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 <arei.gonglei@xxxxxxxxxx> Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Cc: "Michael S. Tsirkin" <mst@xxxxxxxxxx> Cc: Jason Wang <jasowang@xxxxxxxxxx> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx> Cc: virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Reported-by: LABBE Corentin <clabbe@xxxxxxxxxxxx> Signed-off-by: Gonglei <arei.gonglei@xxxxxxxxxx> Signed-off-by: Longpeng(Mike) <longpeng2@xxxxxxxxxx> --- 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