Merge tag 'efi-urgent' into x86/efi
authorH. Peter Anvin <hpa@linux.intel.com>
Mon, 11 Aug 2014 20:58:54 +0000 (13:58 -0700)
committerH. Peter Anvin <hpa@linux.intel.com>
Mon, 11 Aug 2014 20:58:54 +0000 (13:58 -0700)
 * 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>
1  2 
arch/x86/Kconfig
arch/x86/boot/header.S
drivers/firmware/efi/efi.c
drivers/firmware/efi/libstub/fdt.c

index 7ea8aaaab7fc7d519c411208644a1b3196d8f417,a24097768463aef86644f35f60c97b097d4b6d17..842a5abf3aedd463a3ee7578e9e7986bedfce795
@@@ -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.
Simple merge
Simple merge
index 86d2934840e2c1a4766afdf782a696d6ab2e60f7,0000000000000000000000000000000000000000..a56bb3528755377b8fd6cb29dbd5fcb85692a55d
mode 100644,000000..100644
--- /dev/null
@@@ -1,279 -1,0 +1,279 @@@
-               const char *type, *name;
 +/*
 + * 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;
 +              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;
 +}