diff --git a/package/libusb/0001-linux_usbfs-Fix-parsing-of-descriptors-for-multi-con.patch b/package/libusb/0001-linux_usbfs-Fix-parsing-of-descriptors-for-multi-con.patch new file mode 100644 index 0000000000..601b322e54 --- /dev/null +++ b/package/libusb/0001-linux_usbfs-Fix-parsing-of-descriptors-for-multi-con.patch @@ -0,0 +1,62 @@ +From 623e2a995d156e115c91f56a3ec691bdc333df8b Mon Sep 17 00:00:00 2001 +From: Chris Dickens +Date: Sun, 13 Dec 2020 15:49:19 -0800 +Subject: [PATCH 1/1] 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 +(cherry picked from commit f6d2cb561402c3b6d3627c0eb89e009b503d9067) +Signed-off-by: John Keeping +--- + libusb/os/linux_usbfs.c | 12 ++++++++---- + 1 file changed, 8 insertions(+), 4 deletions(-) + +diff --git a/libusb/os/linux_usbfs.c b/libusb/os/linux_usbfs.c +index fb2ed53..4d2dc8d 100644 +--- a/libusb/os/linux_usbfs.c ++++ b/libusb/os/linux_usbfs.c +@@ -641,7 +641,12 @@ static int seek_to_next_config(struct libusb_context *ctx, + 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(struct libusb_device *dev) + } + + 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(struct libusb_device *dev) + 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; +-- +2.30.1 +