File 0002-Fix-Werror-array-bounds-array-subscript-0-... of Package grub2

Overview Repositories Revisions Requests Users Attributes Meta

File 0002-Fix-Werror-array-bounds-array-subscript-0-is-outside.patch of Package grub2 (Revision 421a5cf0a3cd4035b72848e13245b74c)

Currently displaying revision 421a5cf0a3cd4035b72848e13245b74c , Show latest

From 04de53cb4adc0ae6429b0715c3f1dd8a62ff9a0f Mon Sep 17 00:00:00 2001
From: Michael Chang <mchang@suse.com>
Date: Wed, 16 Mar 2022 17:05:01 +0800
Subject: [PATCH 2/3] Fix -Werror=array-bounds array subscript 0 is outside
 array bounds

The grub is failing to build with gcc-12 in many places like this:

In function 'init_cbfsdisk',
    inlined from 'grub_mod_init' at ../../grub-core/fs/cbfs.c:391:3:
../../grub-core/fs/cbfs.c:345:7: error: array subscript 0 is outside array bounds of 'grub_uint32_t[0]' {aka 'unsigned int[]'} [-Werror=array-bounds]
  345 |   ptr = *(grub_uint32_t *) 0xfffffffc;
      |   ~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This is caused by gcc regression in 11/12 [1]. In a nut shell, the
warning is about detected invalid accesses at non-zero offsets to null
pointers. Since hardwired constant address is treated as NULL plus an
offset in the same underlying code, the warning is therefore triggered.

Instead of inserting #pragma all over the places where literal pointers
are accessed to avoid diagnosing array-bounds, we can try to borrow the
idea from linux kernel that the absolute_pointer macro [2][3] is used to
disconnect a pointer using literal address from it's original object,
hence gcc won't be able to make assumptions on the boundary while doing
pointer arithmetic. With that we can greatly reduce the code we have to
cover up by making initial literal pointer assignment to use the new
wrapper but not having to track everywhere literal pointers are
accessed. This also makes code looks cleaner.

[1]
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99578
[2]
https://elixir.bootlin.com/linux/v5.16.14/source/include/linux/compiler.h#L180
[3]
https://elixir.bootlin.com/linux/v5.16.14/source/include/linux/compiler-gcc.h#L31

Signed-off-by: Michael Chang <mchang@suse.com>
---
 grub-core/bus/cs5536.c                |  4 ++--
 grub-core/commands/acpi.c             |  4 ++--
 grub-core/commands/efi/loadbios.c     |  9 +++++----
 grub-core/commands/i386/pc/drivemap.c |  9 ++++++---
 grub-core/commands/i386/pc/sendkey.c  | 12 ++++++------
 grub-core/disk/i386/pc/biosdisk.c     |  4 ++--
 grub-core/fs/cbfs.c                   |  2 +-
 grub-core/kern/i386/pc/acpi.c         |  4 ++--
 grub-core/kern/i386/pc/mmap.c         |  2 +-
 grub-core/loader/i386/multiboot_mbi.c |  2 +-
 grub-core/loader/multiboot_mbi2.c     |  4 ++--
 grub-core/mmap/i386/pc/mmap.c         | 26 +++++++++++++-------------
 grub-core/net/drivers/i386/pc/pxe.c   | 12 ++++++------
 grub-core/term/i386/pc/console.c      |  5 ++---
 grub-core/term/i386/pc/vga_text.c     |  6 +++---
 grub-core/term/ns8250.c               |  7 ++++++-
 grub-core/video/i386/pc/vbe.c         |  6 +++---
 include/grub/compiler.h               | 11 +++++++++++
 18 files changed, 74 insertions(+), 55 deletions(-)

diff --git a/grub-core/bus/cs5536.c b/grub-core/bus/cs5536.c
index bb9aa27e5b..bccaeeeccb 100644
--- a/grub-core/bus/cs5536.c
+++ b/grub-core/bus/cs5536.c
@@ -331,8 +331,8 @@ grub_cs5536_init_geode (grub_pci_device_t dev)
 
