diff options
| author | Phil Sutter <phil@nwl.cc> | 2016-04-12 01:31:14 +0200 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2016-04-13 01:16:57 +0200 |
| commit | bcf4934288402be3464110109a4dae3bd6fb3e93 (patch) | |
| tree | bc56faa21bf6d61dd7b94f302c828ef0a50185c9 /net | |
| parent | 644c7e48cb59cfc6988ddc7bf3d3b1ba5fe7fa9d (diff) | |
| download | lwn-bcf4934288402be3464110109a4dae3bd6fb3e93.tar.gz lwn-bcf4934288402be3464110109a4dae3bd6fb3e93.zip | |
netfilter: ebtables: Fix extension lookup with identical name
If a requested extension exists as module and is not loaded,
ebt_check_match() might accidentally use an NFPROTO_UNSPEC one with same
name and fail.
Reproduced with limit match: Given xt_limit and ebt_limit both built as
module, the following would fail:
modprobe xt_limit
ebtables -I INPUT --limit 1/s -j ACCEPT
The fix is to make ebt_check_match() distrust a found NFPROTO_UNSPEC
extension and retry after requesting an appropriate module.
Cc: Florian Westphal <fw@strlen.de>
Signed-off-by: Phil Sutter <phil@nwl.cc>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/bridge/netfilter/ebtables.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c index 8570bc7744c2..5a61f35412a0 100644 --- a/net/bridge/netfilter/ebtables.c +++ b/net/bridge/netfilter/ebtables.c @@ -370,7 +370,11 @@ ebt_check_match(struct ebt_entry_match *m, struct xt_mtchk_param *par, left - sizeof(struct ebt_entry_match) < m->match_size) return -EINVAL; - match = xt_request_find_match(NFPROTO_BRIDGE, m->u.name, 0); + match = xt_find_match(NFPROTO_BRIDGE, m->u.name, 0); + if (IS_ERR(match) || match->family != NFPROTO_BRIDGE) { + request_module("ebt_%s", m->u.name); + match = xt_find_match(NFPROTO_BRIDGE, m->u.name, 0); + } if (IS_ERR(match)) return PTR_ERR(match); m->u.match = match; |