target/linux/generic/patches-3.10/003-11-008-hso-Fix-stack-corruption-on-some-architectures.patch

   1 From e75dc677ff8d06ffa61bef6fee436227ae5440c6 Mon Sep 17 00:00:00 2001
   2 From: Daniel Gimpelevich <daniel@gimpelevich.san-francisco.ca.us>
   3 Date: Wed, 21 Aug 2013 01:43:19 -0700
   4 Subject: [PATCH] hso: Fix stack corruption on some architectures
   5
   6 commit e75dc677ff8d06ffa61bef6fee436227ae5440c6 upstream.
   7
   8 As Sergei Shtylyov explained in the #mipslinux IRC channel:
   9 [Mon 2013-08-19 12:28:21 PM PDT] <headless> guys, are you sure it's not "DMA off stack" case?
  10 [Mon 2013-08-19 12:28:35 PM PDT] <headless> it's a known stack corruptor on non-coherent arches
  11 [Mon 2013-08-19 12:31:48 PM PDT] <DonkeyHotei> headless: for usb/ehci?
  12 [Mon 2013-08-19 12:34:11 PM PDT] <DonkeyHotei> headless: explain
  13 [Mon 2013-08-19 12:35:38 PM PDT] <headless> usb_control_msg() (or other such func) should not use buffer on stack. DMA from/to stack is prohibited
  14 [Mon 2013-08-19 12:35:58 PM PDT] <headless> and EHCI uses DMA on control xfers (as well as all the others)
  15
  16 Signed-off-by: Daniel Gimpelevich <daniel@gimpelevich.san-francisco.ca.us>
  17 Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  18 Signed-off-by: David S. Miller <davem@davemloft.net>
  19 ---
  20  drivers/net/usb/hso.c |    6 +++++-
  21  1 file changed, 5 insertions(+), 1 deletion(-)
  22
  23 --- a/drivers/net/usb/hso.c
  24 +++ b/drivers/net/usb/hso.c
  25 @@ -2816,13 +2816,16 @@ exit:
  26  static int hso_get_config_data(struct usb_interface *interface)
  27  {
  28         struct usb_device *usbdev = interface_to_usbdev(interface);
  29 -       u8 config_data[17];
  30 +       u8 *config_data = kmalloc(17, GFP_KERNEL);
  31         u32 if_num = interface->altsetting->desc.bInterfaceNumber;
  32         s32 result;
  33
  34 +       if (!config_data)
  35 +               return -ENOMEM;
  36         if (usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0),
  37                             0x86, 0xC0, 0, 0, config_data, 17,
  38                             USB_CTRL_SET_TIMEOUT) != 0x11) {
  39 +               kfree(config_data);
  40                 return -EIO;
  41         }
  42
  43 @@ -2873,6 +2876,7 @@ static int hso_get_config_data(struct us
  44         if (config_data[16] & 0x1)
  45                 result |= HSO_INFO_CRC_BUG;
  46
  47 +       kfree(config_data);
  48         return result;
  49  }
  50