   {
     volatile grub_uint32_t *oc;
-    oc = grub_pci_device_map_range (dev, 0x05022000,
-				    GRUB_CS5536_USB_OPTION_REGS_SIZE);
+    oc = grub_absolute_pointer (grub_pci_device_map_range (dev, 0x05022000,
+				    GRUB_CS5536_USB_OPTION_REGS_SIZE));
 
     oc[GRUB_CS5536_USB_OPTION_REG_UOCMUX] =
       (oc[GRUB_CS5536_USB_OPTION_REG_UOCMUX]
diff --git a/grub-core/commands/acpi.c b/grub-core/commands/acpi.c
index 1215f2a62e..4721730b39 100644
--- a/grub-core/commands/acpi.c
+++ b/grub-core/commands/acpi.c
@@ -168,7 +168,7 @@ grub_acpi_create_ebda (void)
   struct grub_acpi_rsdp_v10 *v1;
   struct grub_acpi_rsdp_v20 *v2;
 
-  ebda = (grub_uint8_t *) (grub_addr_t) ((*((grub_uint16_t *)0x40e)) << 4);
+  ebda = (grub_uint8_t *) (grub_addr_t) ((*((grub_uint16_t *)grub_absolute_pointer(0x40e))) << 4);
   grub_dprintf ("acpi", "EBDA @%p\n", ebda);
   if (ebda)
     ebda_kb_len = *(grub_uint16_t *) ebda;
@@ -298,7 +298,7 @@ grub_acpi_create_ebda (void)
       *target = 0;
 
   grub_dprintf ("acpi", "Switching EBDA\n");
-  (*((grub_uint16_t *) 0x40e)) = ((grub_addr_t) targetebda) >> 4;
+  (*((grub_uint16_t *) grub_absolute_pointer(0x40e))) = ((grub_addr_t) targetebda) >> 4;
   grub_dprintf ("acpi", "EBDA switched\n");
 
   return GRUB_ERR_NONE;
diff --git a/grub-core/commands/efi/loadbios.c b/grub-core/commands/efi/loadbios.c
index 5c7725f8bd..574e410466 100644
--- a/grub-core/commands/efi/loadbios.c
+++ b/grub-core/commands/efi/loadbios.c
@@ -46,7 +46,7 @@ enable_rom_area (void)
   grub_uint32_t *rom_ptr;
   grub_pci_device_t dev = { .bus = 0, .device = 0, .function = 0};
 
-  rom_ptr = (grub_uint32_t *) VBIOS_ADDR;
+  rom_ptr = grub_absolute_pointer (VBIOS_ADDR);
   if (*rom_ptr != BLANK_MEM)
     {
       grub_puts_ (N_("ROM image is present."));
@@ -96,8 +96,8 @@ fake_bios_data (int use_rom)
   void *acpi, *smbios;
   grub_uint16_t *ebda_seg_ptr, *low_mem_ptr;
 
-  ebda_seg_ptr = (grub_uint16_t *) EBDA_SEG_ADDR;
-  low_mem_ptr = (grub_uint16_t *) LOW_MEM_ADDR;
+  ebda_seg_ptr = grub_absolute_pointer (EBDA_SEG_ADDR);
+  low_mem_ptr = grub_absolute_pointer (LOW_MEM_ADDR);
   if ((*ebda_seg_ptr) || (*low_mem_ptr))
     return;
 
@@ -132,7 +132,8 @@ fake_bios_data (int use_rom)
   *ebda_seg_ptr = FAKE_EBDA_SEG;
   *low_mem_ptr = (FAKE_EBDA_SEG >> 6);
 
-  *((grub_uint16_t *) (FAKE_EBDA_SEG << 4)) = 640 - *low_mem_ptr;
+  /* *((grub_uint16_t *) (FAKE_EBDA_SEG << 4)) = 640 - *low_mem_ptr; */
+  *((grub_uint16_t *) (grub_absolute_pointer (FAKE_EBDA_SEG << 4))) = 640 - *low_mem_ptr;
 
   if (acpi)
     grub_memcpy ((char *) ((FAKE_EBDA_SEG << 4) + 16), acpi, 1024 - 16);
diff --git a/grub-core/commands/i386/pc/drivemap.c b/grub-core/commands/i386/pc/drivemap.c
index 7f7f2d41c0..6a4d923613 100644
--- a/grub-core/commands/i386/pc/drivemap.c
+++ b/grub-core/commands/i386/pc/drivemap.c
@@ -31,9 +31,6 @@
 
