_error_name(ret));
+		goto out_libusb_close;
+	}
+
 	if (current_configuration != (*dev)->desc->configuration) {
 		/*
 		 * In principle kernel drivers bound to each interface should
@@ -772,7 +779,14 @@ static int open_device(am7xxx_context *ctx,
 	 * http://libusb.sourceforge.net/api-1.0/caveats.html
 	 */
 	current_configuration = -1;
-	libusb_get_configuration((*dev)->usb_device, &current_configuration);
+	ret = libusb_get_configuration((*dev)->usb_device,
+				       &current_configuration);
+	if (ret < 0) {
+		debug(ctx, "libusb_get_configuration after claim failed: %s\n",
+		      libusb_error_name(ret));
+		goto out_libusb_close;
+	}
+
 	if (current_configuration != (*dev)->desc->configuration) {
 		debug(ctx, "libusb configuration changed (expected: %hhu, current: %hhu\n",
 		      (*dev)->desc->configuration, current_configuration);