First batch of EFI fixes for v6.1

- A pair of fixes for the EFI variable store refactor that landed in
   v6.0
 - A couple of fixes for issue that were introduced during the merge
   window
 - Back out some changes related to EFI zboot signing - we'll add a
   better solution for this during the next cycle
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Merge tag 'efi-fixes-for-v6.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi

Pull EFI fixes from Ard Biesheuvel:

 - fixes for the EFI variable store refactor that landed in v6.0

 - fixes for issues that were introduced during the merge window

 - back out some changes related to EFI zboot signing - we'll add a
   better solution for this during the next cycle

* tag 'efi-fixes-for-v6.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
  efi: runtime: Don't assume virtual mappings are missing if VA == PA == 0
  efi: libstub: Fix incorrect payload size in zboot header
  efi: libstub: Give efi_main() asmlinkage qualification
  efi: efivars: Fix variable writes without query_variable_store()
  efi: ssdt: Don't free memory if ACPI table was loaded successfully
  efi: libstub: Remove zboot signing from build options

drivers/firmware/efi/Kconfig

@@ -124,28 +124,6 @@ config EFI_ZBOOT
 	  is supported by the encapsulated image. (The compression algorithm
 	  used is described in the zboot image header)
 
-config EFI_ZBOOT_SIGNED
-	def_bool y
-	depends on EFI_ZBOOT_SIGNING_CERT != ""
-	depends on EFI_ZBOOT_SIGNING_KEY != ""
-
-config EFI_ZBOOT_SIGNING
-	bool "Sign the EFI decompressor for UEFI secure boot"
-	depends on EFI_ZBOOT
-	help
-	  Use the 'sbsign' command line tool (which must exist on the host
-	  path) to sign both the EFI decompressor PE/COFF image, as well as the
-	  encapsulated PE/COFF image, which is subsequently compressed and
-	  wrapped by the former image.
-
-config EFI_ZBOOT_SIGNING_CERT
-	string "Certificate to use for signing the compressed EFI boot image"
-	depends on EFI_ZBOOT_SIGNING
-
-config EFI_ZBOOT_SIGNING_KEY
-	string "Private key to use for signing the compressed EFI boot image"
-	depends on EFI_ZBOOT_SIGNING
-
 config EFI_ARMSTUB_DTB_LOADER
 	bool "Enable the DTB loader"
 	depends on EFI_GENERIC_STUB && !RISCV && !LOONGARCH

drivers/firmware/efi/arm-runtime.c

@@ -63,7 +63,7 @@ static bool __init efi_virtmap_init(void)
 
 		if (!(md->attribute & EFI_MEMORY_RUNTIME))
 			continue;
-		if (md->virt_addr == 0)
+		if (md->virt_addr == U64_MAX)
 			return false;
 
 		ret = efi_create_mapping(&efi_mm, md);

drivers/firmware/efi/efi.c

@@ -271,6 +271,8 @@ static __init int efivar_ssdt_load(void)
 			acpi_status ret = acpi_load_table(data, NULL);
 			if (ret)
 				pr_err("failed to load table: %u\n", ret);
+			else
+				continue;
 		} else {
 			pr_err("failed to get var data: 0x%lx\n", status);
 		}

drivers/firmware/efi/libstub/Makefile.zboot

@@ -20,22 +20,11 @@ zboot-size-len-y			:= 4
 zboot-method-$(CONFIG_KERNEL_GZIP)	:= gzip
 zboot-size-len-$(CONFIG_KERNEL_GZIP)	:= 0
 
-quiet_cmd_sbsign = SBSIGN  $@
+$(obj)/vmlinuz: $(obj)/$(EFI_ZBOOT_PAYLOAD) FORCE
-      cmd_sbsign = sbsign --out $@ $< \
-		   --key $(CONFIG_EFI_ZBOOT_SIGNING_KEY) \
-		   --cert $(CONFIG_EFI_ZBOOT_SIGNING_CERT)
-
-$(obj)/$(EFI_ZBOOT_PAYLOAD).signed: $(obj)/$(EFI_ZBOOT_PAYLOAD) FORCE
-	$(call if_changed,sbsign)
-
-ZBOOT_PAYLOAD-y				 := $(EFI_ZBOOT_PAYLOAD)
-ZBOOT_PAYLOAD-$(CONFIG_EFI_ZBOOT_SIGNED) := $(EFI_ZBOOT_PAYLOAD).signed
-
-$(obj)/vmlinuz: $(obj)/$(ZBOOT_PAYLOAD-y) FORCE
 	$(call if_changed,$(zboot-method-y))
 