 GRUB_MOD_LICENSE ("GPLv3+");
 
-/* Real mode IVT slot (seg:off far pointer) for interrupt 0x13.  */
-static grub_uint32_t *const int13slot = (grub_uint32_t *) (4 * 0x13);
-
 /* Remember to update enum opt_idxs accordingly.  */
 static const struct grub_arg_option options[] = {
   /* TRANSLATORS: In this file "mapping" refers to a change GRUB makes so if
@@ -280,6 +277,9 @@ install_int13_handler (int noret __attribute__ ((unused)))
   grub_uint8_t *handler_base = 0;
   /* Address of the map within the deployed bundle.  */
   int13map_node_t *handler_map;
+  /* Real mode IVT slot (seg:off far pointer) for interrupt 0x13.  */
+  grub_uint32_t *int13slot = (grub_uint32_t *) grub_absolute_pointer (4 * 0x13);
+
 
   int i;
   int entries = 0;
@@ -354,6 +354,9 @@ install_int13_handler (int noret __attribute__ ((unused)))
 static grub_err_t
 uninstall_int13_handler (void)
 {
+  /* Real mode IVT slot (seg:off far pointer) for interrupt 0x13.  */
+  grub_uint32_t *int13slot = (grub_uint32_t *) grub_absolute_pointer (4 * 0x13);
+
   if (! grub_drivemap_oldhandler)
     return GRUB_ERR_NONE;
 
diff --git a/grub-core/commands/i386/pc/sendkey.c b/grub-core/commands/i386/pc/sendkey.c
index 26d9acd3de..532a66497f 100644
--- a/grub-core/commands/i386/pc/sendkey.c
+++ b/grub-core/commands/i386/pc/sendkey.c
@@ -216,12 +216,12 @@ static grub_err_t
 grub_sendkey_postboot (void)
 {
   /* For convention: pointer to flags.  */
-  grub_uint32_t *flags = (grub_uint32_t *) 0x417;
+  grub_uint32_t *flags = grub_absolute_pointer (0x417);
 
   *flags = oldflags;
 
-  *((char *) 0x41a) = 0x1e;
-  *((char *) 0x41c) = 0x1e;
+  *((char *) grub_absolute_pointer (0x41a)) = 0x1e;
+  *((char *) grub_absolute_pointer (0x41c)) = 0x1e;
 
   return GRUB_ERR_NONE;
 }
@@ -231,13 +231,13 @@ static grub_err_t
 grub_sendkey_preboot (int noret __attribute__ ((unused)))
 {
   /* For convention: pointer to flags.  */
-  grub_uint32_t *flags = (grub_uint32_t *) 0x417;
+  grub_uint32_t *flags = grub_absolute_pointer (0x417);
 
   oldflags = *flags;
   
   /* Set the sendkey.  */
-  *((char *) 0x41a) = 0x1e;
-  *((char *) 0x41c) = keylen + 0x1e;
+  *((char *) grub_absolute_pointer (0x41a)) = 0x1e;
+  *((char *) grub_absolute_pointer (0x41c)) = keylen + 0x1e;
   grub_memcpy ((char *) 0x41e, sendkey, 0x20);
 
   /* Transform "any ctrl" to "right ctrl" flag.  */
diff --git a/grub-core/disk/i386/pc/biosdisk.c b/grub-core/disk/i386/pc/biosdisk.c
index 8ca250c77b..89746ed940 100644
--- a/grub-core/disk/i386/pc/biosdisk.c
+++ b/grub-core/disk/i386/pc/biosdisk.c
@@ -367,7 +367,7 @@ grub_biosdisk_open (const char *name, grub_disk_t disk)
       if (version)
 	{
 	  struct grub_biosdisk_drp *drp
-	    = (struct grub_biosdisk_drp *) GRUB_MEMORY_MACHINE_SCRATCH_ADDR;
+	    = (struct grub_biosdisk_drp *) grub_absolute_pointer (GRUB_MEMORY_MACHINE_SCRATCH_ADDR);
 
