From 567e2e9660c71372e8bd50efa9d37a0281e4abe1 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Fri, 13 Dec 2013 08:06:07 -0300 Subject: [PATCH] [media] si470x: don't use buffer on the stack for USB transfers You shouldn't use buffers allocated on the stack for USB transfers, always kmalloc them. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/radio/si470x/radio-si470x-usb.c | 57 +++++++++++++++------------ drivers/media/radio/si470x/radio-si470x.h | 1 + 2 files changed, 32 insertions(+), 26 deletions(-) diff --git a/drivers/media/radio/si470x/radio-si470x-usb.c b/drivers/media/radio/si470x/radio-si470x-usb.c index d6d4d60..cd74025 100644 --- a/drivers/media/radio/si470x/radio-si470x-usb.c +++ b/drivers/media/radio/si470x/radio-si470x-usb.c @@ -137,6 +137,8 @@ MODULE_PARM_DESC(max_rds_errors, "RDS maximum block errors: *1*"); /* interrupt out endpoint 2 every 1 millisecond */ #define UNUSED_REPORT 23 +#define MAX_REPORT_SIZE 64 + /************************************************************************** @@ -208,7 +210,7 @@ MODULE_PARM_DESC(max_rds_errors, "RDS maximum block errors: *1*"); */ static int si470x_get_report(struct si470x_device *radio, void *buf, int size) { - unsigned char *report = (unsigned char *) buf; + unsigned char *report = buf; int retval; retval = usb_control_msg(radio->usbdev, @@ -231,7 +233,7 @@ static int si470x_get_report(struct si470x_device *radio, void *buf, int size) */ static int si470x_set_report(struct si470x_device *radio, void *buf, int size) { - unsigned char *report = (unsigned char *) buf; + unsigned char *report = buf; int retval; retval = usb_control_msg(radio->usbdev, @@ -254,15 +256,14 @@ static int si470x_set_report(struct si470x_device *radio, void *buf, int size) */ int si470x_get_register(struct si470x_device *radio, int regnr) { - unsigned char buf[REGISTER_REPORT_SIZE]; int retval; - buf[0] = REGISTER_REPORT(regnr); + radio->usb_buf[0] = REGISTER_REPORT(regnr); - retval = si470x_get_report(radio, (void *) &buf, sizeof(buf)); + retval = si470x_get_report(radio, radio->usb_buf, REGISTER_REPORT_SIZE); if (retval >= 0) - radio->registers[regnr] = get_unaligned_be16(&buf[1]); + radio->registers[regnr] = get_unaligned_be16(&radio->usb_buf[1]); return (retval < 0) ? -EINVAL : 0; } @@ -273,13 +274,12 @@ int si470x_get_register(struct si470x_device *radio, int regnr) */ int si470x_set_register(struct si470x_device *radio, int regnr) { - unsigned char buf[REGISTER_REPORT_SIZE]; int retval; - buf[0] = REGISTER_REPORT(regnr); - put_unaligned_be16(radio->registers[regnr], &buf[1]); + radio->usb_buf[0] = REGISTER_REPORT(regnr); + put_unaligned_be16(radio->registers[regnr], &radio->usb_buf[1]); - retval = si470x_set_report(radio, (void *) &buf, sizeof(buf)); + retval = si470x_set_report(radio, radio->usb_buf, REGISTER_REPORT_SIZE); return (retval < 0) ? -EINVAL : 0; } @@ -295,18 +295,17 @@ int si470x_set_register(struct si470x_device *radio, int regnr) */ static int si470x_get_all_registers(struct si470x_device *radio) { - unsigned char buf[ENTIRE_REPORT_SIZE]; int retval; unsigned char regnr; - buf[0] = ENTIRE_REPORT; + radio->usb_buf[0] = ENTIRE_REPORT; - retval = si470x_get_report(radio, (void *) &buf, sizeof(buf)); + retval = si470x_get_report(radio, radio->usb_buf, ENTIRE_REPORT_SIZE); if (retval >= 0) for (regnr = 0; regnr < RADIO_REGISTER_NUM; regnr++) radio->registers[regnr] = get_unaligned_be16( - &buf[regnr * RADIO_REGISTER_SIZE + 1]); + &radio->usb_buf[regnr * RADIO_REGISTER_SIZE + 1]); return (retval < 0) ? -EINVAL : 0; } @@ -323,14 +322,13 @@ static int si470x_get_all_registers(struct si470x_device *radio) static int si470x_set_led_state(struct si470x_device *radio, unsigned char led_state) { - unsigned char buf[LED_REPORT_SIZE]; int retval; - buf[0] = LED_REPORT; - buf[1] = LED_COMMAND; - buf[2] = led_state; + radio->usb_buf[0] = LED_REPORT; + radio->usb_buf[1] = LED_COMMAND; + radio->usb_buf[2] = led_state; - retval = si470x_set_report(radio, (void *) &buf, sizeof(buf)); + retval = si470x_set_report(radio, radio->usb_buf, LED_REPORT_SIZE); return (retval < 0) ? -EINVAL : 0; } @@ -346,19 +344,18 @@ static int si470x_set_led_state(struct si470x_device *radio, */ static int si470x_get_scratch_page_versions(struct si470x_device *radio) { - unsigned char buf[SCRATCH_REPORT_SIZE]; int retval; - buf[0] = SCRATCH_REPORT; + radio->usb_buf[0] = SCRATCH_REPORT; - retval = si470x_get_report(radio, (void *) &buf, sizeof(buf)); + retval = si470x_get_report(radio, radio->usb_buf, SCRATCH_REPORT_SIZE); if (retval < 0) dev_warn(&radio->intf->dev, "si470x_get_scratch: " "si470x_get_report returned %d\n", retval); else { - radio->software_version = buf[1]; - radio->hardware_version = buf[2]; + radio->software_version = radio->usb_buf[1]; + radio->hardware_version = radio->usb_buf[2]; } return (retval < 0) ? -EINVAL : 0; @@ -509,6 +506,7 @@ static void si470x_usb_release(struct v4l2_device *v4l2_dev) v4l2_device_unregister(&radio->v4l2_dev); kfree(radio->int_in_buffer); kfree(radio->buffer); + kfree(radio->usb_buf); kfree(radio); } @@ -593,6 +591,11 @@ static int si470x_usb_driver_probe(struct usb_interface *intf, retval = -ENOMEM; goto err_initial; } + radio->usb_buf = kmalloc(MAX_REPORT_SIZE, GFP_KERNEL); + if (radio->usb_buf == NULL) { + retval = -ENOMEM; + goto err_radio; + } radio->usbdev = interface_to_usbdev(intf); radio->intf = intf; radio->band = 1; /* Default to 76 - 108 MHz */ @@ -612,7 +615,7 @@ static int si470x_usb_driver_probe(struct usb_interface *intf, if (!radio->int_in_endpoint) { dev_info(&intf->dev, "could not find interrupt in endpoint\n"); retval = -EIO; - goto err_radio; + goto err_usbbuf; } int_end_size = le16_to_cpu(radio->int_in_endpoint->wMaxPacketSize); @@ -621,7 +624,7 @@ static int si470x_usb_driver_probe(struct usb_interface *intf, if (!radio->int_in_buffer) { dev_info(&intf->dev, "could not allocate int_in_buffer"); retval = -ENOMEM; - goto err_radio; + goto err_usbbuf; } radio->int_in_urb = usb_alloc_urb(0, GFP_KERNEL); @@ -743,6 +746,8 @@ err_urb: usb_free_urb(radio->int_in_urb); err_intbuffer: kfree(radio->int_in_buffer); +err_usbbuf: + kfree(radio->usb_buf); err_radio: kfree(radio); err_initial: diff --git a/drivers/media/radio/si470x/radio-si470x.h b/drivers/media/radio/si470x/radio-si470x.h index 467e955..4b76604 100644 --- a/drivers/media/radio/si470x/radio-si470x.h +++ b/drivers/media/radio/si470x/radio-si470x.h @@ -167,6 +167,7 @@ struct si470x_device { /* reference to USB and video device */ struct usb_device *usbdev; struct usb_interface *intf; + char *usb_buf; /* Interrupt endpoint handling */ char *int_in_buffer; -- 2.7.4