From e75dc677ff8d06ffa61bef6fee436227ae5440c6 Mon Sep 17 00:00:00 2001 From: Daniel Gimpelevich Date: Wed, 21 Aug 2013 01:43:19 -0700 Subject: [PATCH] hso: Fix stack corruption on some architectures commit e75dc677ff8d06ffa61bef6fee436227ae5440c6 upstream. As Sergei Shtylyov explained in the #mipslinux IRC channel: [Mon 2013-08-19 12:28:21 PM PDT] guys, are you sure it's not "DMA off stack" case? [Mon 2013-08-19 12:28:35 PM PDT] it's a known stack corruptor on non-coherent arches [Mon 2013-08-19 12:31:48 PM PDT] headless: for usb/ehci? [Mon 2013-08-19 12:34:11 PM PDT] headless: explain [Mon 2013-08-19 12:35:38 PM PDT] usb_control_msg() (or other such func) should not use buffer on stack. DMA from/to stack is prohibited [Mon 2013-08-19 12:35:58 PM PDT] and EHCI uses DMA on control xfers (as well as all the others) Signed-off-by: Daniel Gimpelevich Acked-by: Greg Kroah-Hartman Signed-off-by: David S. Miller --- drivers/net/usb/hso.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/drivers/net/usb/hso.c +++ b/drivers/net/usb/hso.c @@ -2816,13 +2816,16 @@ exit: static int hso_get_config_data(struct usb_interface *interface) { struct usb_device *usbdev = interface_to_usbdev(interface); - u8 config_data[17]; + u8 *config_data = kmalloc(17, GFP_KERNEL); u32 if_num = interface->altsetting->desc.bInterfaceNumber; s32 result; + if (!config_data) + return -ENOMEM; if (usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0), 0x86, 0xC0, 0, 0, config_data, 17, USB_CTRL_SET_TIMEOUT) != 0x11) { + kfree(config_data); return -EIO; } @@ -2873,6 +2876,7 @@ static int hso_get_config_data(struct us if (config_data[16] & 0x1) result |= HSO_INFO_CRC_BUG; + kfree(config_data); return result; }