blob: 1ba20749e27456992dbe93760afad7d09f15a83a [file] [log] [blame]
From dd4c1205435c7564b61e4296c3543fedc06a1d2b Mon Sep 17 00:00:00 2001
From: Qiujun Huang <hqjagain@gmail.com>
Date: Wed, 25 Mar 2020 15:52:37 +0800
Subject: [PATCH] USB: serial: io_edgeport: fix slab-out-of-bounds read in
edge_interrupt_callback
commit 57aa9f294b09463492f604feaa5cc719beaace32 upstream.
Fix slab-out-of-bounds read in the interrupt-URB completion handler.
The boundary condition should be (length - 1) as we access
data[position + 1].
Reported-and-tested-by: syzbot+37ba33391ad5f3935bbd@syzkaller.appspotmail.com
Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/drivers/usb/serial/io_edgeport.c b/drivers/usb/serial/io_edgeport.c
index 5737add6a2a4..4cca0b836f43 100644
--- a/drivers/usb/serial/io_edgeport.c
+++ b/drivers/usb/serial/io_edgeport.c
@@ -710,7 +710,7 @@ static void edge_interrupt_callback(struct urb *urb)
/* grab the txcredits for the ports if available */
position = 2;
portNumber = 0;
- while ((position < length) &&
+ while ((position < length - 1) &&
(portNumber < edge_serial->serial->num_ports)) {
txCredits = data[position] | (data[position+1] << 8);
if (txCredits) {
--
2.7.4