From: H. Peter Anvin <hpa@linux.intel.com>
Date: Mon, 11 Aug 2014 20:58:54 +0000 (-0700)
Subject: Merge tag 'efi-urgent' into x86/efi
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=9e13bcf7e0981f1db0c8c8255ac17d5f898903e9;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

Merge tag 'efi-urgent' into x86/efi

 * Enforce CONFIG_RELOCATABLE for the x86 EFI boot stub, otherwise
   it's possible to overwrite random pieces of unallocated memory during
   kernel decompression, leading to machine resets.

Resolved Conflicts:
	arch/x86/Kconfig

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---

9e13bcf7e0981f1db0c8c8255ac17d5f898903e9
diff --cc arch/x86/Kconfig
index 7ea8aaaab7fc,a24097768463..842a5abf3aed
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@@ -1536,7 -1535,8 +1536,8 @@@ config EF
  
  config EFI_STUB
         bool "EFI stub support"
 -       depends on EFI
 +       depends on EFI && !X86_USE_3DNOW
+        select RELOCATABLE
         ---help---
            This kernel feature allows a bzImage to be loaded directly
  	  by EFI firmware without the use of a bootloader.
diff --cc drivers/firmware/efi/libstub/fdt.c
index 86d2934840e2,000000000000..a56bb3528755
mode 100644,000000..100644
--- a/drivers/firmware/efi/libstub/fdt.c
+++ b/drivers/firmware/efi/libstub/fdt.c
@@@ -1,279 -1,0 +1,279 @@@
 +/*
 + * FDT related Helper functions used by the EFI stub on multiple
 + * architectures. This should be #included by the EFI stub
 + * implementation files.
 + *
 + * Copyright 2013 Linaro Limited; author Roy Franz
 + *
 + * This file is part of the Linux kernel, and is made available
 + * under the terms of the GNU General Public License version 2.
 + *
 + */
 +
 +#include <linux/efi.h>
 +#include <linux/libfdt.h>
 +#include <asm/efi.h>
 +
 +efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt,
 +			unsigned long orig_fdt_size,
 +			void *fdt, int new_fdt_size, char *cmdline_ptr,
 +			u64 initrd_addr, u64 initrd_size,
 +			efi_memory_desc_t *memory_map,
 +			unsigned long map_size, unsigned long desc_size,
 +			u32 desc_ver)
 +{
 +	int node, prev;
 +	int status;
 +	u32 fdt_val32;
 +	u64 fdt_val64;
 +
 +	/* Do some checks on provided FDT, if it exists*/
 +	if (orig_fdt) {
 +		if (fdt_check_header(orig_fdt)) {
 +			pr_efi_err(sys_table, "Device Tree header not valid!\n");
 +			return EFI_LOAD_ERROR;
 +		}
 +		/*
 +		 * We don't get the size of the FDT if we get if from a
 +		 * configuration table.
 +		 */
 +		if (orig_fdt_size && fdt_totalsize(orig_fdt) > orig_fdt_size) {
 +			pr_efi_err(sys_table, "Truncated device tree! foo!\n");
 +			return EFI_LOAD_ERROR;
 +		}
 +	}
 +
 +	if (orig_fdt)
 +		status = fdt_open_into(orig_fdt, fdt, new_fdt_size);
 +	else
 +		status = fdt_create_empty_tree(fdt, new_fdt_size);
 +
 +	if (status != 0)
 +		goto fdt_set_fail;
 +
 +	/*
 +	 * Delete any memory nodes present. We must delete nodes which
 +	 * early_init_dt_scan_memory may try to use.
 +	 */
 +	prev = 0;
 +	for (;;) {
- 		const char *type, *name;
++		const char *type;
 +		int len;
 +
 +		node = fdt_next_node(fdt, prev, NULL);
 +		if (node < 0)
 +			break;
 +
 +		type = fdt_getprop(fdt, node, "device_type", &len);
