libusb: Fix parsing of descriptors for multi-configuration devices

Prerequisite patch:
Correct a typo in the Changelog and clean up a stray file

Fix changes in libusb which introduced a regression:
Commit e2be556bd2 ("linux_usbfs: Parse config descriptors during device
initialization") introduced a regression for devices with multiple
configurations. The logic that verifies the reported length of the
configuration descriptors failed to count the length of the
configuration descriptor itself and would truncate the actual length by
9 bytes, leading to a parsing error for subsequent descriptors.

Signed-off-by: Georgi Valkov <gvalkov@abv.bg>

1 files changed, 61 insertions, 0 deletions

diff --git a/package/libs/libusb/patches/002-linux_usbfs-Fix-parsing-of-descriptors-for-multi-con.patch b/package/libs/libusb/patches/002-linux_usbfs-Fix-parsing-of-descriptors-for-multi-con.patch
new file mode 100644
index 0000000000..a53a8900de
--- /dev/null
+++ b/package/libs/libusb/patches/002-linux_usbfs-Fix-parsing-of-descriptors-for-multi-con.patch
@@ -0,0 +1,61 @@
+From f6d2cb561402c3b6d3627c0eb89e009b503d9067 Mon Sep 17 00:00:00 2001
+From: Chris Dickens <christopher.a.dickens@gmail.com>
+Date: Sun, 13 Dec 2020 15:49:19 -0800
+Subject: [PATCH] linux_usbfs: Fix parsing of descriptors for
+ multi-configuration devices
+
+Commit e2be556bd2 ("linux_usbfs: Parse config descriptors during device
+initialization") introduced a regression for devices with multiple
+configurations. The logic that verifies the reported length of the
+configuration descriptors failed to count the length of the
+configuration descriptor itself and would truncate the actual length by
+9 bytes, leading to a parsing error for subsequent descriptors.
+
+Closes #825
+
+Signed-off-by: Chris Dickens <christopher.a.dickens@gmail.com>
+---
+ libusb/os/linux_usbfs.c | 12 ++++++++----
+ libusb/version_nano.h   |  2 +-
+ 2 files changed, 9 insertions(+), 5 deletions(-)
+
+--- a/libusb/os/linux_usbfs.c
++++ b/libusb/os/linux_usbfs.c
+@@ -641,7 +641,12 @@ static int seek_to_next_config(struct li
+ 	uint8_t *buffer, size_t len)
+ {
+ 	struct usbi_descriptor_header *header;
+-	int offset = 0;
++	int offset;
++
++	/* Start seeking past the config descriptor */
++	offset = LIBUSB_DT_CONFIG_SIZE;
++	buffer += LIBUSB_DT_CONFIG_SIZE;
++	len -= LIBUSB_DT_CONFIG_SIZE;
+ 
+ 	while (len > 0) {
+ 		if (len < 2) {
+@@ -718,7 +723,7 @@ static int parse_config_descriptors(stru
+ 		}
+ 
+ 		if (priv->sysfs_dir) {
+-			 /*
++			/*
+ 			 * In sysfs wTotalLength is ignored, instead the kernel returns a
+ 			 * config descriptor with verified bLength fields, with descriptors
+ 			 * with an invalid bLength removed.
+@@ -727,8 +732,7 @@ static int parse_config_descriptors(stru
+ 			int offset;
+ 
+ 			if (num_configs > 1 && idx < num_configs - 1) {
+-				offset = seek_to_next_config(ctx, buffer + LIBUSB_DT_CONFIG_SIZE,
+-							     remaining - LIBUSB_DT_CONFIG_SIZE);
++				offset = seek_to_next_config(ctx, buffer, remaining);
+ 				if (offset < 0)
+ 					return offset;
+ 				sysfs_config_len = (uint16_t)offset;
+--- a/libusb/version_nano.h
++++ b/libusb/version_nano.h
+@@ -1 +1 @@
+-#define LIBUSB_NANO 11585
++#define LIBUSB_NANO 11586