aboutsummaryrefslogtreecommitdiff
path: root/arch/arm64
diff options
context:
space:
mode:
authorLinus Torvalds2023-02-23 14:41:48 -0800
committerLinus Torvalds2023-02-23 14:41:48 -0800
commit06e1a81c4806d0b7f75f9d742ebf410718244e03 (patch)
tree05c97c56f6c755608c01cc0160ba33c4db88f1de /arch/arm64
parentf2b98d0af217f64b96bc549457018117ba6b7509 (diff)
parente1d447157f232c650e6f32c9fb89ff3d0207c69a (diff)
Merge tag 'efi-next-for-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi
Pull EFI updates from Ard Biesheuvel: "A healthy mix of EFI contributions this time: - Performance tweaks for efifb earlycon (Andy) - Preparatory refactoring and cleanup work in the efivar layer, which is needed to accommodate the Snapdragon arm64 laptops that expose their EFI variable store via a TEE secure world API (Johan) - Enhancements to the EFI memory map handling so that Xen dom0 can safely access EFI configuration tables (Demi Marie) - Wire up the newly introduced IBT/BTI flag in the EFI memory attributes table, so that firmware that is generated with ENDBR/BTI landing pads will be mapped with enforcement enabled - Clean up how we check and print the EFI revision exposed by the firmware - Incorporate EFI memory attributes protocol definition and wire it up in the EFI zboot code (Evgeniy) This ensures that these images can execute under new and stricter rules regarding the default memory permissions for EFI page allocations (More work is in progress here) - CPER header cleanup (Dan Williams) - Use a raw spinlock to protect the EFI runtime services stack on arm64 to ensure the correct semantics under -rt (Pierre) - EFI framebuffer quirk for Lenovo Ideapad (Darrell)" * tag 'efi-next-for-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi: (24 commits) firmware/efi sysfb_efi: Add quirk for Lenovo IdeaPad Duet 3 arm64: efi: Make efi_rt_lock a raw_spinlock efi: Add mixed-mode thunk recipe for GetMemoryAttributes efi: x86: Wire up IBT annotation in memory attributes table efi: arm64: Wire up BTI annotation in memory attributes table efi: Discover BTI support in runtime services regions efi/cper, cxl: Remove cxl_err.h efi: Use standard format for printing the EFI revision efi: Drop minimum EFI version check at boot efi: zboot: Use EFI protocol to remap code/data with the right attributes efi/libstub: Add memory attribute protocol definitions efi: efivars: prevent double registration efi: verify that variable services are supported efivarfs: always register filesystem efi: efivars: add efivars printk prefix efi: Warn if trying to reserve memory under Xen efi: Actually enable the ESRT under Xen efi: Apply allowlist to EFI configuration tables when running under Xen efi: xen: Implement memory descriptor lookup based on hypercall efi: memmap: Disregard bogus entries instead of returning them ...
Diffstat (limited to 'arch/arm64')
-rw-r--r--arch/arm64/include/asm/efi.h9
-rw-r--r--arch/arm64/kernel/efi.c20
-rw-r--r--arch/arm64/kernel/traps.c6
3 files changed, 27 insertions, 8 deletions
diff --git a/arch/arm64/include/asm/efi.h b/arch/arm64/include/asm/efi.h
index acaa39f6381a..f86b157a5da3 100644
--- a/arch/arm64/include/asm/efi.h
+++ b/arch/arm64/include/asm/efi.h
@@ -27,13 +27,14 @@ bool efi_runtime_fixup_exception(struct pt_regs *regs, const char *msg)
#endif
int efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md);
-int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md);
+int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md,
+ bool has_bti);
#define arch_efi_call_virt_setup() \
({ \
efi_virtmap_load(); \
__efi_fpsimd_begin(); \
- spin_lock(&efi_rt_lock); \
+ raw_spin_lock(&efi_rt_lock); \
})
#undef arch_efi_call_virt
@@ -42,12 +43,12 @@ int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md);
#define arch_efi_call_virt_teardown() \
({ \
- spin_unlock(&efi_rt_lock); \
+ raw_spin_unlock(&efi_rt_lock); \
__efi_fpsimd_end(); \
efi_virtmap_unload(); \
})
-extern spinlock_t efi_rt_lock;
+extern raw_spinlock_t efi_rt_lock;
extern u64 *efi_rt_stack_top;
efi_status_t __efi_rt_asm_wrapper(void *, const char *, ...);
diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c
index b273900f4566..baab8dd3ead3 100644
--- a/arch/arm64/kernel/efi.c
+++ b/arch/arm64/kernel/efi.c
@@ -97,22 +97,34 @@ 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;
}
int __init efi_set_mapping_permissions(struct mm_struct *mm,
- efi_memory_desc_t *md)
+ 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);
@@ -128,7 +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);
}
/*
@@ -146,7 +158,7 @@ asmlinkage efi_status_t efi_handle_corrupted_x18(efi_status_t s, const char *f)
return s;
}
-DEFINE_SPINLOCK(efi_rt_lock);
+DEFINE_RAW_SPINLOCK(efi_rt_lock);
asmlinkage u64 *efi_rt_stack_top __ro_after_init;
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index a6dd3e90755c..901dfd9bf04c 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -18,6 +18,7 @@
#include <linux/module.h>
#include <linux/kexec.h>
#include <linux/delay.h>
+#include <linux/efi.h>
#include <linux/init.h>
#include <linux/sched/signal.h>
#include <linux/sched/debug.h>
@@ -34,6 +35,7 @@
#include <asm/cpufeature.h>
#include <asm/daifflags.h>
#include <asm/debug-monitors.h>
+#include <asm/efi.h>
#include <asm/esr.h>
#include <asm/exception.h>
#include <asm/extable.h>
@@ -491,6 +493,10 @@ void do_el0_bti(struct pt_regs *regs)
void do_el1_bti(struct pt_regs *regs, unsigned long esr)
{
+ if (efi_runtime_fixup_exception(regs, "BTI violation")) {
+ regs->pstate &= ~PSR_BTYPE_MASK;
+ return;
+ }
die("Oops - BTI", regs, esr);
}