hv:bugfix in write protect page hypercall

This patch fixes potential hypervisor crash when
 calling hcall_write_protect_page() with a crafted
 GPA in 'struct wp_data' instance, e.g. an invalid
 GPA that is not in the scope of the target VM's
 EPT address space.

 To check the validity for this GPA  before updating
 the 'write protect' page.

Tracked-On: #4240
Signed-off-by: Yonghua Huang <yonghua.huang@intel.com>
Reviewed-by: Fei Li <fei1.li@intel.com>
This commit is contained in:
Yonghua Huang 2019-12-12 15:34:56 +08:00 committed by wenlingz
parent 1636ac0416
commit 05682b2bad

View File

@ -714,30 +714,34 @@ static int32_t write_protect_page(struct acrn_vm *vm,const struct wp_data *wp)
uint64_t hpa, base_paddr;
uint64_t prot_set;
uint64_t prot_clr;
int32_t ret;
int32_t ret = -EINVAL;
hpa = gpa2hpa(vm, wp->gpa);
if (hpa == INVALID_HPA) {
pr_err("%s,vm[%hu] gpa 0x%lx,GPA is unmapping.",
if ((!mem_aligned_check(wp->gpa, PAGE_SIZE)) ||
(!ept_is_mr_valid(vm, wp->gpa, PAGE_SIZE))) {
pr_err("%s,vm[%hu] gpa 0x%lx,GPA is invalid or not page size aligned.",
__func__, vm->vm_id, wp->gpa);
ret = -EINVAL;
} else {
dev_dbg(ACRN_DBG_HYCALL, "[vm%d] gpa=0x%x hpa=0x%x",
hpa = gpa2hpa(vm, wp->gpa);
if (hpa == INVALID_HPA) {
pr_err("%s,vm[%hu] gpa 0x%lx,GPA is unmapping.",
__func__, vm->vm_id, wp->gpa);
} else {
dev_dbg(ACRN_DBG_HYCALL, "[vm%d] gpa=0x%x hpa=0x%x",
vm->vm_id, wp->gpa, hpa);
base_paddr = hva2hpa((void *)(get_hv_image_base()));
if (((hpa <= base_paddr) && ((hpa + PAGE_SIZE) > base_paddr)) ||
base_paddr = hva2hpa((void *)(get_hv_image_base()));
if (((hpa <= base_paddr) && ((hpa + PAGE_SIZE) > base_paddr)) ||
((hpa >= base_paddr) &&
(hpa < (base_paddr + CONFIG_HV_RAM_SIZE)))) {
pr_err("%s: overlap the HV memory region.", __func__);
ret = -EINVAL;
} else {
prot_set = (wp->set != 0U) ? 0UL : EPT_WR;
prot_clr = (wp->set != 0U) ? EPT_WR : 0UL;
pr_err("%s: overlap the HV memory region.", __func__);
} else {
prot_set = (wp->set != 0U) ? 0UL : EPT_WR;
prot_clr = (wp->set != 0U) ? EPT_WR : 0UL;
ept_modify_mr(vm, (uint64_t *)vm->arch_vm.nworld_eptp,
wp->gpa, PAGE_SIZE, prot_set, prot_clr);
ret = 0;
ept_modify_mr(vm, (uint64_t *)vm->arch_vm.nworld_eptp,
wp->gpa, PAGE_SIZE, prot_set, prot_clr);
ret = 0;
}
}
}