tcp/dccp: use rcu locking in inet_diag_find_one_icsk()
RX packet processing holds rcu_read_lock(), so we can remove
pairs of rcu_read_lock()/rcu_read_unlock() in lookup functions
if inet_diag also holds rcu before calling them.
This is needed anyway as __inet_lookup_listener() and
inet6_lookup_listener() will soon no longer increment
refcount on the found listener.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
index 5fdb02f..ea8df52 100644
--- a/net/ipv4/inet_diag.c
+++ b/net/ipv4/inet_diag.c
@@ -356,6 +356,7 @@
{
struct sock *sk;
+ rcu_read_lock();
if (req->sdiag_family == AF_INET)
sk = inet_lookup(net, hashinfo, NULL, 0, req->id.idiag_dst[0],
req->id.idiag_dport, req->id.idiag_src[0],
@@ -376,9 +377,11 @@
req->id.idiag_if);
}
#endif
- else
+ else {
+ rcu_read_unlock();
return ERR_PTR(-EINVAL);
-
+ }
+ rcu_read_unlock();
if (!sk)
return ERR_PTR(-ENOENT);
diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
index bc68ece..387338d 100644
--- a/net/ipv4/inet_hashtables.c
+++ b/net/ipv4/inet_hashtables.c
@@ -220,7 +220,6 @@
bool select_ok = true;
u32 phash = 0;
- rcu_read_lock();
begin:
result = NULL;
hiscore = 0;
@@ -269,7 +268,6 @@
goto begin;
}
}
- rcu_read_unlock();
return result;
}
EXPORT_SYMBOL_GPL(__inet_lookup_listener);
@@ -312,7 +310,6 @@
unsigned int slot = hash & hashinfo->ehash_mask;
struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
- rcu_read_lock();
begin:
sk_nulls_for_each_rcu(sk, node, &head->chain) {
if (sk->sk_hash != hash)
@@ -339,7 +336,6 @@
out:
sk = NULL;
found:
- rcu_read_unlock();
return sk;
}
EXPORT_SYMBOL_GPL(__inet_lookup_established);
diff --git a/net/ipv6/inet6_hashtables.c b/net/ipv6/inet6_hashtables.c
index d253f32..e6ef6ce1 100644
--- a/net/ipv6/inet6_hashtables.c
+++ b/net/ipv6/inet6_hashtables.c
@@ -69,7 +69,6 @@
struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
- rcu_read_lock();
begin:
sk_nulls_for_each_rcu(sk, node, &head->chain) {
if (sk->sk_hash != hash)
@@ -90,7 +89,6 @@
out:
sk = NULL;
found:
- rcu_read_unlock();
return sk;
}
EXPORT_SYMBOL(__inet6_lookup_established);
@@ -138,7 +136,6 @@
unsigned int hash = inet_lhashfn(net, hnum);
struct inet_listen_hashbucket *ilb = &hashinfo->listening_hash[hash];
- rcu_read_lock();
begin:
result = NULL;
hiscore = 0;
@@ -187,7 +184,6 @@
goto begin;
}
}
- rcu_read_unlock();
return result;
}
EXPORT_SYMBOL_GPL(inet6_lookup_listener);