 	  /* Clear out the DRP.  */
 	  grub_memset (drp, 0, sizeof (*drp));
@@ -654,7 +654,7 @@ grub_disk_biosdisk_fini (void)
 GRUB_MOD_INIT(biosdisk)
 {
   struct grub_biosdisk_cdrp *cdrp
-    = (struct grub_biosdisk_cdrp *) GRUB_MEMORY_MACHINE_SCRATCH_ADDR;
+    = (struct grub_biosdisk_cdrp *) grub_absolute_pointer (GRUB_MEMORY_MACHINE_SCRATCH_ADDR);
   grub_uint8_t boot_drive;
 
   if (grub_disk_firmware_is_tainted)
diff --git a/grub-core/fs/cbfs.c b/grub-core/fs/cbfs.c
index 581215ef18..8ab7106afb 100644
--- a/grub-core/fs/cbfs.c
+++ b/grub-core/fs/cbfs.c
@@ -342,7 +342,7 @@ init_cbfsdisk (void)
   grub_uint32_t ptr;
   struct cbfs_header *head;
 
-  ptr = *(grub_uint32_t *) 0xfffffffc;
+  ptr = *((grub_uint32_t *) grub_absolute_pointer (0xfffffffc));
   head = (struct cbfs_header *) (grub_addr_t) ptr;
   grub_dprintf ("cbfs", "head=%p\n", head);
 
diff --git a/grub-core/kern/i386/pc/acpi.c b/grub-core/kern/i386/pc/acpi.c
index 297f5d05f3..0a69eba7b5 100644
--- a/grub-core/kern/i386/pc/acpi.c
+++ b/grub-core/kern/i386/pc/acpi.c
@@ -27,7 +27,7 @@ grub_machine_acpi_get_rsdpv1 (void)
   grub_uint8_t *ebda, *ptr;
 
   grub_dprintf ("acpi", "Looking for RSDP. Scanning EBDA\n");
-  ebda = (grub_uint8_t *) ((* ((grub_uint16_t *) 0x40e)) << 4);
+  ebda = (grub_uint8_t *) ((* ((grub_uint16_t *) grub_absolute_pointer (0x40e))) << 4);
   ebda_len = * (grub_uint16_t *) ebda;
   if (! ebda_len) /* FIXME do we really need this check? */
     goto scan_bios;
@@ -55,7 +55,7 @@ grub_machine_acpi_get_rsdpv2 (void)
   grub_uint8_t *ebda, *ptr;
 
   grub_dprintf ("acpi", "Looking for RSDP. Scanning EBDA\n");
-  ebda = (grub_uint8_t *) ((* ((grub_uint16_t *) 0x40e)) << 4);
+  ebda = (grub_uint8_t *) ((* ((grub_uint16_t *) grub_absolute_pointer (0x40e))) << 4);
   ebda_len = * (grub_uint16_t *) ebda;
   if (! ebda_len) /* FIXME do we really need this check? */
     goto scan_bios;
diff --git a/grub-core/kern/i386/pc/mmap.c b/grub-core/kern/i386/pc/mmap.c
index c0c3c35858..a4a1a75af4 100644
--- a/grub-core/kern/i386/pc/mmap.c
+++ b/grub-core/kern/i386/pc/mmap.c
@@ -143,7 +143,7 @@ grub_machine_mmap_iterate (grub_memory_hook_t hook, void *hook_data)
 {
   grub_uint32_t cont = 0;
   struct grub_machine_mmap_entry *entry
-    = (struct grub_machine_mmap_entry *) GRUB_MEMORY_MACHINE_SCRATCH_ADDR;
+    = (struct grub_machine_mmap_entry *) grub_absolute_pointer (GRUB_MEMORY_MACHINE_SCRATCH_ADDR);
   int e820_works = 0;
 
   while (1)
diff --git a/grub-core/loader/i386/multiboot_mbi.c b/grub-core/loader/i386/multiboot_mbi.c
index a67d9d0a80..434e694ffb 100644
--- a/grub-core/loader/i386/multiboot_mbi.c
+++ b/grub-core/loader/i386/multiboot_mbi.c
@@ -293,7 +293,7 @@ fill_vbe_info (struct multiboot_info *mbi, grub_uint8_t *ptrorig,
   struct grub_vbe_mode_info_block *mode_info;
 #if GRUB_MACHINE_HAS_VBE
   grub_vbe_status_t status;
-  void *scratch = (void *) GRUB_MEMORY_MACHINE_SCRATCH_ADDR;
+  void *scratch = grub_absolute_pointer (GRUB_MEMORY_MACHINE_SCRATCH_ADDR);
     
