On 02/21/2016 05:40 PM, Milan Broz wrote:
> On 02/20/2016 03:33 PM, Thomas D. wrote:
>> Hi,
>>
>> FYI: v3.10.97, v3.14.61 and 3.18.27 are also affected.
>>
>> v4.3.6 works. Looks like the patch set is only compatible with >=linux-4.3.
>>
>> v3.12.54 works because it doesn't contain the patch in question.
>
> Hi,
>
> indeed, because whoever backported this patchset skipped two patches
> from series (because of skcipher interface file was introduced later).
Ping?
I always thought that breaking userspace is not the way mainline kernel
operates and here we break even stable tree...
Anyone planning to release new kernel version with properly backported patches?
There is already a lot of downstream distro bugs reported.
Thanks,
Milan
>
> I tried to backport it (on 4.1.18 tree, see patch below) and it fixes the
> problem
> for me.
>
> Anyway, it is just quick test what is the problem, patch need proper review or
> backport from someone who knows the code better.
>
> I will release stable cryptsetup soon that will work with new kernel even
> without
> this patch but I would strongly recommend that stable kernels get these
> compatibility
> backports as well to avoid breaking existing userspace.
>
> Thanks,
> Milan
> -
>
> This patch backports missing parts of crypto API compatibility changes:
>
> dd504589577d8e8e70f51f997ad487a4cb6c026f
> crypto: algif_skcipher - Require setkey before accept(2)
>
> a0fa2d037129a9849918a92d91b79ed6c7bd2818
> crypto: algif_skcipher - Add nokey compatibility path
>
> --- crypto/algif_skcipher.c.orig 2016-02-21 16:44:27.172312990 +0100
> +++ crypto/algif_skcipher.c 2016-02-21 17:03:58.555785347 +0100
> @@ -31,6 +31,11 @@
> struct scatterlist sg[0];
> };
>
> +struct skcipher_tfm {
> + struct crypto_ablkcipher *skcipher;
> + bool has_key;
> +};
> +
> struct skcipher_ctx {
> struct list_head tsgl;
> struct af_alg_sgl rsgl;
> @@ -750,19 +755,136 @@
> .poll = skcipher_poll,
> };
>
> +static int skcipher_check_key(struct socket *sock)
> +{
> + int err;
> + struct sock *psk;
> + struct alg_sock *pask;
> + struct skcipher_tfm *tfm;
> + struct sock *sk = sock->sk;
> + struct alg_sock *ask = alg_sk(sk);
> +
> + if (ask->refcnt)
> + return 0;
> +
> + psk = ask->parent;
> + pask = alg_sk(ask->parent);
> + tfm = pask->private;
> +
> + err = -ENOKEY;
> + lock_sock(psk);
> + if (!tfm->has_key)
> + goto unlock;
> +
> + if (!pask->refcnt++)
> + sock_hold(psk);
> +
> + ask->refcnt = 1;
> + sock_put(psk);
> +
> + err = 0;
> +
> +unlock:
> + release_sock(psk);
> +
> + return err;
> +}
> +
> +static int skcipher_sendmsg_nokey(struct socket *sock, struct msghdr *msg,
> + size_t size)
> +{
> + int err;
> +
> + err = skcipher_check_key(sock);
> + if (err)
> + return err;
> +
> + return skcipher_sendmsg(sock, msg, size);
> +}
> +
> +static ssize_t skcipher_sendpage_nokey(struct socket *sock, struct page
> *page,
> +int offset, size_t size, int flags)
> +{
> + int err;
> +
> + err = skcipher_check_key(sock);
> + if (err)
> + return err;
> +
> + return skcipher_sendpage(sock, page, offset, size, flags);
> +}
> +
> +static int skcipher_recvmsg_nokey(struct socket *sock, struct msghdr *msg,
> + size_t ignored, int flags)
> +{
> + int err;
> +
> + err = skcipher_check_key(sock);
> + if (err)
> + return err;
> +
> + return skcipher_recvmsg(sock, msg, ignored, flags);
> +}
> +
> +static struct proto_ops algif_skcipher_ops_nokey = {
> + .family = PF_ALG,
> +
> + .connect= sock_no_connect,
> + .socketpair = sock_no_socketpair,
> + .getname= sock_no_getname,
> + .ioctl = sock_no_ioctl,
> + .listen = sock_no_listen,
> + .shutdown = sock_no_shutdown,
> + .getsockopt = sock_no_getsockopt,
> + .mmap = sock_no_mmap,
> + .bind = sock_no_bind,
> + .accept = sock_no_accept,
> + .setsockopt = sock_no_setsockopt,
> +
> + .release= af_alg_release,
> + .sendmsg= skcipher_sendmsg_nokey,
> + .sendpage = skcipher_sendpage_nokey,
> + .recvmsg= skcipher_recvmsg_nokey,
> + .poll = skcipher_poll,
> +};
> +
> static void *skcipher_bind(const char *name, u32 type, u32 mask)
> {
> - return crypto_alloc_ablkcipher(name, type, mask);
> + struct skcipher_tfm *tfm;
> + struct crypto_ablkcipher *skcipher;
> +
> + tfm = kzalloc(sizeof(*tfm), GFP_KERNEL);
> + if (!tfm)
> + return ERR_PTR(-ENOMEM);
> +
> + skcipher = crypto_alloc_ablkcipher(name,
