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.gong...@huawei.com>
Cc: Herbert Xu <herb...@gondor.apana.org.au>
Cc: "Michael S. Tsirkin" <m...@redhat.com>
Cc: Jason Wang <jasow...@redhat.com>
Cc: "David S. Miller" <da...@davemloft.net>
Cc: virtualizat...@lists.linux-foundation.org
Cc: linux-ker...@vger.kernel.org
Reported-by: LABBE Corentin <cla...@baylibre.com>
Signed-off-by: Gonglei <arei.gong...@huawei.com>
Signed-off-by: Longpeng(Mike) <longpe...@huawei.com>
---
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