   status = grub_vbe_bios_get_controller_info (scratch);
   if (status != GRUB_VBE_STATUS_OK)
diff --git a/grub-core/loader/multiboot_mbi2.c b/grub-core/loader/multiboot_mbi2.c
index 9a943d7bdd..2ad210e7f9 100644
--- a/grub-core/loader/multiboot_mbi2.c
+++ b/grub-core/loader/multiboot_mbi2.c
@@ -504,7 +504,7 @@ static void
 fill_vbe_tag (struct multiboot_tag_vbe *tag)
 {
   grub_vbe_status_t status;
-  void *scratch = (void *) GRUB_MEMORY_MACHINE_SCRATCH_ADDR;
+  void *scratch = grub_absolute_pointer (GRUB_MEMORY_MACHINE_SCRATCH_ADDR);
 
   tag->type = MULTIBOOT_TAG_TYPE_VBE;
   tag->size = 0;
@@ -577,7 +577,7 @@ retrieve_video_parameters (grub_properly_aligned_t **ptrorig)
 #if defined (GRUB_MACHINE_PCBIOS)
       {
 	grub_vbe_status_t status;
-	void *scratch = (void *) GRUB_MEMORY_MACHINE_SCRATCH_ADDR;
+	void *scratch = grub_absolute_pointer (GRUB_MEMORY_MACHINE_SCRATCH_ADDR);
 	status = grub_vbe_bios_get_mode (scratch);
 	vbe_mode = *(grub_uint32_t *) scratch;
 	if (status != GRUB_VBE_STATUS_OK)
diff --git a/grub-core/mmap/i386/pc/mmap.c b/grub-core/mmap/i386/pc/mmap.c
index 6ab4f67309..b9c5b0a002 100644
--- a/grub-core/mmap/i386/pc/mmap.c
+++ b/grub-core/mmap/i386/pc/mmap.c
@@ -80,13 +80,13 @@ preboot (int noreturn __attribute__ ((unused)))
     = min (grub_mmap_get_post64 (), 0xfc000000ULL) >> 16;
 
   /* Correct BDA. */
-  *((grub_uint16_t *) 0x413) = grub_mmap_get_lower () >> 10;
+  *((grub_uint16_t *) grub_absolute_pointer (0x413)) = grub_mmap_get_lower () >> 10;
 
   /* Save old interrupt handlers. */
-  grub_machine_mmaphook_int12offset = *((grub_uint16_t *) 0x48);
-  grub_machine_mmaphook_int12segment = *((grub_uint16_t *) 0x4a);
-  grub_machine_mmaphook_int15offset = *((grub_uint16_t *) 0x54);
-  grub_machine_mmaphook_int15segment = *((grub_uint16_t *) 0x56);
+  grub_machine_mmaphook_int12offset = *((grub_uint16_t *) grub_absolute_pointer (0x48));
+  grub_machine_mmaphook_int12segment = *((grub_uint16_t *) grub_absolute_pointer (0x4a));
+  grub_machine_mmaphook_int15offset = *((grub_uint16_t *) grub_absolute_pointer (0x54));
+  grub_machine_mmaphook_int15segment = *((grub_uint16_t *) grub_absolute_pointer (0x56));
 
   grub_dprintf ("mmap", "hooktarget = %p\n", hooktarget);
 
@@ -94,11 +94,11 @@ preboot (int noreturn __attribute__ ((unused)))
   grub_memcpy (hooktarget, &grub_machine_mmaphook_start,
 	       &grub_machine_mmaphook_end - &grub_machine_mmaphook_start);
 
