vhost: introduce safe API for GPA translation

This new rte_vhost_va_from_guest_pa API takes an extra len
parameter, used to specify the size of the range to be mapped.
Effective mapped range is returned via len parameter.

This issue has been assigned CVE-2018-1059.

Reported-by: Yongji Xie <xieyongji@baidu.com>
Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
This commit is contained in:
Maxime Coquelin 2018-01-23 14:37:50 +01:00
parent 070aceda33
commit 41333fba5b
3 changed files with 44 additions and 2 deletions

View File

@ -149,6 +149,46 @@ rte_vhost_gpa_to_vva(struct rte_vhost_memory *mem, uint64_t gpa)
return 0;
}
/**
* Convert guest physical address to host virtual address safely
*
* This variant of rte_vhost_gpa_to_vva() takes care all the
* requested length is mapped and contiguous in process address
* space.
*
* @param mem
* the guest memory regions
* @param gpa
* the guest physical address for querying
* @param len
* the size of the requested area to map, updated with actual size mapped
* @return
* the host virtual address on success, 0 on failure
*/
static __rte_always_inline uint64_t
rte_vhost_va_from_guest_pa(struct rte_vhost_memory *mem,
uint64_t gpa, uint64_t *len)
{
struct rte_vhost_mem_region *r;
uint32_t i;
for (i = 0; i < mem->nregions; i++) {
r = &mem->regions[i];
if (gpa >= r->guest_phys_addr &&
gpa < r->guest_phys_addr + r->size) {
if (unlikely(*len > r->guest_phys_addr + r->size - gpa))
*len = r->guest_phys_addr + r->size - gpa;
return gpa - r->guest_phys_addr +
r->host_user_addr;
}
}
*len = 0;
return 0;
}
#define RTE_VHOST_NEED_LOG(features) ((features) & (1ULL << VHOST_F_LOG_ALL))
/**

View File

@ -61,6 +61,8 @@ DPDK_18.02 {
} DPDK_17.08;
EXPERIMENTAL {
global:
rte_vdpa_register_device;
rte_vdpa_unregister_device;
rte_vdpa_find_device_id;
@ -79,5 +81,5 @@ EXPERIMENTAL {
rte_vhost_crypto_fetch_requests;
rte_vhost_crypto_finalize_requests;
rte_vhost_crypto_set_zero_copy;
rte_vhost_va_from_guest_pa;
} DPDK_18.02;

View File

@ -446,7 +446,7 @@ vhost_iova_to_vva(struct virtio_net *dev, struct vhost_virtqueue *vq,
uint64_t iova, uint64_t *len, uint8_t perm)
{
if (!(dev->features & (1ULL << VIRTIO_F_IOMMU_PLATFORM)))
return rte_vhost_gpa_to_vva(dev->mem, iova);
return rte_vhost_va_from_guest_pa(dev->mem, iova, len);
return __vhost_iova_to_vva(dev, vq, iova, len, perm);
}