5.10-stable review patch. If anyone has any objections, please let me know.
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From: Xinyu Liu katieeliu@tencent.com
commit cf16f408364efd8a68f39011a3b073c83a03612d upstream.
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 katieeliu@tencent.com Cc: stable stable@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/core/config.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
--- a/drivers/usb/core/config.c +++ b/drivers/usb/core/config.c @@ -81,8 +81,14 @@ static void usb_parse_ss_endpoint_compan */ 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",