3.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Florian Westphal <f...@strlen.de>

[ 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 <f...@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pa...@netfilter.org>
Signed-off-by: Sasha Levin <alexander.le...@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 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])


Reply via email to