-  *((grub_uint16_t *) 0x4a) = ((grub_addr_t) hooktarget) >> 4;
-  *((grub_uint16_t *) 0x56) = ((grub_addr_t) hooktarget) >> 4;
-  *((grub_uint16_t *) 0x48) = &grub_machine_mmaphook_int12
+  *((grub_uint16_t *) grub_absolute_pointer (0x4a)) = ((grub_addr_t) hooktarget) >> 4;
+  *((grub_uint16_t *) grub_absolute_pointer (0x56)) = ((grub_addr_t) hooktarget) >> 4;
+  *((grub_uint16_t *) grub_absolute_pointer (0x48)) = &grub_machine_mmaphook_int12
     - &grub_machine_mmaphook_start;
-  *((grub_uint16_t *) 0x54) = &grub_machine_mmaphook_int15
+  *((grub_uint16_t *) grub_absolute_pointer (0x54)) = &grub_machine_mmaphook_int15
     - &grub_machine_mmaphook_start;
 
   return GRUB_ERR_NONE;
@@ -108,10 +108,10 @@ static grub_err_t
 preboot_rest (void)
 {
   /* Restore old interrupt handlers. */
-  *((grub_uint16_t *) 0x48) = grub_machine_mmaphook_int12offset;
-  *((grub_uint16_t *) 0x4a) = grub_machine_mmaphook_int12segment;
-  *((grub_uint16_t *) 0x54) = grub_machine_mmaphook_int15offset;
-  *((grub_uint16_t *) 0x56) = grub_machine_mmaphook_int15segment;
+  *((grub_uint16_t *) grub_absolute_pointer (0x48)) = grub_machine_mmaphook_int12offset;
+  *((grub_uint16_t *) grub_absolute_pointer (0x4a)) = grub_machine_mmaphook_int12segment;
+  *((grub_uint16_t *) grub_absolute_pointer (0x54)) = grub_machine_mmaphook_int15offset;
+  *((grub_uint16_t *) grub_absolute_pointer (0x56)) = grub_machine_mmaphook_int15segment;
 
   return GRUB_ERR_NONE;
 }
diff --git a/grub-core/net/drivers/i386/pc/pxe.c b/grub-core/net/drivers/i386/pc/pxe.c
index 3f4152d036..313ed250e8 100644
--- a/grub-core/net/drivers/i386/pc/pxe.c
+++ b/grub-core/net/drivers/i386/pc/pxe.c
@@ -174,7 +174,7 @@ grub_pxe_recv (struct grub_net_card *dev __attribute__ ((unused)))
   grub_uint8_t *ptr, *end;
   struct grub_net_buff *buf;
 
-  isr = (void *) GRUB_MEMORY_MACHINE_SCRATCH_ADDR;
+  isr = (void *) grub_absolute_pointer (GRUB_MEMORY_MACHINE_SCRATCH_ADDR);
 
   if (!in_progress)
     {
@@ -256,11 +256,11 @@ grub_pxe_send (struct grub_net_card *dev __attribute__ ((unused)),
   struct grub_pxe_undi_tbd *tbd;
   char *buf;
 
-  trans = (void *) GRUB_MEMORY_MACHINE_SCRATCH_ADDR;
+  trans = (void *) grub_absolute_pointer (GRUB_MEMORY_MACHINE_SCRATCH_ADDR);
   grub_memset (trans, 0, sizeof (*trans));
-  tbd = (void *) (GRUB_MEMORY_MACHINE_SCRATCH_ADDR + 128);
+  tbd = (void *) grub_absolute_pointer (GRUB_MEMORY_MACHINE_SCRATCH_ADDR + 128);
   grub_memset (tbd, 0, sizeof (*tbd));
-  buf = (void *) (GRUB_MEMORY_MACHINE_SCRATCH_ADDR + 256);
+  buf = (void *) grub_absolute_pointer (GRUB_MEMORY_MACHINE_SCRATCH_ADDR + 256);
   grub_memcpy (buf, pack->data, pack->tail - pack->data);
 
   trans->tbd = SEGOFS ((grub_addr_t) tbd);
@@ -287,7 +287,7 @@ static grub_err_t
 grub_pxe_open (struct grub_net_card *dev __attribute__ ((unused)))
 {
   struct grub_pxe_undi_open *ou;
-  ou = (void *) GRUB_MEMORY_MACHINE_SCRATCH_ADDR;
+  ou = (void *) grub_absolute_pointer (GRUB_MEMORY_MACHINE_SCRATCH_ADDR);
   grub_memset (ou, 0, sizeof (*ou));
   ou->pkt_filter = 4;
   grub_pxe_call (GRUB_PXENV_UNDI_OPEN, ou, pxe_rm_entry);
@@ -382,7 +382,7 @@ GRUB_MOD_INIT(pxe)
   if (! pxenv)
     return;
 
