@@ -97,15 +97,24 @@ int __init efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md)
return 0;
}
+struct set_perm_data {
+ const efi_memory_desc_t *md;
+ bool has_bti;
+};
+
static int __init set_permissions(pte_t *ptep, unsigned long addr, void *data)
{
- efi_memory_desc_t *md = data;
+ struct set_perm_data *spd = data;
+ const efi_memory_desc_t *md = spd->md;
pte_t pte = READ_ONCE(*ptep);
if (md->attribute & EFI_MEMORY_RO)
pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
if (md->attribute & EFI_MEMORY_XP)
pte = set_pte_bit(pte, __pgprot(PTE_PXN));
+ else if (IS_ENABLED(CONFIG_ARM64_BTI_KERNEL) &&
+ system_supports_bti() && spd->has_bti)
+ pte = set_pte_bit(pte, __pgprot(PTE_GP));
set_pte(ptep, pte);
return 0;
}
@@ -114,6 +123,8 @@ int __init efi_set_mapping_permissions(struct mm_struct *mm,
efi_memory_desc_t *md,
bool has_bti)
{
+ struct set_perm_data data = { md, has_bti };
+
BUG_ON(md->type != EFI_RUNTIME_SERVICES_CODE &&
md->type != EFI_RUNTIME_SERVICES_DATA);
@@ -129,7 +140,7 @@ int __init efi_set_mapping_permissions(struct mm_struct *mm,
*/
return apply_to_page_range(mm, md->virt_addr,
md->num_pages << EFI_PAGE_SHIFT,
- set_permissions, md);
+ set_permissions, &data);
}
/*
UEFI v2.10 extends the EFI memory attributes table with a flag that indicates whether or not all RuntimeServicesCode regions were constructed with BTI landing pads, permitting the OS to map these regions with BTI restrictions enabled. So let's take this into account on arm64. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> --- arch/arm64/kernel/efi.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-)