From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Longpeng(Mike)" Subject: [PATCH 1/2] crypto: virtio: fix src/dst scatterlist calculation Date: Mon, 25 May 2020 08:56:26 +0800 Message-ID: <20200525005627.707-2-longpeng2@huawei.com> References: <20200525005627.707-1-longpeng2@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Return-path: In-Reply-To: <20200525005627.707-1-longpeng2@huawei.com> Sender: linux-crypto-owner@vger.kernel.org To: linux-crypto@vger.kernel.org Cc: "Longpeng(Mike)" , Gonglei , Herbert Xu , "Michael S. Tsirkin" , Jason Wang , "David S. Miller" , virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, LABBE Corentin List-Id: virtualization@lists.linuxfoundation.org The system will crash when we insmod crypto/tcrypt.ko whit mode=38. Usually the next entry of one sg will be @sg@ + 1, but if this sg element is part of a chained scatterlist, it could jump to the start of a new scatterlist array. Let's fix it by sg_next() on calculation of src/dst scatterlist. BTW I add a check for sg_nents_for_len() its return value since sg_nents_for_len() function could fail. Cc: Gonglei Cc: Herbert Xu Cc: "Michael S. Tsirkin" Cc: Jason Wang Cc: "David S. Miller" Cc: virtualization@lists.linux-foundation.org Cc: linux-kernel@vger.kernel.org Reported-by: LABBE Corentin Signed-off-by: Gonglei Signed-off-by: Longpeng(Mike) --- drivers/crypto/virtio/virtio_crypto_algs.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/drivers/crypto/virtio/virtio_crypto_algs.c b/drivers/crypto/virtio/virtio_crypto_algs.c index 372babb44112..2fa1129f96d6 100644 --- a/drivers/crypto/virtio/virtio_crypto_algs.c +++ b/drivers/crypto/virtio/virtio_crypto_algs.c @@ -359,8 +359,14 @@ __virtio_crypto_skcipher_do_req(struct virtio_crypto_sym_request *vc_sym_req, unsigned int num_out = 0, num_in = 0; int sg_total; uint8_t *iv; + struct scatterlist *sg; src_nents = sg_nents_for_len(req->src, req->cryptlen); + if (src_nents < 0) { + pr_err("Invalid number of src SG.\n"); + return src_nents; + } + dst_nents = sg_nents(req->dst); pr_debug("virtio_crypto: Number of sgs (src_nents: %d, dst_nents: %d)\n", @@ -446,12 +452,12 @@ __virtio_crypto_skcipher_do_req(struct virtio_crypto_sym_request *vc_sym_req, vc_sym_req->iv = iv; /* Source data */ - for (i = 0; i < src_nents; i++) - sgs[num_out++] = &req->src[i]; + for (sg = req->src, i = 0; sg && i < src_nents; sg = sg_next(sg), i++) + sgs[num_out++] = sg; /* Destination data */ - for (i = 0; i < dst_nents; i++) - sgs[num_out + num_in++] = &req->dst[i]; + for (sg = req->dst, i = 0; sg && i < dst_nents; sg = sg_next(sg), i++) + sgs[num_out + num_in++] = sg; /* Status */ sg_init_one(&status_sg, &vc_req->status, sizeof(vc_req->status)); -- 2.17.1