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From:   Ian Abbott <abbotti@mev.co.uk>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Ian Abbott <abbotti@mev.co.uk>,
        H Hartley Sweeten <hsweeten@visionengravers.com>,
        Johan Hovold <johan@kernel.org>, stable@vger.kernel.org
Subject: [PATCH v2] comedi: vmk80xx: fix expression for tx buffer size
Date:   Tue,  7 Jun 2022 18:18:19 +0100
Message-Id: <20220607171819.4121-1-abbotti@mev.co.uk>
In-Reply-To: <d2696256-639b-4b20-3612-6dcfe68313a1@mev.co.uk>
References: <d2696256-639b-4b20-3612-6dcfe68313a1@mev.co.uk>
MIME-Version: 1.0
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Precedence: bulk

The expression for setting the size of the allocated bulk TX buffer
(`devpriv->usb_tx_buf`) is calling `usb_endpoint_maxp(devpriv->ep_rx)`,
which is using the wrong endpoint (should be `devpriv->ep_tx`).  Fix it.

Fixes: a23461c47482 ("comedi: vmk80xx: fix transfer-buffer overflow")
Cc: Johan Hovold <johan@kernel.org>
Cc: stable@vger.kernel.org # 4.9+
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: Johan Hovold <johan@kernel.org>
---
v2: Amended Cc: stable@vger.kernel.org line to apply to 4.9+.
    Added Reviewed-by: Johan Hovold

 drivers/comedi/drivers/vmk80xx.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/comedi/drivers/vmk80xx.c b/drivers/comedi/drivers/vmk80xx.c
index 46023adc5395..4536ed43f65b 100644
--- a/drivers/comedi/drivers/vmk80xx.c
+++ b/drivers/comedi/drivers/vmk80xx.c
@@ -684,7 +684,7 @@ static int vmk80xx_alloc_usb_buffers(struct comedi_device *dev)
 	if (!devpriv->usb_rx_buf)
 		return -ENOMEM;
 
-	size = max(usb_endpoint_maxp(devpriv->ep_rx), MIN_BUF_SIZE);
+	size = max(usb_endpoint_maxp(devpriv->ep_tx), MIN_BUF_SIZE);
 	devpriv->usb_tx_buf = kzalloc(size, GFP_KERNEL);
 	if (!devpriv->usb_tx_buf)
 		return -ENOMEM;
-- 
2.35.1