From 3e673b23b541b8e7f773b2d378d6eb99831741cd Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Tue, 31 Jul 2018 13:41:23 +0200 Subject: [PATCH] netfilter: fix memory leaks on netlink_dump_start error Shaochun Chen points out we leak dumper filter state allocations stored in dump_control->data in case there is an error before netlink sets cb_running (after which ->done will be called at some point). In order to fix this, add .start functions and move allocations there. Same pattern as used in commit 90fd131afc565159c9e0ea742f082b337e10f8c6 ("netfilter: nf_tables: move dumper state allocation into ->start"). Reported-by: shaochun chen Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_netlink.c | 26 +++++++++++++++++--------- net/netfilter/nfnetlink_acct.c | 29 +++++++++++++---------------- 2 files changed, 30 insertions(+), 25 deletions(-) diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index f981bfa..036207e 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -846,6 +846,21 @@ ctnetlink_alloc_filter(const struct nlattr * const cda[]) #endif } +static int ctnetlink_start(struct netlink_callback *cb) +{ + const struct nlattr * const *cda = cb->data; + struct ctnetlink_filter *filter = NULL; + + if (cda[CTA_MARK] && cda[CTA_MARK_MASK]) { + filter = ctnetlink_alloc_filter(cda); + if (IS_ERR(filter)) + return PTR_ERR(filter); + } + + cb->data = filter; + return 0; +} + static int ctnetlink_filter_match(struct nf_conn *ct, void *data) { struct ctnetlink_filter *filter = data; @@ -1290,19 +1305,12 @@ static int ctnetlink_get_conntrack(struct net *net, struct sock *ctnl, if (nlh->nlmsg_flags & NLM_F_DUMP) { struct netlink_dump_control c = { + .start = ctnetlink_start, .dump = ctnetlink_dump_table, .done = ctnetlink_done, + .data = (void *)cda, }; - if (cda[CTA_MARK] && cda[CTA_MARK_MASK]) { - struct ctnetlink_filter *filter; - - filter = ctnetlink_alloc_filter(cda); - if (IS_ERR(filter)) - return PTR_ERR(filter); - - c.data = filter; - } return netlink_dump_start(ctnl, skb, nlh, &c); } diff --git a/net/netfilter/nfnetlink_acct.c b/net/netfilter/nfnetlink_acct.c index a0e5adf..8fa8bf7 100644 --- a/net/netfilter/nfnetlink_acct.c +++ b/net/netfilter/nfnetlink_acct.c @@ -238,29 +238,33 @@ static const struct nla_policy filter_policy[NFACCT_FILTER_MAX + 1] = { [NFACCT_FILTER_VALUE] = { .type = NLA_U32 }, }; -static struct nfacct_filter * -nfacct_filter_alloc(const struct nlattr * const attr) +static int nfnl_acct_start(struct netlink_callback *cb) { - struct nfacct_filter *filter; + const struct nlattr *const attr = cb->data; struct nlattr *tb[NFACCT_FILTER_MAX + 1]; + struct nfacct_filter *filter; int err; + if (!attr) + return 0; + err = nla_parse_nested(tb, NFACCT_FILTER_MAX, attr, filter_policy, NULL); if (err < 0) - return ERR_PTR(err); + return err; if (!tb[NFACCT_FILTER_MASK] || !tb[NFACCT_FILTER_VALUE]) - return ERR_PTR(-EINVAL); + return -EINVAL; filter = kzalloc(sizeof(struct nfacct_filter), GFP_KERNEL); if (!filter) - return ERR_PTR(-ENOMEM); + return -ENOMEM; filter->mask = ntohl(nla_get_be32(tb[NFACCT_FILTER_MASK])); filter->value = ntohl(nla_get_be32(tb[NFACCT_FILTER_VALUE])); + cb->data = filter; - return filter; + return 0; } static int nfnl_acct_get(struct net *net, struct sock *nfnl, @@ -275,18 +279,11 @@ static int nfnl_acct_get(struct net *net, struct sock *nfnl, if (nlh->nlmsg_flags & NLM_F_DUMP) { struct netlink_dump_control c = { .dump = nfnl_acct_dump, + .start = nfnl_acct_start, .done = nfnl_acct_done, + .data = (void *)tb[NFACCT_FILTER], }; - if (tb[NFACCT_FILTER]) { - struct nfacct_filter *filter; - - filter = nfacct_filter_alloc(tb[NFACCT_FILTER]); - if (IS_ERR(filter)) - return PTR_ERR(filter); - - c.data = filter; - } return netlink_dump_start(nfnl, skb, nlh, &c); } -- 2.7.4