drivers/net/ethernet/nvidia/forcedeth.c saved_config_space[size] access patch

[Marc Weber]

  1) VER3 and _MAX are of same size:
  #define NV_PCI_REGSZ_VER3       0x604
  #define NV_PCI_REGSZ_MAX        0x604


  2) It looks like there is a case where VER3 get's assigned to
      register_size:

  if (id->driver_data &
  (DEV_HAS_VLAN|DEV_HAS_MSI_X|DEV_HAS_POWER_CNTRL|DEV_HAS_STATISTICS_V2|DEV_HAS_STATISTICS_V
                  np->register_size = NV_PCI_REGSZ_VER3;

  3) the definition of saved_config_space is MAX divided by 4 (size of u32)
  struct fe_priv {
    [...]
    u32 saved_config_space[NV_PCI_REGSZ_MAX/4]

  4) This doesn't stop loop at [size-1]:
    Thus there is the risk that it overrides the field after
    saved_config_space. If that's desired behaviour at least a comment
    is missing IMHO:

  for (i = 0; i <= np->register_size/sizeof(u32); i++)
     np->saved_config_space[i] = readl(base + i*sizeof(u32));

  Such for loop is used twice in forcedeth.c

Patch againstn 4de9ad9bc08 (Fri Sep 6 11:14:33) attached fixing both
using < instead of <=.

If you think I've hit a small bug just fix and commit.
I don't care much about my ownership of this patch.

I didn't test this patch because I don't have the hardware and I think
its a trivial case.

Marc Weber

Attachment: 0001-forcedepth-fix-possible-out-of-bounds-access.patch
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