Op vr, 29-02-2008 te 13:48 +0100, schreef Patrick McHardy:
> Pavel Emelyanov wrote:
> > I've sent this patch some days ago to Bart, but with no answer...
Sorry about that.
> >
> > When trying to do
> >
> > # ebtables -A FORWARD --among-src 0:12:34:56:78:9a=192.168.0.10 -j ACCEPT
> >
> > on x86_64 box the ebt_among->check() callback warns me that
> >
> > ebtables: among: wrong size: 1060 against expected 1056, rounded to 1056
> >
> > So the suggested fix is to move the alignment in the kernel. After
> > the fix the rule is added and appears in the ebtables -L output.
>
>
> It seems the kernel is correct and userspace is doing it
> wrong, so I think userspace should be fixed instead.
> The problem with your patch is that is causes misalignment
> for following structures that contain u64 members.
Pavel, please try the attached userspace patch to see if it fixes the
problem (and let me know the result).
cheers,
Bart
--- ebtables-v2.0.8-2/extensions/ebt_among.c.old 2008-03-02 16:08:13.000000000 +0100
+++ ebtables-v2.0.8-2/extensions/ebt_among.c 2008-03-02 16:06:55.000000000 +0100
@@ -68,6 +68,7 @@ static void print_help()
" 00:00:00:fa:eb:fe=153.19.120.250,00:00:00:fa:eb:fe=192.168.0.1\n"
);
}
+static int old_size;
static void init(struct ebt_entry_match *match)
{
@@ -75,6 +76,7 @@ static void init(struct ebt_entry_match
(struct ebt_among_info *) match->data;
memset(amonginfo, 0, sizeof(struct ebt_among_info));
+ old_size = sizeof(struct ebt_among_info);
}
static struct ebt_mac_wormhash *new_wormhash(int n)
@@ -308,7 +310,7 @@ static int parse(int c, char **argv, int
(struct ebt_among_info *) (*match)->data;
struct ebt_mac_wormhash *wh;
struct ebt_entry_match *h;
- int new_size, old_size;
+ int new_size;
long flen;
int fd;
@@ -354,21 +356,23 @@ static int parse(int c, char **argv, int
if (ebt_errormsg[0] != '\0')
break;
- old_size = sizeof(struct ebt_entry_match) + (**match).match_size;
- h = malloc((new_size = old_size + ebt_mac_wormhash_size(wh)));
+ new_size = old_size+ebt_mac_wormhash_size(wh);
+ h = malloc(sizeof(struct ebt_entry_match)+EBT_ALIGN(new_size));
if (!h)
ebt_print_memory();
- memcpy(h, *match, old_size);
- memcpy((char *) h + old_size, wh, ebt_mac_wormhash_size(wh));
- h->match_size = new_size - sizeof(struct ebt_entry_match);
+ memcpy(h, *match, old_size+sizeof(struct ebt_entry_match));
+ memcpy((char *)h+old_size+sizeof(struct ebt_entry_match), wh,
+ ebt_mac_wormhash_size(wh));
+ h->match_size = EBT_ALIGN(new_size);
info = (struct ebt_among_info *) h->data;
if (c == AMONG_DST) {
info->wh_dst_ofs =
- old_size - sizeof(struct ebt_entry_match);
+ old_size;
} else {
info->wh_src_ofs =
- old_size - sizeof(struct ebt_entry_match);
+ old_size;
}
+ old_size = new_size;
free(*match);
*match = h;
free(wh);
