net: properly release sk_frag.page
authorEric Dumazet <edumazet@google.com>
Wed, 15 Mar 2017 20:21:28 +0000 (13:21 -0700)
committerDavid S. Miller <davem@davemloft.net>
Wed, 15 Mar 2017 22:37:45 +0000 (15:37 -0700)
I mistakenly added the code to release sk->sk_frag in
sk_common_release() instead of sk_destruct()

TCP sockets using sk->sk_allocation == GFP_ATOMIC do no call
sk_common_release() at close time, thus leaking one (order-3) page.

iSCSI is using such sockets.

Fixes: 5640f7685831 ("net: use a per task frag allocator")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/core/sock.c

index a96d5f7a5734a52dfd6a2df8490c7bd7f5f6599a..acb0d413749968f24ffc7df3e366b095f80e10f4 100644 (file)
@@ -1442,6 +1442,11 @@ static void __sk_destruct(struct rcu_head *head)
                pr_debug("%s: optmem leakage (%d bytes) detected\n",
                         __func__, atomic_read(&sk->sk_omem_alloc));
 
+       if (sk->sk_frag.page) {
+               put_page(sk->sk_frag.page);
+               sk->sk_frag.page = NULL;
+       }
+
        if (sk->sk_peer_cred)
                put_cred(sk->sk_peer_cred);
        put_pid(sk->sk_peer_pid);
@@ -2787,11 +2792,6 @@ void sk_common_release(struct sock *sk)
 
        sk_refcnt_debug_release(sk);
 
-       if (sk->sk_frag.page) {
-               put_page(sk->sk_frag.page);
-               sk->sk_frag.page = NULL;
-       }
-
        sock_put(sk);
 }
 EXPORT_SYMBOL(sk_common_release);