diff options
| author | Kristian Evensen <kristian.evensen@gmail.com> | 2019-05-03 17:40:07 +0200 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2019-05-06 15:15:02 +0200 |
| commit | f8e608982022fad035160870f5b06086d3cba54d (patch) | |
| tree | dcb27b74b7f52d4c9ef13dfe2b571d85e94f66c3 /net | |
| parent | 43c8f131184faf20c07221f3e09724611c6525d8 (diff) | |
netfilter: ctnetlink: Resolve conntrack L3-protocol flush regression
Commit 59c08c69c278 ("netfilter: ctnetlink: Support L3 protocol-filter
on flush") introduced a user-space regression when flushing connection
track entries. Before this commit, the nfgen_family field was not used
by the kernel and all entries were removed. Since this commit,
nfgen_family is used to filter out entries that should not be removed.
One example a broken tool is conntrack. conntrack always sets
nfgen_family to AF_INET, so after 59c08c69c278 only IPv4 entries were
removed with the -F parameter.
Pablo Neira Ayuso suggested using nfgenmsg->version to resolve the
regression, and this commit implements his suggestion. nfgenmsg->version
is so far set to zero, so it is well-suited to be used as a flag for
selecting old or new flush behavior. If version is 0, nfgen_family is
ignored and all entries are used. If user-space sets the version to one
(or any other value than 0), then the new behavior is used. As version
only can have two valid values, I chose not to add a new
NFNETLINK_VERSION-constant.
Fixes: 59c08c69c278 ("netfilter: ctnetlink: Support L3 protocol-filter on flush")
Reported-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Kristian Evensen <kristian.evensen@gmail.com>
Tested-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/netfilter/nf_conntrack_netlink.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index d7f61b0547c6..d2715b4d2e72 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -1254,7 +1254,7 @@ static int ctnetlink_del_conntrack(struct net *net, struct sock *ctnl, struct nf_conntrack_tuple tuple; struct nf_conn *ct; struct nfgenmsg *nfmsg = nlmsg_data(nlh); - u_int8_t u3 = nfmsg->nfgen_family; + u_int8_t u3 = nfmsg->version ? nfmsg->nfgen_family : AF_UNSPEC; struct nf_conntrack_zone zone; int err; |