net: properly release sk_frag.page
authorEric Dumazet <edumazet@google.com>
Wed, 15 Mar 2017 20:21:28 +0000 (13:21 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 30 Mar 2017 07:35:13 +0000 (09:35 +0200)
[ Upstream commit 22a0e18eac7a9e986fec76c60fa4a2926d1291e2 ]

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net/core/sock.c

index f4c0917e66b5f8cad1cec9a7b93e84b67cfe1006..9f4c4473156a3caa3b50831f6e9410aa295c1417 100644 (file)
@@ -1459,6 +1459,11 @@ void sk_destruct(struct sock *sk)
                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);
@@ -2691,11 +2696,6 @@ 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);