From ec69bbfb9902c32a5c1492f2b1b8ad032a66d724 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Wed, 3 Feb 2016 21:39:24 +0800 Subject: [PATCH] crypto: algif_skcipher - Do not assume that req is unchanged The async path in algif_skcipher assumes that the crypto completion function will be called with the original request. This is not necessarily the case. In fact there is no need for this anyway since we already embed information into the request with struct skcipher_async_req. This patch adds a pointer to that struct and then passes it as the data to the callback function. Cc: stable@vger.kernel.org Signed-off-by: Herbert Xu Tested-by: Tadeusz Struk --- crypto/algif_skcipher.c | 64 +++++++++++++++++++---------------------- 1 file changed, 30 insertions(+), 34 deletions(-) diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c index 38c1aa89d3a0..ec07a864b9c5 100644 --- a/crypto/algif_skcipher.c +++ b/crypto/algif_skcipher.c @@ -65,18 +65,10 @@ struct skcipher_async_req { struct skcipher_async_rsgl first_sgl; struct list_head list; struct scatterlist *tsg; - char iv[]; + atomic_t *inflight; + struct skcipher_request req; }; -#define GET_SREQ(areq, ctx) (struct skcipher_async_req *)((char *)areq + \ - crypto_skcipher_reqsize(crypto_skcipher_reqtfm(&ctx->req))) - -#define GET_REQ_SIZE(ctx) \ - crypto_skcipher_reqsize(crypto_skcipher_reqtfm(&ctx->req)) - -#define GET_IV_SIZE(ctx) \ - crypto_skcipher_ivsize(crypto_skcipher_reqtfm(&ctx->req)) - #define MAX_SGL_ENTS ((4096 - sizeof(struct skcipher_sg_list)) / \ sizeof(struct scatterlist) - 1) @@ -102,15 +94,12 @@ static void skcipher_free_async_sgls(struct skcipher_async_req *sreq) static void skcipher_async_cb(struct crypto_async_request *req, int err) { - struct sock *sk = req->data; - struct alg_sock *ask = alg_sk(sk); - struct skcipher_ctx *ctx = ask->private; - struct skcipher_async_req *sreq = GET_SREQ(req, ctx); + struct skcipher_async_req *sreq = req->data; struct kiocb *iocb = sreq->iocb; - atomic_dec(&ctx->inflight); + atomic_dec(sreq->inflight); skcipher_free_async_sgls(sreq); - kfree(req); + kzfree(sreq); iocb->ki_complete(iocb, err, err); } @@ -509,37 +498,42 @@ static int skcipher_recvmsg_async(struct socket *sock, struct msghdr *msg, { struct sock *sk = sock->sk; struct alg_sock *ask = alg_sk(sk); + struct sock *psk = ask->parent; + struct alg_sock *pask = alg_sk(psk); struct skcipher_ctx *ctx = ask->private; + struct skcipher_tfm *skc = pask->private; + struct crypto_skcipher *tfm = skc->skcipher; struct skcipher_sg_list *sgl; struct scatterlist *sg; struct skcipher_async_req *sreq; struct skcipher_request *req; struct skcipher_async_rsgl *last_rsgl = NULL; unsigned int txbufs = 0, len = 0, tx_nents = skcipher_all_sg_nents(ctx); - unsigned int reqlen = sizeof(struct skcipher_async_req) + - GET_REQ_SIZE(ctx) + GET_IV_SIZE(ctx); + unsigned int reqsize = crypto_skcipher_reqsize(tfm); + unsigned int ivsize = crypto_skcipher_ivsize(tfm); int err = -ENOMEM; bool mark = false; + char *iv; + + sreq = kzalloc(sizeof(*sreq) + reqsize + ivsize, GFP_KERNEL); + if (unlikely(!sreq)) + goto out; + + req = &sreq->req; + iv = (char *)(req + 1) + reqsize; + sreq->iocb = msg->msg_iocb; + INIT_LIST_HEAD(&sreq->list); + sreq->inflight = &ctx->inflight; lock_sock(sk); - req = kmalloc(reqlen, GFP_KERNEL); - if (unlikely(!req)) - goto unlock; - - sreq = GET_SREQ(req, ctx); - sreq->iocb = msg->msg_iocb; - memset(&sreq->first_sgl, '\0', sizeof(struct skcipher_async_rsgl)); - INIT_LIST_HEAD(&sreq->list); sreq->tsg = kcalloc(tx_nents, sizeof(*sg), GFP_KERNEL); - if (unlikely(!sreq->tsg)) { - kfree(req); + if (unlikely(!sreq->tsg)) goto unlock; - } sg_init_table(sreq->tsg, tx_nents); - memcpy(sreq->iv, ctx->iv, GET_IV_SIZE(ctx)); - skcipher_request_set_tfm(req, crypto_skcipher_reqtfm(&ctx->req)); + memcpy(iv, ctx->iv, ivsize); + skcipher_request_set_tfm(req, tfm); skcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG, - skcipher_async_cb, sk); + skcipher_async_cb, sreq); while (iov_iter_count(&msg->msg_iter)) { struct skcipher_async_rsgl *rsgl; @@ -615,20 +609,22 @@ static int skcipher_recvmsg_async(struct socket *sock, struct msghdr *msg, sg_mark_end(sreq->tsg + txbufs - 1); skcipher_request_set_crypt(req, sreq->tsg, sreq->first_sgl.sgl.sg, - len, sreq->iv); + len, iv); err = ctx->enc ? crypto_skcipher_encrypt(req) : crypto_skcipher_decrypt(req); if (err == -EINPROGRESS) { atomic_inc(&ctx->inflight); err = -EIOCBQUEUED; + sreq = NULL; goto unlock; } free: skcipher_free_async_sgls(sreq); - kfree(req); unlock: skcipher_wmem_wakeup(sk); release_sock(sk); + kzfree(sreq); +out: return err; }