From 0448067150dc1e4034b018da253b0ed1c57d16c9 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Tue, 13 Aug 2013 13:27:38 +0200 Subject: [PATCH] USB: quatech2: fix serial DMA-buffer allocations Make sure serial DMA-buffers are allocated separately from containing structure to prevent potential memory corruption on non-cache-coherent systems. Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/quatech2.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/usb/serial/quatech2.c b/drivers/usb/serial/quatech2.c index d997432..79c9b2b 100644 --- a/drivers/usb/serial/quatech2.c +++ b/drivers/usb/serial/quatech2.c @@ -62,6 +62,7 @@ #define MAX_BAUD_RATE 921600 #define DEFAULT_BAUD_RATE 9600 +#define QT2_READ_BUFFER_SIZE 512 /* size of read buffer */ #define QT2_WRITE_BUFFER_SIZE 512 /* size of write buffer */ #define QT2_WRITE_CONTROL_SIZE 5 /* control bytes used for a write */ @@ -112,7 +113,7 @@ struct qt2_serial_private { unsigned char current_port; /* current port for incoming data */ struct urb *read_urb; /* shared among all ports */ - char read_buffer[512]; + char *read_buffer; }; struct qt2_port_private { @@ -142,6 +143,7 @@ static void qt2_release(struct usb_serial *serial) serial_priv = usb_get_serial_data(serial); usb_free_urb(serial_priv->read_urb); + kfree(serial_priv->read_buffer); kfree(serial_priv); } @@ -683,7 +685,7 @@ static int qt2_setup_urbs(struct usb_serial *serial) usb_rcvbulkpipe(serial->dev, port0->bulk_in_endpointAddress), serial_priv->read_buffer, - sizeof(serial_priv->read_buffer), + QT2_READ_BUFFER_SIZE, qt2_read_bulk_callback, serial); status = usb_submit_urb(serial_priv->read_urb, GFP_KERNEL); @@ -718,6 +720,12 @@ static int qt2_attach(struct usb_serial *serial) return -ENOMEM; } + serial_priv->read_buffer = kmalloc(QT2_READ_BUFFER_SIZE, GFP_KERNEL); + if (!serial_priv->read_buffer) { + status = -ENOMEM; + goto err_buf; + } + usb_set_serial_data(serial, serial_priv); status = qt2_setup_urbs(serial); @@ -727,6 +735,8 @@ static int qt2_attach(struct usb_serial *serial) return 0; attach_failed: + kfree(serial_priv->read_buffer); +err_buf: kfree(serial_priv); return status; } -- 2.7.4