From e6534aebb26e32fbab14df9c713c65e8507d17e4 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Mon, 10 Apr 2017 17:59:07 +0800 Subject: [PATCH] crypto: algif_aead - Fix bogus request dereference in completion function The algif_aead completion function tries to deduce the aead_request from the crypto_async_request argument. This is broken because the API does not guarantee that the same request will be pased to the completion function. Only the value of req->data can be used in the completion function. This patch fixes it by storing a pointer to sk in areq and using that instead of passing in sk through req->data. Fixes: 83094e5e9e49 ("crypto: af_alg - add async support to...") Cc: Signed-off-by: Herbert Xu --- crypto/algif_aead.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/crypto/algif_aead.c b/crypto/algif_aead.c index 5a8053758657..ef59d9926ee9 100644 --- a/crypto/algif_aead.c +++ b/crypto/algif_aead.c @@ -40,6 +40,7 @@ struct aead_async_req { struct aead_async_rsgl first_rsgl; struct list_head list; struct kiocb *iocb; + struct sock *sk; unsigned int tsgls; char iv[]; }; @@ -379,12 +380,10 @@ unlock: static void aead_async_cb(struct crypto_async_request *_req, int err) { - struct sock *sk = _req->data; - struct alg_sock *ask = alg_sk(sk); - struct aead_ctx *ctx = ask->private; - struct crypto_aead *tfm = crypto_aead_reqtfm(&ctx->aead_req); - struct aead_request *req = aead_request_cast(_req); + struct aead_request *req = _req->data; + struct crypto_aead *tfm = crypto_aead_reqtfm(req); struct aead_async_req *areq = GET_ASYM_REQ(req, tfm); + struct sock *sk = areq->sk; struct scatterlist *sg = areq->tsgl; struct aead_async_rsgl *rsgl; struct kiocb *iocb = areq->iocb; @@ -447,11 +446,12 @@ static int aead_recvmsg_async(struct socket *sock, struct msghdr *msg, memset(&areq->first_rsgl, '\0', sizeof(areq->first_rsgl)); INIT_LIST_HEAD(&areq->list); areq->iocb = msg->msg_iocb; + areq->sk = sk; memcpy(areq->iv, ctx->iv, crypto_aead_ivsize(tfm)); aead_request_set_tfm(req, tfm); aead_request_set_ad(req, ctx->aead_assoclen); aead_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG, - aead_async_cb, sk); + aead_async_cb, req); used -= ctx->aead_assoclen; /* take over all tx sgls from ctx */ -- 2.20.1