vhost/crypto: fix possible out of bound access

This patch fixes a out of bound access possbility in vhost
crypto. Originally the incorrect next descriptor index may
cause the library read invalid memory content and crash
the application.

Fixes: 3bb595ecd682 ("vhost/crypto: add request handler")
Cc: stable@dpdk.org
Signed-off-by: Fan Zhang <roy.fan.zhang@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>

diff --git a/lib/librte_vhost/vhost_crypto.c b/lib/librte_vhost/vhost_crypto.c
index e12458c..ebf26f0 100644 (file)
--- a/lib/librte_vhost/vhost_crypto.c
+++ b/lib/librte_vhost/vhost_crypto.c
@@ -468,13 +468,13 @@ vhost_crypto_msg_post_handler(int vid, void *msg)
 
 static __rte_always_inline struct vring_desc *
 find_write_desc(struct vring_desc *head, struct vring_desc *desc,
-               uint32_t *nb_descs)
+               uint32_t *nb_descs, uint32_t vq_size)
 {
        if (desc->flags & VRING_DESC_F_WRITE)
                return desc;
 
        while (desc->flags & VRING_DESC_F_NEXT) {
-               if (unlikely(*nb_descs == 0))
+               if (unlikely(*nb_descs == 0 || desc->next >= vq_size))
                        return NULL;
                (*nb_descs)--;
 
@@ -488,13 +488,13 @@ find_write_desc(struct vring_desc *head, struct vring_desc *desc,
 
 static struct virtio_crypto_inhdr *
 reach_inhdr(struct vhost_crypto_data_req *vc_req, struct vring_desc *desc,
-               uint32_t *nb_descs)
+               uint32_t *nb_descs, uint32_t vq_size)
 {
        uint64_t dlen;
        struct virtio_crypto_inhdr *inhdr;
 
        while (desc->flags & VRING_DESC_F_NEXT) {
-               if (unlikely(*nb_descs == 0))
+               if (unlikely(*nb_descs == 0 || desc->next >= vq_size))
                        return NULL;
                (*nb_descs)--;
                desc = &vc_req->head[desc->next];
@@ -511,14 +511,14 @@ reach_inhdr(struct vhost_crypto_data_req *vc_req, struct vring_desc *desc,
 
 static __rte_always_inline int
 move_desc(struct vring_desc *head, struct vring_desc **cur_desc,
-               uint32_t size, uint32_t *nb_descs)
+               uint32_t size, uint32_t *nb_descs, uint32_t vq_size)
 {
        struct vring_desc *desc = *cur_desc;
        int left = size - desc->len;
 
        while ((desc->flags & VRING_DESC_F_NEXT) && left > 0) {
                (*nb_descs)--;
-               if (unlikely(*nb_descs == 0))
+               if (unlikely(*nb_descs == 0 || desc->next >= vq_size))
                        return -1;
 
                desc = &head[desc->next];
@@ -531,8 +531,12 @@ move_desc(struct vring_desc *head, struct vring_desc **cur_desc,
 
        if (unlikely(*nb_descs == 0))
                *cur_desc = NULL;
-       else
+       else {
+               if (unlikely(desc->next >= vq_size))
+                       return -1;
                *cur_desc = &head[desc->next];
+       }
+
        return 0;
 }
 
@@ -554,7 +558,8 @@ get_data_ptr(struct vhost_crypto_data_req *vc_req, struct vring_desc *cur_desc,
 
 static int
 copy_data(void *dst_data, struct vhost_crypto_data_req *vc_req,
-               struct vring_desc **cur_desc, uint32_t size, uint32_t *nb_descs)
+               struct vring_desc **cur_desc, uint32_t size,
+               uint32_t *nb_descs, uint32_t vq_size)
 {
        struct vring_desc *desc = *cur_desc;
        uint64_t remain, addr, dlen, len;
@@ -596,7 +601,7 @@ copy_data(void *dst_data, struct vhost_crypto_data_req *vc_req,
        left -= to_copy;
 
