diff options
Diffstat (limited to 'net/netfilter/nfnetlink.c')
-rw-r--r-- | net/netfilter/nfnetlink.c | 44 |
1 files changed, 41 insertions, 3 deletions
diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c index 03ead8a9e90c..4d0da7042aff 100644 --- a/net/netfilter/nfnetlink.c +++ b/net/netfilter/nfnetlink.c @@ -25,6 +25,7 @@ #include <linux/uaccess.h> #include <net/sock.h> #include <linux/init.h> +#include <linux/sched/signal.h> #include <net/netlink.h> #include <linux/netfilter/nfnetlink.h> @@ -37,6 +38,8 @@ MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_NETFILTER); rcu_dereference_protected(table[(id)].subsys, \ lockdep_nfnl_is_held((id))) +#define NFNL_MAX_ATTR_COUNT 32 + static struct { struct mutex mutex; const struct nfnetlink_subsystem __rcu *subsys; @@ -76,6 +79,13 @@ EXPORT_SYMBOL_GPL(lockdep_nfnl_is_held); int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n) { + u8 cb_id; + + /* Sanity-check attr_count size to avoid stack buffer overflow. */ + for (cb_id = 0; cb_id < n->cb_count; cb_id++) + if (WARN_ON(n->cb[cb_id].attr_count > NFNL_MAX_ATTR_COUNT)) + return -EINVAL; + nfnl_lock(n->subsys_id); if (table[n->subsys_id].subsys) { nfnl_unlock(n->subsys_id); @@ -185,11 +195,17 @@ replay: { int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); u8 cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type); - struct nlattr *cda[ss->cb[cb_id].attr_count + 1]; + struct nlattr *cda[NFNL_MAX_ATTR_COUNT + 1]; struct nlattr *attr = (void *)nlh + min_len; int attrlen = nlh->nlmsg_len - min_len; __u8 subsys_id = NFNL_SUBSYS_ID(type); + /* Sanity-check NFNL_MAX_ATTR_COUNT */ + if (ss->cb[cb_id].attr_count > NFNL_MAX_ATTR_COUNT) { + rcu_read_unlock(); + return -ENOMEM; + } + err = nla_parse(cda, ss->cb[cb_id].attr_count, attr, attrlen, ss->cb[cb_id].policy, extack); if (err < 0) { @@ -330,6 +346,13 @@ replay: while (skb->len >= nlmsg_total_size(0)) { int msglen, type; + if (fatal_signal_pending(current)) { + nfnl_err_reset(&err_list); + err = -EINTR; + status = NFNL_BATCH_FAILURE; + goto done; + } + memset(&extack, 0, sizeof(extack)); nlh = nlmsg_hdr(skb); err = 0; @@ -379,10 +402,16 @@ replay: { int min_len = nlmsg_total_size(sizeof(struct nfgenmsg)); u8 cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type); - struct nlattr *cda[ss->cb[cb_id].attr_count + 1]; + struct nlattr *cda[NFNL_MAX_ATTR_COUNT + 1]; struct nlattr *attr = (void *)nlh + min_len; int attrlen = nlh->nlmsg_len - min_len; + /* Sanity-check NFTA_MAX_ATTR */ + if (ss->cb[cb_id].attr_count > NFNL_MAX_ATTR_COUNT) { + err = -ENOMEM; + goto ack; + } + err = nla_parse(cda, ss->cb[cb_id].attr_count, attr, attrlen, ss->cb[cb_id].policy, NULL); if (err < 0) @@ -441,10 +470,19 @@ done: kfree_skb(skb); goto replay; } else if (status == NFNL_BATCH_DONE) { - ss->commit(net, oskb); + err = ss->commit(net, oskb); + if (err == -EAGAIN) { + status |= NFNL_BATCH_REPLAY; + goto done; + } else if (err) { + ss->abort(net, oskb); + netlink_ack(oskb, nlmsg_hdr(oskb), err, NULL); + } } else { ss->abort(net, oskb); } + if (ss->cleanup) + ss->cleanup(net); nfnl_err_deliver(&err_list, oskb); nfnl_unlock(subsys_id); |