From c380600bf71c35dc23aa0c3628a1013ec10cb349 Mon Sep 17 00:00:00 2001
From: Mathias Payer <mathias.payer@nebelwelt.net>
Date: Wed, 5 Dec 2018 21:19:59 +0100
Subject: USB: check usb_get_extra_descriptor for proper size

commit 704620afc70cf47abb9d6a1a57f3825d2bca49cf upstream.

When reading an extra descriptor, we need to properly check the minimum
and maximum size allowed, to prevent from invalid data being sent by a
device.

Reported-by: Hui Peng <benquike@gmail.com>
Reported-by: Mathias Payer <mathias.payer@nebelwelt.net>
Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Hui Peng <benquike@gmail.com>
Signed-off-by: Mathias Payer <mathias.payer@nebelwelt.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 include/linux/usb.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'include')

diff --git a/include/linux/usb.h b/include/linux/usb.h
index 092b5658b9c3..5c03ebc6dfa0 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -334,11 +334,11 @@ struct usb_host_bos {
 };
 
 int __usb_get_extra_descriptor(char *buffer, unsigned size,
-	unsigned char type, void **ptr);
+	unsigned char type, void **ptr, size_t min);
 #define usb_get_extra_descriptor(ifpoint, type, ptr) \
 				__usb_get_extra_descriptor((ifpoint)->extra, \
 				(ifpoint)->extralen, \
-				type, (void **)ptr)
+				type, (void **)ptr, sizeof(**(ptr)))
 
 /* ----------------------------------------------------------------------- */
 
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