        while ((desc->flags & VRING_DESC_F_NEXT) && left > 0) {
-               if (unlikely(*nb_descs == 0)) {
+               if (unlikely(*nb_descs == 0 || desc->next >= vq_size)) {
                        VC_LOG_ERR("Invalid descriptors");
                        return -1;
                }
@@ -646,8 +651,11 @@ copy_data(void *dst_data, struct vhost_crypto_data_req *vc_req,
 
        if (unlikely(*nb_descs == 0))
                *cur_desc = NULL;
-       else
+       else {
+               if (unlikely(desc->next >= vq_size))
+                       return -1;
                *cur_desc = &vc_req->head[desc->next];
+       }
 
        return 0;
 }
@@ -658,7 +666,6 @@ write_back_data(struct vhost_crypto_data_req *vc_req)
        struct vhost_crypto_writeback_data *wb_data = vc_req->wb, *wb_last;
 
        while (wb_data) {
-               rte_prefetch0(wb_data->next);
                rte_memcpy(wb_data->dst, wb_data->src, wb_data->len);
                wb_last = wb_data;
                wb_data = wb_data->next;
@@ -708,7 +715,7 @@ prepare_write_back_data(struct vhost_crypto_data_req *vc_req,
                uint8_t *src,
                uint32_t offset,
                uint64_t write_back_len,
-               uint32_t *nb_descs)
+               uint32_t *nb_descs, uint32_t vq_size)
 {
        struct vhost_crypto_writeback_data *wb_data, *head;
        struct vring_desc *desc = *cur_desc;
@@ -755,7 +762,7 @@ prepare_write_back_data(struct vhost_crypto_data_req *vc_req,
                offset -= desc->len;
 
        while (write_back_len) {
-               if (unlikely(*nb_descs == 0)) {
+               if (unlikely(*nb_descs == 0 || desc->next >= vq_size)) {
                        VC_LOG_ERR("Invalid descriptors");
                        goto error_exit;
                }
@@ -802,8 +809,11 @@ prepare_write_back_data(struct vhost_crypto_data_req *vc_req,
 
        if (unlikely(*nb_descs == 0))
                *cur_desc = NULL;
-       else
+       else {
+               if (unlikely(desc->next >= vq_size))
+                       goto error_exit;
                *cur_desc = &vc_req->head[desc->next];
+       }
 
        *end_wb_data = wb_data;
 
@@ -821,7 +831,7 @@ prepare_sym_cipher_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
                struct vhost_crypto_data_req *vc_req,
                struct virtio_crypto_cipher_data_req *cipher,
                struct vring_desc *cur_desc,
-               uint32_t *nb_descs)
+               uint32_t *nb_descs, uint32_t vq_size)
 {
        struct vring_desc *desc = cur_desc;
        struct vhost_crypto_writeback_data *ewb = NULL;
@@ -832,7 +842,7 @@ prepare_sym_cipher_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
        /* prepare */
        /* iv */
        if (unlikely(copy_data(iv_data, vc_req, &desc, cipher->para.iv_len,
-                       nb_descs) < 0)) {
+                       nb_descs, vq_size) < 0)) {
                ret = VIRTIO_CRYPTO_BADMSG;
                goto error_exit;
        }
@@ -852,7 +862,8 @@ prepare_sym_cipher_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
                }
 
                if (unlikely(move_desc(vc_req->head, &desc,
-                               cipher->para.src_data_len, nb_descs) < 0)) {
+                               cipher->para.src_data_len, nb_descs,
+                               vq_size) < 0)) {
                        VC_LOG_ERR("Incorrect descriptor");
                        ret = VIRTIO_CRYPTO_ERR;
                        goto error_exit;
@@ -870,7 +881,7 @@ prepare_sym_cipher_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
                }
                if (unlikely(copy_data(rte_pktmbuf_mtod(m_src, uint8_t *),
                                vc_req, &desc, cipher->para.src_data_len,
-                               nb_descs) < 0)) {
+                               nb_descs, vq_size) < 0)) {
                        ret = VIRTIO_CRYPTO_BADMSG;
                        goto error_exit;
                }
@@ -881,7 +892,7 @@ prepare_sym_cipher_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
        }
 