-  ui = (void *) GRUB_MEMORY_MACHINE_SCRATCH_ADDR;
+  ui = (void *) grub_absolute_pointer (GRUB_MEMORY_MACHINE_SCRATCH_ADDR);
   grub_memset (ui, 0, sizeof (*ui));
   grub_pxe_call (GRUB_PXENV_UNDI_GET_INFORMATION, ui, pxe_rm_entry);
 
diff --git a/grub-core/term/i386/pc/console.c b/grub-core/term/i386/pc/console.c
index f6142a2dea..d70ee4af05 100644
--- a/grub-core/term/i386/pc/console.c
+++ b/grub-core/term/i386/pc/console.c
@@ -238,12 +238,11 @@ grub_console_getkey (struct grub_term_input *term __attribute__ ((unused)))
   return (regs.eax & 0xff) + (('a' - 1) | GRUB_TERM_CTRL);
 }
 
-static const struct grub_machine_bios_data_area *bios_data_area =
-  (struct grub_machine_bios_data_area *) GRUB_MEMORY_MACHINE_BIOS_DATA_AREA_ADDR;
-
 static int
 grub_console_getkeystatus (struct grub_term_input *term __attribute__ ((unused)))
 {
+  const struct grub_machine_bios_data_area *bios_data_area =
+  (struct grub_machine_bios_data_area *) grub_absolute_pointer (GRUB_MEMORY_MACHINE_BIOS_DATA_AREA_ADDR);
   /* conveniently GRUB keystatus is modelled after BIOS one.  */
   return bios_data_area->keyboard_flag_lower & ~0x80;
 }
diff --git a/grub-core/term/i386/pc/vga_text.c b/grub-core/term/i386/pc/vga_text.c
index 88fecc5ea5..669d06fad7 100644
--- a/grub-core/term/i386/pc/vga_text.c
+++ b/grub-core/term/i386/pc/vga_text.c
@@ -45,15 +45,15 @@ GRUB_MOD_LICENSE ("GPLv3+");
 static struct grub_term_coordinate grub_curr_pos;
 
 #ifdef __mips__
-#define VGA_TEXT_SCREEN		((grub_uint16_t *) 0xb00b8000)
+#define VGA_TEXT_SCREEN		((grub_uint16_t *) grub_absolute_pointer (0xb00b8000))
 #define cr_read grub_vga_cr_read
 #define cr_write grub_vga_cr_write
 #elif defined (MODE_MDA)
-#define VGA_TEXT_SCREEN		((grub_uint16_t *) 0xb0000)
+#define VGA_TEXT_SCREEN		((grub_uint16_t *) grub_absolute_pointer (0xb0000))
 #define cr_read grub_vga_cr_bw_read
 #define cr_write grub_vga_cr_bw_write
 #else
-#define VGA_TEXT_SCREEN		((grub_uint16_t *) 0xb8000)
+#define VGA_TEXT_SCREEN		((grub_uint16_t *) grub_absolute_pointer (0xb8000))
 #define cr_read grub_vga_cr_read
 #define cr_write grub_vga_cr_write
 #endif
diff --git a/grub-core/term/ns8250.c b/grub-core/term/ns8250.c
index 39809d0423..622670d179 100644
--- a/grub-core/term/ns8250.c
+++ b/grub-core/term/ns8250.c
@@ -28,7 +28,6 @@
 
