[NETFILTER]: ip_queue: deobfuscate entry lookups
A queue entry lookup currently looks like this:
ipq_find_dequeue_entry -> __ipq_find_dequeue_entry ->
__ipq_find_entry -> cmpfn -> id_cmp
Use simple open-coded list walking and kill the cmpfn for
ipq_find_dequeue_entry. Instead add it to ipq_flush (after
similar cleanups) and use ipq_flush for both complete flushes
and flushing entries related to a device.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/netfilter/ip_queue.c b/net/ipv4/netfilter/ip_queue.c
index 9e72246..df2957c 100644
--- a/net/ipv4/netfilter/ip_queue.c
+++ b/net/ipv4/netfilter/ip_queue.c
@@ -77,52 +77,6 @@
queue_total++;
}
-/*
- * Find and return a queued entry matched by cmpfn, or return the last
- * entry if cmpfn is NULL.
- */
-static inline struct ipq_queue_entry *
-__ipq_find_entry(ipq_cmpfn cmpfn, unsigned long data)
-{
- struct ipq_queue_entry *entry;
-
- list_for_each_entry(entry, &queue_list, list) {
- if (!cmpfn || cmpfn(entry, data))
- return entry;
- }
- return NULL;
-}
-
-static inline void
-__ipq_dequeue_entry(struct ipq_queue_entry *entry)
-{
- list_del(&entry->list);
- queue_total--;
-}
-
-static inline struct ipq_queue_entry *
-__ipq_find_dequeue_entry(ipq_cmpfn cmpfn, unsigned long data)
-{
- struct ipq_queue_entry *entry;
-
- entry = __ipq_find_entry(cmpfn, data);
- if (entry == NULL)
- return NULL;
-
- __ipq_dequeue_entry(entry);
- return entry;
-}
-
-
-static inline void
-__ipq_flush(int verdict)
-{
- struct ipq_queue_entry *entry;
-
- while ((entry = __ipq_find_dequeue_entry(NULL, 0)))
- ipq_issue_verdict(entry, verdict);
-}
-
static inline int
__ipq_set_mode(unsigned char mode, unsigned int range)
{
@@ -149,31 +103,59 @@
return status;
}
+static void __ipq_flush(ipq_cmpfn cmpfn, unsigned long data);
+
static inline void
__ipq_reset(void)
{
peer_pid = 0;
net_disable_timestamp();
__ipq_set_mode(IPQ_COPY_NONE, 0);
- __ipq_flush(NF_DROP);
+ __ipq_flush(NULL, 0);
}
static struct ipq_queue_entry *
-ipq_find_dequeue_entry(ipq_cmpfn cmpfn, unsigned long data)
+ipq_find_dequeue_entry(unsigned long id)
{
- struct ipq_queue_entry *entry;
+ struct ipq_queue_entry *entry = NULL, *i;
write_lock_bh(&queue_lock);
- entry = __ipq_find_dequeue_entry(cmpfn, data);
+
+ list_for_each_entry(i, &queue_list, list) {
+ if ((unsigned long)i == id) {
+ entry = i;
+ break;
+ }
+ }
+
+ if (entry) {
+ list_del(&entry->list);
+ queue_total--;
+ }
+
write_unlock_bh(&queue_lock);
return entry;
}
static void
-ipq_flush(int verdict)
+__ipq_flush(ipq_cmpfn cmpfn, unsigned long data)
+{
+ struct ipq_queue_entry *entry, *next;
+
+ list_for_each_entry_safe(entry, next, &queue_list, list) {
+ if (!cmpfn || cmpfn(entry, data)) {
+ list_del(&entry->list);
+ queue_total--;
+ ipq_issue_verdict(entry, NF_DROP);
+ }
+ }
+}
+
+static void
+ipq_flush(ipq_cmpfn cmpfn, unsigned long data)
{
write_lock_bh(&queue_lock);
- __ipq_flush(verdict);
+ __ipq_flush(cmpfn, data);
write_unlock_bh(&queue_lock);
}
@@ -367,12 +349,6 @@
return 0;
}
-static inline int
-id_cmp(struct ipq_queue_entry *e, unsigned long id)
-{
- return (id == (unsigned long )e);
-}
-
static int
ipq_set_verdict(struct ipq_verdict_msg *vmsg, unsigned int len)
{
@@ -381,7 +357,7 @@
if (vmsg->value > NF_MAX_VERDICT)
return -EINVAL;
- entry = ipq_find_dequeue_entry(id_cmp, vmsg->id);
+ entry = ipq_find_dequeue_entry(vmsg->id);
if (entry == NULL)
return -ENOENT;
else {
@@ -460,10 +436,7 @@
static void
ipq_dev_drop(int ifindex)
{
- struct ipq_queue_entry *entry;
-
- while ((entry = ipq_find_dequeue_entry(dev_cmp, ifindex)) != NULL)
- ipq_issue_verdict(entry, NF_DROP);
+ ipq_flush(dev_cmp, ifindex);
}
#define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0)
@@ -699,7 +672,7 @@
{
nf_unregister_queue_handlers(&nfqh);
synchronize_net();
- ipq_flush(NF_DROP);
+ ipq_flush(NULL, 0);
unregister_sysctl_table(ipq_sysctl_header);
unregister_netdevice_notifier(&ipq_dev_notifier);