        /* dst */
-       desc = find_write_desc(vc_req->head, desc, nb_descs);
+       desc = find_write_desc(vc_req->head, desc, nb_descs, vq_size);
        if (unlikely(!desc)) {
                VC_LOG_ERR("Cannot find write location");
                ret = VIRTIO_CRYPTO_BADMSG;
@@ -900,7 +911,8 @@ prepare_sym_cipher_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
                }
 
                if (unlikely(move_desc(vc_req->head, &desc,
-                               cipher->para.dst_data_len, nb_descs) < 0)) {
+                               cipher->para.dst_data_len,
+                               nb_descs, vq_size) < 0)) {
                        VC_LOG_ERR("Incorrect descriptor");
                        ret = VIRTIO_CRYPTO_ERR;
                        goto error_exit;
@@ -911,7 +923,7 @@ prepare_sym_cipher_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
        case RTE_VHOST_CRYPTO_ZERO_COPY_DISABLE:
                vc_req->wb = prepare_write_back_data(vc_req, &desc, &ewb,
                                rte_pktmbuf_mtod(m_src, uint8_t *), 0,
-                               cipher->para.dst_data_len, nb_descs);
+                               cipher->para.dst_data_len, nb_descs, vq_size);
                if (unlikely(vc_req->wb == NULL)) {
                        ret = VIRTIO_CRYPTO_ERR;
                        goto error_exit;
@@ -954,7 +966,7 @@ prepare_sym_chain_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
                struct vhost_crypto_data_req *vc_req,
                struct virtio_crypto_alg_chain_data_req *chain,
                struct vring_desc *cur_desc,
-               uint32_t *nb_descs)
+               uint32_t *nb_descs, uint32_t vq_size)
 {
        struct vring_desc *desc = cur_desc, *digest_desc;
        struct vhost_crypto_writeback_data *ewb = NULL, *ewb2 = NULL;
@@ -967,7 +979,7 @@ prepare_sym_chain_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
        /* prepare */
        /* iv */
        if (unlikely(copy_data(iv_data, vc_req, &desc,
-                       chain->para.iv_len, nb_descs) < 0)) {
+                       chain->para.iv_len, nb_descs, vq_size) < 0)) {
                ret = VIRTIO_CRYPTO_BADMSG;
                goto error_exit;
        }
@@ -988,7 +1000,8 @@ prepare_sym_chain_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
                }
 
                if (unlikely(move_desc(vc_req->head, &desc,
-                               chain->para.src_data_len, nb_descs) < 0)) {
+                               chain->para.src_data_len,
+                               nb_descs, vq_size) < 0)) {
                        VC_LOG_ERR("Incorrect descriptor");
                        ret = VIRTIO_CRYPTO_ERR;
                        goto error_exit;
@@ -1005,7 +1018,7 @@ prepare_sym_chain_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
                }
                if (unlikely(copy_data(rte_pktmbuf_mtod(m_src, uint8_t *),
                                vc_req, &desc, chain->para.src_data_len,
-                               nb_descs)) < 0) {
+                               nb_descs, vq_size)) < 0) {
                        ret = VIRTIO_CRYPTO_BADMSG;
                        goto error_exit;
                }
@@ -1017,7 +1030,7 @@ prepare_sym_chain_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
        }
 
        /* dst */
-       desc = find_write_desc(vc_req->head, desc, nb_descs);
+       desc = find_write_desc(vc_req->head, desc, nb_descs, vq_size);
        if (unlikely(!desc)) {
                VC_LOG_ERR("Cannot find write location");
                ret = VIRTIO_CRYPTO_BADMSG;
@@ -1036,7 +1049,8 @@ prepare_sym_chain_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
                }
 
                if (unlikely(move_desc(vc_req->head, &desc,
-                               chain->para.dst_data_len, nb_descs) < 0)) {
+                               chain->para.dst_data_len,
+                               nb_descs, vq_size) < 0)) {
                        VC_LOG_ERR("Incorrect descriptor");
                        ret = VIRTIO_CRYPTO_ERR;
                        goto error_exit;
@@ -1053,7 +1067,8 @@ prepare_sym_chain_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
                }
 