 #ifdef GRUB_MACHINE_PCBIOS
 #include <grub/machine/memory.h>
-static const unsigned short *serial_hw_io_addr = (const unsigned short *) GRUB_MEMORY_MACHINE_BIOS_DATA_AREA_ADDR;
 #define GRUB_SERIAL_PORT_NUM 4
 #else
 #include <grub/machine/serial.h>
@@ -237,6 +236,9 @@ static struct grub_serial_port com_ports[GRUB_SERIAL_PORT_NUM];
 void
 grub_ns8250_init (void)
 {
+#ifdef GRUB_MACHINE_PCBIOS
+  const unsigned short *serial_hw_io_addr = (const unsigned short *) grub_absolute_pointer (GRUB_MEMORY_MACHINE_BIOS_DATA_AREA_ADDR);
+#endif
   unsigned i;
   for (i = 0; i < GRUB_SERIAL_PORT_NUM; i++)
     if (serial_hw_io_addr[i])
@@ -272,6 +274,9 @@ grub_ns8250_init (void)
 grub_port_t
 grub_ns8250_hw_get_port (const unsigned int unit)
 {
+#ifdef GRUB_MACHINE_PCBIOS
+  const unsigned short *serial_hw_io_addr = (const unsigned short *) grub_absolute_pointer (GRUB_MEMORY_MACHINE_BIOS_DATA_AREA_ADDR);
+#endif
   if (unit < GRUB_SERIAL_PORT_NUM
       && !(dead_ports & (1 << unit)))
     return serial_hw_io_addr[unit];
diff --git a/grub-core/video/i386/pc/vbe.c b/grub-core/video/i386/pc/vbe.c
index 68700ecda1..8c8cbf07eb 100644
--- a/grub-core/video/i386/pc/vbe.c
+++ b/grub-core/video/i386/pc/vbe.c
@@ -514,7 +514,7 @@ grub_vbe_probe (struct grub_vbe_info_block *info_block)
 
       /* Use low memory scratch area as temporary storage
          for VESA BIOS call.  */
-      vbe_ib = (struct grub_vbe_info_block *) GRUB_MEMORY_MACHINE_SCRATCH_ADDR;
+      vbe_ib = (struct grub_vbe_info_block *) grub_absolute_pointer (GRUB_MEMORY_MACHINE_SCRATCH_ADDR);
 
       /* Prepare info block.  */
       grub_memset (vbe_ib, 0, sizeof (*vbe_ib));
@@ -574,7 +574,7 @@ grub_vbe_get_preferred_mode (unsigned int *width, unsigned int *height)
 
   /* Use low memory scratch area as temporary storage for VESA BIOS calls.  */
   flat_panel_info = (struct grub_vbe_flat_panel_info *)
-    (GRUB_MEMORY_MACHINE_SCRATCH_ADDR + sizeof (struct grub_video_edid_info));
+    grub_absolute_pointer (GRUB_MEMORY_MACHINE_SCRATCH_ADDR + sizeof (struct grub_video_edid_info));
 
   if (controller_info.version >= 0x200
       && (grub_vbe_bios_get_ddc_capabilities (&ddc_level) & 0xff)
@@ -676,7 +676,7 @@ grub_vbe_set_video_mode (grub_uint32_t vbe_mode,
 	  == GRUB_VBE_MEMORY_MODEL_PACKED_PIXEL)
 	{
 	  struct grub_vbe_palette_data *palette
-	    = (struct grub_vbe_palette_data *) GRUB_MEMORY_MACHINE_SCRATCH_ADDR;
+	    = (struct grub_vbe_palette_data *) grub_absolute_pointer (GRUB_MEMORY_MACHINE_SCRATCH_ADDR);
 	  unsigned i;
 
 	  /* Make sure that the BIOS can reach the palette.  */
diff --git a/include/grub/compiler.h b/include/grub/compiler.h
index 8f3be3ae70..e159f0e292 100644
--- a/include/grub/compiler.h
+++ b/include/grub/compiler.h
@@ -56,4 +56,15 @@
 #  define CLANG_PREREQ(maj,min) 0
 #endif
 
+#if defined(__GNUC__)
+#  define grub_absolute_pointer(val)					\
+({									\
+	unsigned long __ptr;						\
+	__asm__ ("" : "=r"(__ptr) : "0"((void *)(val)));		\
+	(void *) (__ptr);						\
+})
+#else
+#  define grub_absolute_pointer(val) ((void *)(val))
+#endif
+
 #endif /* ! GRUB_COMPILER_HEADER */
-- 
2.34.1

Places

File 0002-Fix-Werror-array-bounds-array-subscript-0-is-outside.patch of Package grub2 (Revision 421a5cf0a3cd4035b72848e13245b74c)

Places