kvm/arm64 fixes for 5.10, take

- Don't leak page tables on PTE update
 - Correctly invalidate TLBs on table to block transition
 - Only update permissions if the fault level matches the
   expected mapping size
 -----BEGIN PGP SIGNATURE-----
 
 iQJDBAABCgAtFiEEn9UcU+C1Yxj9lZw9I9DQutE9ekMFAl/KerUPHG1hekBrZXJu
 ZWwub3JnAAoJECPQ0LrRPXpD814P/1tEItvIx2rfWXT7zD/pfOImqGeDLKY7JUEx
 tcOVfKDvFqeT/aiArsp7VlRR5FV8Y97VAzSHpyVyT7zJYyD6NkRUXjD/tzMK0pmb
 jQoo2EKAWokl3lAETKsTh44ZweOM5kYvnM0IQf+lpZq58SMMWwB/62R6vZjJLsTT
 BmPiINYOf+zhAXbjqGmh9buwvzn00hHq6kzz96tWhyBR+ZluVaYByHdbIdcCzB93
 kX13ndVart8H6zrghhJy+ZwXd5WYMJPXAg/eGZSBSrIZDC/EzxAPBAQczYelqj3v
 g3cZ+HQhPnePgmEQ5VYB2gQIWO/kjwgumS0TfzYUBDKTXWwxMdxAwwY6vR8CVUY7
 HVr06Moyx+SVc6oY2iePYx6BDCg4I6sOWGux01usy9izsbUUqOggWGBnEWViSojX
 bn8jriYemkC4hZ6CKgn0K4Y9J9M6LjxBgwxdHmoPGNLBI6B1sdKmA8gCn6W+oLew
 nr/0yquuijWrASXrQjK56nKBP44jX+sSlsNzjKN/cd8UyCu44649239GhEgSXGgj
 EIf4aqhv1HgiF0ceXwQ+jFu8bp+KCR8YNt27cGf/HNz+xAaBFk0M2DUX/N9DrHko
 e1gK8MxOX26vvuCjCQo05rRx9nO4FXUZEMewSGLLxqdj2aPG6miI8/Gq929WeuSX
 zNnWPS2M
 =+7gU
 -----END PGP SIGNATURE-----

Merge tag 'kvmarm-fixes-5.10-5' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

kvm/arm64 fixes for 5.10, take 

- Don't leak page tables on PTE update
- Correctly invalidate TLBs on table to block transition
- Only update permissions if the fault level matches the
  expected mapping size
This commit is contained in:
Paolo Bonzini 2020-12-10 11:34:24 -05:00
commit 83bbb8ffb4
4 changed files with 31 additions and 3 deletions
arch/arm64

View File

@ -104,6 +104,7 @@
/* Shared ISS fault status code(IFSC/DFSC) for Data/Instruction aborts */
#define ESR_ELx_FSC (0x3F)
#define ESR_ELx_FSC_TYPE (0x3C)
#define ESR_ELx_FSC_LEVEL (0x03)
#define ESR_ELx_FSC_EXTABT (0x10)
#define ESR_ELx_FSC_SERROR (0x11)
#define ESR_ELx_FSC_ACCESS (0x08)

View File

@ -350,6 +350,11 @@ static __always_inline u8 kvm_vcpu_trap_get_fault_type(const struct kvm_vcpu *vc
return kvm_vcpu_get_esr(vcpu) & ESR_ELx_FSC_TYPE;
}
static __always_inline u8 kvm_vcpu_trap_get_fault_level(const struct kvm_vcpu *vcpu)
{
return kvm_vcpu_get_esr(vcpu) & ESR_ELx_FSC_LEVEL;
}
static __always_inline bool kvm_vcpu_abt_issea(const struct kvm_vcpu *vcpu)
{
switch (kvm_vcpu_trap_get_fault(vcpu)) {

View File

@ -470,6 +470,15 @@ static bool stage2_map_walker_try_leaf(u64 addr, u64 end, u32 level,
if (!kvm_block_mapping_supported(addr, end, phys, level))
return false;
/*
* If the PTE was already valid, drop the refcount on the table
* early, as it will be bumped-up again in stage2_map_walk_leaf().
* This ensures that the refcount stays constant across a valid to
* valid PTE update.
*/
if (kvm_pte_valid(*ptep))
put_page(virt_to_page(ptep));
if (kvm_set_valid_leaf_pte(ptep, phys, data->attr, level))
goto out;
@ -493,7 +502,13 @@ static int stage2_map_walk_table_pre(u64 addr, u64 end, u32 level,
return 0;
kvm_set_invalid_pte(ptep);
kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, data->mmu, addr, 0);
/*
* Invalidate the whole stage-2, as we may have numerous leaf
* entries below us which would otherwise need invalidating
* individually.
*/
kvm_call_hyp(__kvm_tlb_flush_vmid, data->mmu);
data->anchor = ptep;
return 0;
}

View File

@ -754,10 +754,12 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
gfn_t gfn;
kvm_pfn_t pfn;
bool logging_active = memslot_is_logging(memslot);
unsigned long vma_pagesize;
unsigned long fault_level = kvm_vcpu_trap_get_fault_level(vcpu);
unsigned long vma_pagesize, fault_granule;
enum kvm_pgtable_prot prot = KVM_PGTABLE_PROT_R;
struct kvm_pgtable *pgt;
fault_granule = 1UL << ARM64_HW_PGTABLE_LEVEL_SHIFT(fault_level);
write_fault = kvm_is_write_fault(vcpu);
exec_fault = kvm_vcpu_trap_is_exec_fault(vcpu);
VM_BUG_ON(write_fault && exec_fault);
@ -896,7 +898,12 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
else if (cpus_have_const_cap(ARM64_HAS_CACHE_DIC))
prot |= KVM_PGTABLE_PROT_X;
if (fault_status == FSC_PERM && !(logging_active && writable)) {
/*
* Under the premise of getting a FSC_PERM fault, we just need to relax
* permissions only if vma_pagesize equals fault_granule. Otherwise,
* kvm_pgtable_stage2_map() should be called to change block size.
*/
if (fault_status == FSC_PERM && vma_pagesize == fault_granule) {
ret = kvm_pgtable_stage2_relax_perms(pgt, fault_ipa, prot);
} else {
ret = kvm_pgtable_stage2_map(pgt, fault_ipa, vma_pagesize,