Seen during KPTI initialization:
CFI failure at create_kpti_ng_temp_pgd+0x124/0xce8 (target:
kpti_ng_pgd_alloc+0x0/0x14; expected type: 0xd61b88b6)
The call site is alloc_init_pud() at arch/arm64/mm/mmu.c:
pud_phys = pgtable_alloc(TABLE_PUD);
alloc_init_pud() has the prototype:
static void alloc_init_pud(p4d_t *p4dp, unsigned long addr, unsigned long end,
phys_addr_t phys, pgprot_t prot,
phys_addr_t (*pgtable_alloc)(enum pgtable_type),
int flags)
where the pgtable_alloc() prototype is declared.
The target (kpti_ng_pgd_alloc) is used in arch/arm64/kernel/cpufeature.c:
create_kpti_ng_temp_pgd(kpti_ng_temp_pgd, __pa(alloc), KPTI_NG_TEMP_VA,
PAGE_SIZE, PAGE_KERNEL, kpti_ng_pgd_alloc, 0);
which is an alias for __create_pgd_mapping_locked() with prototype:
extern __alias(__create_pgd_mapping_locked)
void create_kpti_ng_temp_pgd(pgd_t *pgdir, phys_addr_t phys,
unsigned long virt,
phys_addr_t size, pgprot_t prot,
phys_addr_t (*pgtable_alloc)(enum pgtable_type),
int flags);
__create_pgd_mapping_locked() passes the function pointer down:
__create_pgd_mapping_locked() -> alloc_init_p4d() -> alloc_init_pud()
But the target function (kpti_ng_pgd_alloc) has the wrong signature:
static phys_addr_t __init kpti_ng_pgd_alloc(int shift);
The "int" should be "enum pgtable_type".
To make "enum pgtable_type" available to cpufeature.c, move
enum pgtable_type definition from arch/arm64/mm/mmu.c to
arch/arm64/include/asm/mmu.h.
Adjust kpti_ng_pgd_alloc to use "enum pgtable_type" instead of "int".
The function behavior remains identical (parameter is unused).
Fixes: 47546a1912fc ("arm64: mm: install KPTI nG mappings with MMU enabled")
Signed-off-by: Kees Cook <k...@kernel.org>
---
Cc: Ard Biesheuvel <a...@kernel.org>
Cc: Catalin Marinas <catalin.mari...@arm.com>
Cc: Will Deacon <w...@kernel.org>
Cc: Oliver Upton <oliver.up...@linux.dev>
Cc: Anshuman Khandual <anshuman.khand...@arm.com>
Cc: Yue Haibing <yuehaib...@huawei.com>
Cc: Mark Rutland <mark.rutl...@arm.com>
Cc: Marc Zyngier <m...@kernel.org>
Cc: Mark Brown <broo...@kernel.org>
Cc: <linux-arm-ker...@lists.infradead.org>
---
arch/arm64/include/asm/mmu.h | 7 +++++++
arch/arm64/kernel/cpufeature.c | 5 +++--
arch/arm64/mm/mmu.c | 7 -------
3 files changed, 10 insertions(+), 9 deletions(-)
diff --git a/arch/arm64/include/asm/mmu.h b/arch/arm64/include/asm/mmu.h
index 6e8aa8e72601..49f1a810df16 100644
--- a/arch/arm64/include/asm/mmu.h
+++ b/arch/arm64/include/asm/mmu.h
@@ -17,6 +17,13 @@
#include <linux/refcount.h>
#include <asm/cpufeature.h>
+enum pgtable_type {
+ TABLE_PTE,
+ TABLE_PMD,
+ TABLE_PUD,
+ TABLE_P4D,
+};
+
typedef struct {
atomic64_t id;
#ifdef CONFIG_COMPAT
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 9ad065f15f1d..e49d142a281f 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -84,6 +84,7 @@
#include <asm/hwcap.h>
#include <asm/insn.h>
#include <asm/kvm_host.h>
+#include <asm/mmu.h>
#include <asm/mmu_context.h>
#include <asm/mte.h>
#include <asm/hypervisor.h>
@@ -1945,11 +1946,11 @@ static bool has_pmuv3(const struct
arm64_cpu_capabilities *entry, int scope)
extern
void create_kpti_ng_temp_pgd(pgd_t *pgdir, phys_addr_t phys, unsigned long
virt,
phys_addr_t size, pgprot_t prot,
- phys_addr_t (*pgtable_alloc)(int), int flags);
+ phys_addr_t (*pgtable_alloc)(enum pgtable_type),
int flags);
static phys_addr_t __initdata kpti_ng_temp_alloc;
-static phys_addr_t __init kpti_ng_pgd_alloc(int shift)
+static phys_addr_t __init kpti_ng_pgd_alloc(enum pgtable_type type)
{
kpti_ng_temp_alloc -= PAGE_SIZE;
return kpti_ng_temp_alloc;
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 34e5d78af076..183801520740 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -47,13 +47,6 @@
#define NO_CONT_MAPPINGS BIT(1)
#define NO_EXEC_MAPPINGS BIT(2) /* assumes FEAT_HPDS is not used */
-enum pgtable_type {
- TABLE_PTE,
- TABLE_PMD,
- TABLE_PUD,
- TABLE_P4D,
-};
-
u64 kimage_voffset __ro_after_init;
EXPORT_SYMBOL(kimage_voffset);
--
2.34.1
