64bit accesses unaligned

[Bryan Phillippe]

Sorry about the attachment; trying again...

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Here is the most significant part:

Index: src/lib/route/link.c
===================================================================
--- src/lib/route/link.c.orig
+++ src/lib/route/link.c
@@ -467,38 +467,48 @@ static int link_msg_parser(struct nl_cac
 
                link->ce_mask |= LINK_ATTR_STATS;
        }
 
        if (tb[IFLA_STATS64]) {
-               struct rtnl_link_stats64 *st = nla_data(tb[IFLA_STATS64]);
+               /*
+                * This structure contains 64bit parameters, and per the
+                * documentation in lib/attr.c, must not be accessed
+                * directly (because of alignment to 4 instead of 8).
+                * Therefore, copy the data to the stack and access it from
+                * there, where it will be aligned to 8.
+                */
...

Thanks,
--
-bp


On Aug 11, 2011, at 11:43 AM, Bryan Phillippe wrote:

> Hello,
> 
> I'm using libnl-3.0 on an ARM processor and found a problem with unaligned accesses to 64bit variables.  This patch explains what I found - what are your thoughts?
> 
> <libnl.unaligned.patch>
> 
> Thanks,
> --
> -bp
> 
>