[NETFILTER]: nfnetlink_queue: deobfuscate entry lookups
A queue entry lookup currently looks like this:
find_dequeue_entry -> __find_dequeue_entry ->
__find_entry -> cmpfn -> id_cmp
Use simple open-coded list walking and kill the cmpfn for
find_dequeue_entry. Instead add it to nfqnl_flush (after
similar cleanups) and use nfqnl_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/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index 74d5ed9..cb901cf 100644
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -171,7 +171,8 @@
return NULL;
}
-static void nfqnl_flush(struct nfqnl_instance *queue, int verdict);
+static void nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn,
+ unsigned long data);
static void
_instance_destroy2(struct nfqnl_instance *inst, int lock)
@@ -188,7 +189,7 @@
write_unlock_bh(&instances_lock);
/* then flush all pending skbs from the queue */
- nfqnl_flush(inst, NF_DROP);
+ nfqnl_flush(inst, NULL, 0);
/* and finally put the refcount */
instance_put(inst);
@@ -235,54 +236,6 @@
queue->queue_total++;
}
-/*
- * Find and return a queued entry matched by cmpfn, or return the last
- * entry if cmpfn is NULL.
- */
-static inline struct nfqnl_queue_entry *
-__find_entry(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn,
- unsigned long data)
-{
- struct nfqnl_queue_entry *entry;
-
- list_for_each_entry(entry, &queue->queue_list, list) {
- if (!cmpfn || cmpfn(entry, data))
- return entry;
- }
- return NULL;
-}
-
-static inline void
-__dequeue_entry(struct nfqnl_instance *q, struct nfqnl_queue_entry *entry)
-{
- list_del(&entry->list);
- q->queue_total--;
-}
-
-static inline struct nfqnl_queue_entry *
-__find_dequeue_entry(struct nfqnl_instance *queue,
- nfqnl_cmpfn cmpfn, unsigned long data)
-{
- struct nfqnl_queue_entry *entry;
-
- entry = __find_entry(queue, cmpfn, data);
- if (entry == NULL)
- return NULL;
-
- __dequeue_entry(queue, entry);
- return entry;
-}
-
-
-static inline void
-__nfqnl_flush(struct nfqnl_instance *queue, int verdict)
-{
- struct nfqnl_queue_entry *entry;
-
- while ((entry = __find_dequeue_entry(queue, NULL, 0)))
- issue_verdict(entry, verdict);
-}
-
static inline int
__nfqnl_set_mode(struct nfqnl_instance *queue,
unsigned char mode, unsigned int range)
@@ -313,23 +266,42 @@
}
static struct nfqnl_queue_entry *
-find_dequeue_entry(struct nfqnl_instance *queue,
- nfqnl_cmpfn cmpfn, unsigned long data)
+find_dequeue_entry(struct nfqnl_instance *queue, unsigned int id)
{
- struct nfqnl_queue_entry *entry;
+ struct nfqnl_queue_entry *entry = NULL, *i;
spin_lock_bh(&queue->lock);
- entry = __find_dequeue_entry(queue, cmpfn, data);
+
+ list_for_each_entry(i, &queue->queue_list, list) {
+ if (i->id == id) {
+ entry = i;
+ break;
+ }
+ }
+
+ if (entry) {
+ list_del(&entry->list);
+ queue->queue_total--;
+ }
+
spin_unlock_bh(&queue->lock);
return entry;
}
static void
-nfqnl_flush(struct nfqnl_instance *queue, int verdict)
+nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn, unsigned long data)
{
+ struct nfqnl_queue_entry *entry, *next;
+
spin_lock_bh(&queue->lock);
- __nfqnl_flush(queue, verdict);
+ list_for_each_entry_safe(entry, next, &queue->queue_list, list) {
+ if (!cmpfn || cmpfn(entry, data)) {
+ list_del(&entry->list);
+ queue->queue_total--;
+ issue_verdict(entry, NF_DROP);
+ }
+ }
spin_unlock_bh(&queue->lock);
}
@@ -644,12 +616,6 @@
return 0;
}
-static inline int
-id_cmp(struct nfqnl_queue_entry *e, unsigned long id)
-{
- return (id == e->id);
-}
-
static int
nfqnl_set_mode(struct nfqnl_instance *queue,
unsigned char mode, unsigned int range)
@@ -706,12 +672,8 @@
struct nfqnl_instance *inst;
struct hlist_head *head = &instance_table[i];
- hlist_for_each_entry(inst, tmp, head, hlist) {
- struct nfqnl_queue_entry *entry;
- while ((entry = find_dequeue_entry(inst, dev_cmp,
- ifindex)) != NULL)
- issue_verdict(entry, NF_DROP);
- }
+ hlist_for_each_entry(inst, tmp, head, hlist)
+ nfqnl_flush(inst, dev_cmp, ifindex);
}
read_unlock_bh(&instances_lock);
@@ -811,7 +773,7 @@
goto err_out_put;
}
- entry = find_dequeue_entry(queue, id_cmp, ntohl(vhdr->id));
+ entry = find_dequeue_entry(queue, ntohl(vhdr->id));
if (entry == NULL) {
err = -ENOENT;
goto err_out_put;