Commit ac82d356 authored by Ard Biesheuvel's avatar Ard Biesheuvel Committed by Ingo Molnar
Browse files

efi/libstub/x86: Use ULONG_MAX as upper bound for all allocations 



The header flag XLF_CAN_BE_LOADED_ABOVE_4G will inform us whether
allocations above 4 GiB for kernel, command line, etc are permitted,
so we take it into account when calling efi_allocate_pages() etc.

However, CONFIG_EFI_STUB implies CONFIG_RELOCATABLE, and so the flag
is guaranteed to be set on x86_64 builds, whereas i386 builds are
guaranteed to run under firmware that will not allocate above 4 GB
in the first place.

So drop the check, and just pass ULONG_MAX as the upper bound for
all allocations.

Signed-off-by: default avatarArd Biesheuvel <ardb@kernel.org>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200303225054.28741-1-ardb@kernel.org
Link: https://lore.kernel.org/r/20200308080859.21568-27-ardb@kernel.org
parent 8d8ab66a

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

+4 −13
Original line number Diff line number Diff line
@@ -376,7 +376,6 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle, 
	char *cmdline_ptr;

	unsigned long ramdisk_addr;

	unsigned long ramdisk_size;

	bool above4g;



	sys_table = sys_table_arg;
@@ -394,10 +393,8 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle, 
	image_offset = (void *)startup_32 - image_base;



	hdr = &((struct boot_params *)image_base)->hdr;

	above4g = hdr->xloadflags & XLF_CAN_BE_LOADED_ABOVE_4G;



	status = efi_allocate_pages(0x4000, (unsigned long *)&boot_params,

				    above4g ? ULONG_MAX : UINT_MAX);

	status = efi_allocate_pages(0x4000, (unsigned long *)&boot_params, ULONG_MAX);

	if (status != EFI_SUCCESS) {

		efi_printk("Failed to allocate lowmem for boot params\n");

		efi_exit(handle, status);
@@ -421,8 +418,7 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle, 
	hdr->type_of_loader = 0x21;



	/* Convert unicode cmdline to ascii */

	cmdline_ptr = efi_convert_cmdline(image, &options_size,

					  above4g ? ULONG_MAX : UINT_MAX);

	cmdline_ptr = efi_convert_cmdline(image, &options_size, ULONG_MAX);

	if (!cmdline_ptr)

		goto fail;
@@ -442,8 +438,7 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle, 
			status = efi_load_initrd(image, &ramdisk_addr,

						 &ramdisk_size,

						 hdr->initrd_addr_max,

						 above4g ? ULONG_MAX

							 : hdr->initrd_addr_max);

						 ULONG_MAX);

			if (status != EFI_SUCCESS)

				goto fail2;

			hdr->ramdisk_image = ramdisk_addr & 0xffffffff;
@@ -795,12 +790,8 @@ unsigned long efi_main(efi_handle_t handle, 
	 */

	if (!noinitrd()) {

		unsigned long addr, size;

		unsigned long max_addr = hdr->initrd_addr_max;



		if (hdr->xloadflags & XLF_CAN_BE_LOADED_ABOVE_4G)

			max_addr = ULONG_MAX;



		status = efi_load_initrd_dev_path(&addr, &size, max_addr);

		status = efi_load_initrd_dev_path(&addr, &size, ULONG_MAX);

		if (status == EFI_SUCCESS) {

			hdr->ramdisk_image		= (u32)addr;

			hdr->ramdisk_size 		= (u32)size;

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