                if (unlikely(move_desc(vc_req->head, &desc,
-                               chain->para.hash_result_len, nb_descs) < 0)) {
+                               chain->para.hash_result_len,
+                               nb_descs, vq_size) < 0)) {
                        VC_LOG_ERR("Incorrect descriptor");
                        ret = VIRTIO_CRYPTO_ERR;
                        goto error_exit;
@@ -1065,7 +1080,8 @@ prepare_sym_chain_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
                                rte_pktmbuf_mtod(m_src, uint8_t *),
                                chain->para.cipher_start_src_offset,
                                chain->para.dst_data_len -
-                               chain->para.cipher_start_src_offset, nb_descs);
+                               chain->para.cipher_start_src_offset,
+                               nb_descs, vq_size);
                if (unlikely(vc_req->wb == NULL)) {
                        ret = VIRTIO_CRYPTO_ERR;
                        goto error_exit;
@@ -1079,14 +1095,15 @@ prepare_sym_chain_op(struct vhost_crypto *vcrypto, struct rte_crypto_op *op,
                /** create a wb_data for digest */
                ewb->next = prepare_write_back_data(vc_req, &desc, &ewb2,
                                digest_addr, 0, chain->para.hash_result_len,
-                               nb_descs);
+                               nb_descs, vq_size);
                if (unlikely(ewb->next == NULL)) {
                        ret = VIRTIO_CRYPTO_ERR;
                        goto error_exit;
                }
 
                if (unlikely(copy_data(digest_addr, vc_req, &digest_desc,
-                               chain->para.hash_result_len, nb_descs)) < 0) {
+                               chain->para.hash_result_len,
+                               nb_descs, vq_size)) < 0) {
                        ret = VIRTIO_CRYPTO_BADMSG;
                        goto error_exit;
                }
@@ -1181,7 +1198,7 @@ vhost_crypto_process_one_req(struct vhost_crypto *vcrypto,
                case RTE_VHOST_CRYPTO_ZERO_COPY_DISABLE:
                        req = &tmp_req;
                        if (unlikely(copy_data(req, vc_req, &desc, sizeof(*req),
-                                       &nb_descs) < 0)) {
+                                       &nb_descs, vq->size) < 0)) {
                                err = VIRTIO_CRYPTO_BADMSG;
                                VC_LOG_ERR("Invalid descriptor");
                                goto error_exit;
@@ -1194,7 +1211,7 @@ vhost_crypto_process_one_req(struct vhost_crypto *vcrypto,
                }
        } else {
                if (unlikely(move_desc(vc_req->head, &desc,
-                               sizeof(*req), &nb_descs) < 0)) {
+                               sizeof(*req), &nb_descs, vq->size) < 0)) {
                        VC_LOG_ERR("Incorrect descriptor");
                        goto error_exit;
                }
@@ -1236,12 +1253,12 @@ vhost_crypto_process_one_req(struct vhost_crypto *vcrypto,
                case VIRTIO_CRYPTO_SYM_OP_CIPHER:
                        err = prepare_sym_cipher_op(vcrypto, op, vc_req,
                                        &req->u.sym_req.u.cipher, desc,
-                                       &nb_descs);
+                                       &nb_descs, vq->size);
                        break;
                case VIRTIO_CRYPTO_SYM_OP_ALGORITHM_CHAINING:
                        err = prepare_sym_chain_op(vcrypto, op, vc_req,
                                        &req->u.sym_req.u.chain, desc,
-                                       &nb_descs);
+                                       &nb_descs, vq->size);
                        break;
                }
                if (unlikely(err != 0)) {
@@ -1259,7 +1276,7 @@ vhost_crypto_process_one_req(struct vhost_crypto *vcrypto,
 
 error_exit:
 
-       inhdr = reach_inhdr(vc_req, desc, &nb_descs);
+       inhdr = reach_inhdr(vc_req, desc, &nb_descs, vq->size);
        if (likely(inhdr != NULL))
                inhdr->status = (uint8_t)err;