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

From: Sergei Shtylyov
Date: Wed Sep 11 2013 - 14:44:31 EST


Hello.

On 09/09/2013 03:39 AM, Marc Weber wrote:

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.

Don't attach the patches, send them inline instead. And please mark the mails with patches with [PATCH] in the subject.

Marc Weber

WBR, Sergei

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