 OBJCOPYFLAGS_vmlinuz.o := -I binary -O $(EFI_ZBOOT_BFD_TARGET) \
-			 --rename-section .data=.gzdata,load,alloc,readonly,contents
+			  --rename-section .data=.gzdata,load,alloc,readonly,contents
 $(obj)/vmlinuz.o: $(obj)/vmlinuz FORCE
 	$(call if_changed,objcopy)
 
@@ -53,18 +42,8 @@ LDFLAGS_vmlinuz.efi.elf := -T $(srctree)/drivers/firmware/efi/libstub/zboot.lds
 $(obj)/vmlinuz.efi.elf: $(obj)/vmlinuz.o $(ZBOOT_DEPS) FORCE
 	$(call if_changed,ld)
 
-ZBOOT_EFI-y				:= vmlinuz.efi
+OBJCOPYFLAGS_vmlinuz.efi := -O binary
-ZBOOT_EFI-$(CONFIG_EFI_ZBOOT_SIGNED)	:= vmlinuz.efi.unsigned
+$(obj)/vmlinuz.efi: $(obj)/vmlinuz.efi.elf FORCE
-
-OBJCOPYFLAGS_$(ZBOOT_EFI-y) := -O binary
-$(obj)/$(ZBOOT_EFI-y): $(obj)/vmlinuz.efi.elf FORCE
 	$(call if_changed,objcopy)
 
 targets += zboot-header.o vmlinuz vmlinuz.o vmlinuz.efi.elf vmlinuz.efi
-
-ifneq ($(CONFIG_EFI_ZBOOT_SIGNED),)
-$(obj)/vmlinuz.efi: $(obj)/vmlinuz.efi.unsigned FORCE
-	$(call if_changed,sbsign)
-endif
-
-targets += $(EFI_ZBOOT_PAYLOAD).signed vmlinuz.efi.unsigned

drivers/firmware/efi/libstub/fdt.c

@@ -313,16 +313,16 @@ efi_status_t allocate_new_fdt_and_exit_boot(void *handle,
 
 			/*
 			 * Set the virtual address field of all
-			 * EFI_MEMORY_RUNTIME entries to 0. This will signal
+			 * EFI_MEMORY_RUNTIME entries to U64_MAX. This will
-			 * the incoming kernel that no virtual translation has
+			 * signal the incoming kernel that no virtual
-			 * been installed.
+			 * translation has been installed.
 			 */
 			for (l = 0; l < priv.boot_memmap->map_size;
 			     l += priv.boot_memmap->desc_size) {
 				p = (void *)priv.boot_memmap->map + l;
 
 				if (p->attribute & EFI_MEMORY_RUNTIME)
-					p->virt_addr = 0;
+					p->virt_addr = U64_MAX;
 			}
 		}
 		return EFI_SUCCESS;

drivers/firmware/efi/libstub/x86-stub.c

@@ -765,9 +765,9 @@ static efi_status_t exit_boot(struct boot_params *boot_params, void *handle)
  * relocated by efi_relocate_kernel.
  * On failure, we exit to the firmware via efi_exit instead of returning.
  */
-unsigned long efi_main(efi_handle_t handle,
+asmlinkage unsigned long efi_main(efi_handle_t handle,
-			     efi_system_table_t *sys_table_arg,
+				  efi_system_table_t *sys_table_arg,
-			     struct boot_params *boot_params)
+				  struct boot_params *boot_params)
 {
 	unsigned long bzimage_addr = (unsigned long)startup_32;
 	unsigned long buffer_start, buffer_end;

drivers/firmware/efi/libstub/zboot.lds

@@ -38,7 +38,8 @@ SECTIONS
 	}
 }
 
-PROVIDE(__efistub__gzdata_size = ABSOLUTE(. - __efistub__gzdata_start));
+PROVIDE(__efistub__gzdata_size =
+		ABSOLUTE(__efistub__gzdata_end - __efistub__gzdata_start));
 
