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From: Oliver Neukum <oneukum@suse.com>
To: gregKH@linuxfoundation.org, linux-usb@vger.kernel.org,
	guido.kiener@rohde-schwarz.com, steve_bayless@keysight.com
Cc: Oliver Neukum <oneukum@suse.com>
Subject: [PATCH] usbtmc: more sanity checking for packet size
Date: Tue, 20 Aug 2019 11:28:25 +0200	[thread overview]
Message-ID: <20190820092826.17694-1-oneukum@suse.com> (raw)

A malicious device can make the driver divide ny zero
with a nonsense maximum packet size.

V2: return a sensible error code

SIgned-off-by: Oliver Neukum <oneukum@suse.com>
---
 drivers/usb/class/usbtmc.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c
index 4942122b2346..36858ddd8d9b 100644
--- a/drivers/usb/class/usbtmc.c
+++ b/drivers/usb/class/usbtmc.c
@@ -2362,8 +2362,11 @@ static int usbtmc_probe(struct usb_interface *intf,
 		goto err_put;
 	}
 
+	retcode = -EINVAL;
 	data->bulk_in = bulk_in->bEndpointAddress;
 	data->wMaxPacketSize = usb_endpoint_maxp(bulk_in);
+	if (!data->wMaxPacketSize)
+		goto err_put;
 	dev_dbg(&intf->dev, "Found bulk in endpoint at %u\n", data->bulk_in);
 
 	data->bulk_out = bulk_out->bEndpointAddress;
-- 
2.16.4


                 reply	other threads:[~2019-08-20  9:28 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

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