From cf16f408364efd8a68f39011a3b073c83a03612d Mon Sep 17 00:00:00 2001 From: Xinyu Liu Date: Mon, 30 Jun 2025 10:02:56 +0800 Subject: [PATCH] usb: core: config: Prevent OOB read in SS endpoint companion parsing usb_parse_ss_endpoint_companion() checks descriptor type before length, enabling a potentially odd read outside of the buffer size. Fix this up by checking the size first before looking at any of the fields in the descriptor. Signed-off-by: Xinyu Liu Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/config.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c index fc0cfd94cbab..42468bbeffd2 100644 --- a/drivers/usb/core/config.c +++ b/drivers/usb/core/config.c @@ -107,8 +107,14 @@ static void usb_parse_ss_endpoint_companion(struct device *ddev, int cfgno, */ desc = (struct usb_ss_ep_comp_descriptor *) buffer; - if (desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP || - size < USB_DT_SS_EP_COMP_SIZE) { + if (size < USB_DT_SS_EP_COMP_SIZE) { + dev_notice(ddev, + "invalid SuperSpeed endpoint companion descriptor " + "of length %d, skipping\n", size); + return; + } + + if (desc->bDescriptorType != USB_DT_SS_ENDPOINT_COMP) { dev_notice(ddev, "No SuperSpeed endpoint companion for config %d " " interface %d altsetting %d ep %d: " "using minimum values\n", -- 2.51.0