 PROVIDE(__data_rawsize = ABSOLUTE(_edata - _etext));
 PROVIDE(__data_size = ABSOLUTE(_end - _etext));

drivers/firmware/efi/riscv-runtime.c

@@ -41,7 +41,7 @@ static bool __init efi_virtmap_init(void)
 
 		if (!(md->attribute & EFI_MEMORY_RUNTIME))
 			continue;
-		if (md->virt_addr == 0)
+		if (md->virt_addr == U64_MAX)
 			return false;
 
 		ret = efi_create_mapping(&efi_mm, md);

drivers/firmware/efi/vars.c

@@ -7,6 +7,7 @@
  */
 
 #include <linux/types.h>
+#include <linux/sizes.h>
 #include <linux/errno.h>
 #include <linux/init.h>
 #include <linux/module.h>
@@ -20,19 +21,19 @@ static struct efivars *__efivars;
 
 static DEFINE_SEMAPHORE(efivars_lock);
 
-efi_status_t check_var_size(u32 attributes, unsigned long size)
+static efi_status_t check_var_size(u32 attributes, unsigned long size)
 {
 	const struct efivar_operations *fops;
 
 	fops = __efivars->ops;
 
 	if (!fops->query_variable_store)
-		return EFI_UNSUPPORTED;
+		return (size <= SZ_64K) ? EFI_SUCCESS : EFI_OUT_OF_RESOURCES;
 
 	return fops->query_variable_store(attributes, size, false);
 }
-EXPORT_SYMBOL_NS_GPL(check_var_size, EFIVAR);
 
+static
 efi_status_t check_var_size_nonblocking(u32 attributes, unsigned long size)
 {
 	const struct efivar_operations *fops;
@@ -40,11 +41,10 @@ efi_status_t check_var_size_nonblocking(u32 attributes, unsigned long size)
 	fops = __efivars->ops;
 
 	if (!fops->query_variable_store)
-		return EFI_UNSUPPORTED;
+		return (size <= SZ_64K) ? EFI_SUCCESS : EFI_OUT_OF_RESOURCES;
 
 	return fops->query_variable_store(attributes, size, true);
 }
-EXPORT_SYMBOL_NS_GPL(check_var_size_nonblocking, EFIVAR);
 
 /**
  * efivars_kobject - get the kobject for the registered efivars

fs/efivarfs/vars.c

@@ -651,22 +651,6 @@ int efivar_entry_set_get_size(struct efivar_entry *entry, u32 attributes,
 	if (err)
 		return err;
 
-	/*
-	 * Ensure that the available space hasn't shrunk below the safe level
-	 */
-	status = check_var_size(attributes, *size + ucs2_strsize(name, 1024));
-	if (status != EFI_SUCCESS) {
-		if (status != EFI_UNSUPPORTED) {
-			err = efi_status_to_err(status);
-			goto out;
-		}
-
-		if (*size > 65536) {
-			err = -ENOSPC;
-			goto out;
-		}
-	}
-
 	status = efivar_set_variable_locked(name, vendor, attributes, *size,
 					    data, false);
 	if (status != EFI_SUCCESS) {

include/linux/efi.h

@@ -1085,9 +1085,6 @@ efi_status_t efivar_set_variable_locked(efi_char16_t *name, efi_guid_t *vendor,
 efi_status_t efivar_set_variable(efi_char16_t *name, efi_guid_t *vendor,
 				 u32 attr, unsigned long data_size, void *data);
 
-efi_status_t check_var_size(u32 attributes, unsigned long size);
-efi_status_t check_var_size_nonblocking(u32 attributes, unsigned long size);
-
 #if IS_ENABLED(CONFIG_EFI_CAPSULE_LOADER)
 extern bool efi_capsule_pending(int *reset_type);