crypto: af_alg - Forbid bind(2) when nokey child sockets are present

[pandora-kernel.git] / crypto / af_alg.c

diff --git a/crypto/af_alg.c b/crypto/af_alg.c
index ac33d5f..68ec1ac 100644 (file)
--- a/crypto/af_alg.c
+++ b/crypto/af_alg.c
@@ -21,6 +21,7 @@
 #include <linux/module.h>
 #include <linux/net.h>
 #include <linux/rwsem.h>
+#include <linux/security.h>
 
 struct alg_type_list {
        const struct af_alg_type *type;
@@ -75,6 +76,8 @@ int af_alg_register_type(const struct af_alg_type *type)
                goto unlock;
 
        type->ops->owner = THIS_MODULE;
+       if (type->ops_nokey)
+               type->ops_nokey->owner = THIS_MODULE;
        node->type = type;
        list_add(&node->list, &alg_types);
        err = 0;
@@ -124,6 +127,26 @@ int af_alg_release(struct socket *sock)
 }
 EXPORT_SYMBOL_GPL(af_alg_release);
 
+void af_alg_release_parent(struct sock *sk)
+{
+       struct alg_sock *ask = alg_sk(sk);
+       unsigned int nokey = ask->nokey_refcnt;
+       bool last = nokey && !ask->refcnt;
+
+       sk = ask->parent;
+       ask = alg_sk(sk);
+
+       lock_sock(sk);
+       ask->nokey_refcnt -= nokey;
+       if (!last)
+               last = !--ask->refcnt;
+       release_sock(sk);
+
+       if (last)
+               sock_put(sk);
+}
+EXPORT_SYMBOL_GPL(af_alg_release_parent);
+
 static int alg_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 {
        struct sock *sk = sock->sk;
@@ -131,6 +154,7 @@ static int alg_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
        struct sockaddr_alg *sa = (void *)uaddr;
        const struct af_alg_type *type;
        void *private;
+       int err;
 
        if (sock->state == SS_CONNECTED)
                return -EINVAL;
@@ -156,16 +180,22 @@ static int alg_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
                return PTR_ERR(private);
        }
 
+       err = -EBUSY;
        lock_sock(sk);
+       if (ask->refcnt | ask->nokey_refcnt)
+               goto unlock;
 
        swap(ask->type, type);
        swap(ask->private, private);
 
+       err = 0;
+
+unlock:
        release_sock(sk);
 
        alg_do_release(type, private);
 
-       return 0;
+       return err;
 }
 
 static int alg_setkey(struct sock *sk, char __user *ukey,
@@ -198,11 +228,15 @@ static int alg_setsockopt(struct socket *sock, int level, int optname,
        struct sock *sk = sock->sk;
        struct alg_sock *ask = alg_sk(sk);
        const struct af_alg_type *type;
-       int err = -ENOPROTOOPT;
+       int err = -EBUSY;
 
        lock_sock(sk);
+       if (ask->refcnt)
+               goto unlock;
+
        type = ask->type;
 
+       err = -ENOPROTOOPT;
        if (level != SOL_ALG || !type)
                goto unlock;
 
@@ -227,6 +261,7 @@ int af_alg_accept(struct sock *sk, struct socket *newsock)
        struct alg_sock *ask = alg_sk(sk);
        const struct af_alg_type *type;
        struct sock *sk2;
+       unsigned int nokey;
        int err;
 
        lock_sock(sk);
@@ -243,22 +278,32 @@ int af_alg_accept(struct sock *sk, struct socket *newsock)
 
        sock_init_data(newsock, sk2);
        sock_graft(sk2, newsock);
+       security_sk_clone(sk, sk2);
 
        err = type->accept(ask->private, sk2);
-       if (err) {
-               sk_free(sk2);
+
+       nokey = err == -ENOKEY;
+       if (nokey && type->accept_nokey)
+               err = type->accept_nokey(ask->private, sk2);
+
+       if (err)
                goto unlock;
-       }
 
        sk2->sk_family = PF_ALG;
 
-       sock_hold(sk);
+       if (nokey || !ask->refcnt++)
+               sock_hold(sk);
+       ask->nokey_refcnt += nokey;
        alg_sk(sk2)->parent = sk;
        alg_sk(sk2)->type = type;
+       alg_sk(sk2)->nokey_refcnt = nokey;
 
        newsock->ops = type->ops;
        newsock->state = SS_CONNECTED;
 
+       if (nokey)
+               newsock->ops = type->ops_nokey;
+
        err = 0;
 
 unlock:
@@ -447,6 +492,9 @@ void af_alg_complete(struct crypto_async_request *req, int err)
 {
        struct af_alg_completion *completion = req->data;
 
+       if (err == -EINPROGRESS)
+               return;
+
        completion->err = err;
        complete(&completion->completion);
 }