3.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Florian Westphal <fw@xxxxxxxxx>
[ Upstream commit 932909d9b28d27e807ff8eecb68c7748f6701628 ]
The last rule in the blob has next_entry offset that is same as total size.
This made "ebtables32 -A OUTPUT -d de:ad:be:ef:01:02" fail on 64 bit kernel.
Fixes: b71812168571fa ("netfilter: ebtables: CONFIG_COMPAT: don't trust userland offsets")
Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/bridge/netfilter/ebtables.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -2086,8 +2086,12 @@ static int size_entry_mwt(struct ebt_ent
* offsets are relative to beginning of struct ebt_entry (i.e., 0).
*/
for (i = 0; i < 4 ; ++i) {
- if (offsets[i] >= *total)
+ if (offsets[i] > *total)
return -EINVAL;
+
+ if (i < 3 && offsets[i] == *total)
+ return -EINVAL;
+
if (i == 0)
continue;
if (offsets[i-1] > offsets[i])