 +		if (type && strncmp(type, "memory", len) == 0) {
 +			fdt_del_node(fdt, node);
 +			continue;
 +		}
 +
 +		prev = node;
 +	}
 +
 +	node = fdt_subnode_offset(fdt, 0, "chosen");
 +	if (node < 0) {
 +		node = fdt_add_subnode(fdt, 0, "chosen");
 +		if (node < 0) {
 +			status = node; /* node is error code when negative */
 +			goto fdt_set_fail;
 +		}
 +	}
 +
 +	if ((cmdline_ptr != NULL) && (strlen(cmdline_ptr) > 0)) {
 +		status = fdt_setprop(fdt, node, "bootargs", cmdline_ptr,
 +				     strlen(cmdline_ptr) + 1);
 +		if (status)
 +			goto fdt_set_fail;
 +	}
 +
 +	/* Set initrd address/end in device tree, if present */
 +	if (initrd_size != 0) {
 +		u64 initrd_image_end;
 +		u64 initrd_image_start = cpu_to_fdt64(initrd_addr);
 +
 +		status = fdt_setprop(fdt, node, "linux,initrd-start",
 +				     &initrd_image_start, sizeof(u64));
 +		if (status)
 +			goto fdt_set_fail;
 +		initrd_image_end = cpu_to_fdt64(initrd_addr + initrd_size);
 +		status = fdt_setprop(fdt, node, "linux,initrd-end",
 +				     &initrd_image_end, sizeof(u64));
 +		if (status)
 +			goto fdt_set_fail;
 +	}
 +
 +	/* Add FDT entries for EFI runtime services in chosen node. */
 +	node = fdt_subnode_offset(fdt, 0, "chosen");
 +	fdt_val64 = cpu_to_fdt64((u64)(unsigned long)sys_table);
 +	status = fdt_setprop(fdt, node, "linux,uefi-system-table",
 +			     &fdt_val64, sizeof(fdt_val64));
 +	if (status)
 +		goto fdt_set_fail;
 +
 +	fdt_val64 = cpu_to_fdt64((u64)(unsigned long)memory_map);
 +	status = fdt_setprop(fdt, node, "linux,uefi-mmap-start",
 +			     &fdt_val64,  sizeof(fdt_val64));
 +	if (status)
 +		goto fdt_set_fail;
 +
 +	fdt_val32 = cpu_to_fdt32(map_size);
 +	status = fdt_setprop(fdt, node, "linux,uefi-mmap-size",
 +			     &fdt_val32,  sizeof(fdt_val32));
 +	if (status)
 +		goto fdt_set_fail;
 +
 +	fdt_val32 = cpu_to_fdt32(desc_size);
 +	status = fdt_setprop(fdt, node, "linux,uefi-mmap-desc-size",
 +			     &fdt_val32, sizeof(fdt_val32));
 +	if (status)
 +		goto fdt_set_fail;
 +
 +	fdt_val32 = cpu_to_fdt32(desc_ver);
 +	status = fdt_setprop(fdt, node, "linux,uefi-mmap-desc-ver",
 +			     &fdt_val32, sizeof(fdt_val32));
 +	if (status)
 +		goto fdt_set_fail;
 +
 +	/*
 +	 * Add kernel version banner so stub/kernel match can be
 +	 * verified.
 +	 */
 +	status = fdt_setprop_string(fdt, node, "linux,uefi-stub-kern-ver",
 +			     linux_banner);
 +	if (status)
 +		goto fdt_set_fail;
 +
 +	return EFI_SUCCESS;
 +
 +fdt_set_fail:
 +	if (status == -FDT_ERR_NOSPACE)
 +		return EFI_BUFFER_TOO_SMALL;
 +
 +	return EFI_LOAD_ERROR;
 +}
 +
 +#ifndef EFI_FDT_ALIGN
 +#define EFI_FDT_ALIGN EFI_PAGE_SIZE
 +#endif
 +
 +/*
 + * Allocate memory for a new FDT, then add EFI, commandline, and
 + * initrd related fields to the FDT.  This routine increases the
 + * FDT allocation size until the allocated memory is large
 + * enough.  EFI allocations are in EFI_PAGE_SIZE granules,
 + * which are fixed at 4K bytes, so in most cases the first
 + * allocation should succeed.
 + * EFI boot services are exited at the end of this function.
 + * There must be no allocations between the get_memory_map()
 + * call and the exit_boot_services() call, so the exiting of
