[PATCH 3.12 43/88] Revert "netfilter: ensure number of counters is >0 in do_replace()"

From: Jiri Slaby
Date: Thu Jul 14 2016 - 04:32:15 EST

From: Bernhard Thaler <bernhard.thaler@xxxxxxxx>

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


commit d26e2c9ffa385dd1b646f43c1397ba12af9ed431 upstream.

This partially reverts commit 1086bbe97a07 ("netfilter: ensure number of
counters is >0 in do_replace()") in net/bridge/netfilter/ebtables.c.

Setting rules with ebtables does not work any more with 1086bbe97a07 place.

There is an error message and no rules set in the end.


~# ebtables -t nat -A POSTROUTING --src 12:34:56:78:9a:bc -j DROP
Unable to update the kernel. Two possible causes:
1. Multiple ebtables programs were executing simultaneously. The ebtables
userspace tool doesn't by default support multiple ebtables programs

Reverting the ebtables part of 1086bbe97a07 makes this work again.

Signed-off-by: Bernhard Thaler <bernhard.thaler@xxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
net/bridge/netfilter/ebtables.c | 4 ----
1 file changed, 4 deletions(-)

diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index fbfa24b19127..b166fc2ec4b9 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -1105,8 +1105,6 @@ static int do_replace(struct net *net, const void __user *user,
return -ENOMEM;
if (tmp.num_counters >= INT_MAX / sizeof(struct ebt_counter))
return -ENOMEM;
- if (tmp.num_counters == 0)
- return -EINVAL;

tmp.name[sizeof(tmp.name) - 1] = 0;

@@ -2152,8 +2150,6 @@ static int compat_copy_ebt_replace_from_user(struct ebt_replace *repl,
return -ENOMEM;
if (tmp.num_counters >= INT_MAX / sizeof(struct ebt_counter))
return -ENOMEM;
- if (tmp.num_counters == 0)
- return -EINVAL;

memcpy(repl, &tmp, offsetof(struct ebt_replace, hook_entry));