 + * boot services is very tightly tied to the creation of the FDT
 + * with the final memory map in it.
 + */
 +
 +efi_status_t allocate_new_fdt_and_exit_boot(efi_system_table_t *sys_table,
 +					    void *handle,
 +					    unsigned long *new_fdt_addr,
 +					    unsigned long max_addr,
 +					    u64 initrd_addr, u64 initrd_size,
 +					    char *cmdline_ptr,
 +					    unsigned long fdt_addr,
 +					    unsigned long fdt_size)
 +{
 +	unsigned long map_size, desc_size;
 +	u32 desc_ver;
 +	unsigned long mmap_key;
 +	efi_memory_desc_t *memory_map;
 +	unsigned long new_fdt_size;
 +	efi_status_t status;
 +
 +	/*
 +	 * Estimate size of new FDT, and allocate memory for it. We
 +	 * will allocate a bigger buffer if this ends up being too
 +	 * small, so a rough guess is OK here.
 +	 */
 +	new_fdt_size = fdt_size + EFI_PAGE_SIZE;
 +	while (1) {
 +		status = efi_high_alloc(sys_table, new_fdt_size, EFI_FDT_ALIGN,
 +					new_fdt_addr, max_addr);
 +		if (status != EFI_SUCCESS) {
 +			pr_efi_err(sys_table, "Unable to allocate memory for new device tree.\n");
 +			goto fail;
 +		}
 +
 +		/*
 +		 * Now that we have done our final memory allocation (and free)
 +		 * we can get the memory map key  needed for
 +		 * exit_boot_services().
 +		 */
 +		status = efi_get_memory_map(sys_table, &memory_map, &map_size,
 +					    &desc_size, &desc_ver, &mmap_key);
 +		if (status != EFI_SUCCESS)
 +			goto fail_free_new_fdt;
 +
 +		status = update_fdt(sys_table,
 +				    (void *)fdt_addr, fdt_size,
 +				    (void *)*new_fdt_addr, new_fdt_size,
 +				    cmdline_ptr, initrd_addr, initrd_size,
 +				    memory_map, map_size, desc_size, desc_ver);
 +
 +		/* Succeeding the first time is the expected case. */
 +		if (status == EFI_SUCCESS)
 +			break;
 +
 +		if (status == EFI_BUFFER_TOO_SMALL) {
 +			/*
 +			 * We need to allocate more space for the new
 +			 * device tree, so free existing buffer that is
 +			 * too small.  Also free memory map, as we will need
 +			 * to get new one that reflects the free/alloc we do
 +			 * on the device tree buffer.
 +			 */
 +			efi_free(sys_table, new_fdt_size, *new_fdt_addr);
 +			sys_table->boottime->free_pool(memory_map);
 +			new_fdt_size += EFI_PAGE_SIZE;
 +		} else {
 +			pr_efi_err(sys_table, "Unable to constuct new device tree.\n");
 +			goto fail_free_mmap;
 +		}
 +	}
 +
 +	/* Now we are ready to exit_boot_services.*/
 +	status = sys_table->boottime->exit_boot_services(handle, mmap_key);
 +
 +
 +	if (status == EFI_SUCCESS)
 +		return status;
 +
 +	pr_efi_err(sys_table, "Exit boot services failed.\n");
 +
 +fail_free_mmap:
 +	sys_table->boottime->free_pool(memory_map);
 +
 +fail_free_new_fdt:
 +	efi_free(sys_table, new_fdt_size, *new_fdt_addr);
 +
 +fail:
 +	return EFI_LOAD_ERROR;
 +}
 +
 +void *get_fdt(efi_system_table_t *sys_table)
 +{
 +	efi_guid_t fdt_guid = DEVICE_TREE_GUID;
 +	efi_config_table_t *tables;
 +	void *fdt;
 +	int i;
 +
 +	tables = (efi_config_table_t *) sys_table->tables;
 +	fdt = NULL;
 +
 +	for (i = 0; i < sys_table->nr_tables; i++)
 +		if (efi_guidcmp(tables[i].guid, fdt_guid) == 0) {
 +			fdt = (void *) tables[i].table;
 +			break;
 +	 }
 +
 +	return fdt;
 +}