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mbi: Use per segment a separate relocator chunk

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Instead of setting up a all comprising relocator chunk for all segments,
use per segment a separate relocator chunk.

Currently, if the ELF is non-relocatable, a single relocator chunk will
comprise memory (between the segments) which gets overridden by the relst()
invocation of the movers code in grub_relocator16/32/64_boot().

The overridden memory may contain reserved ranges like VGA memory or ACPI
tables, which may lead to crashes or at least to strange boot behaviour.

Signed-off-by: Alexander Boettcher <alexander.boettcher@genode-labs.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This commit is contained in:
Alexander Boettcher 2018-06-12 20:04:09 +02:00 committed by Daniel Kiper
parent ba474d531a
commit 14ec665c3f
1 changed files with 40 additions and 23 deletions
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63
grub-core/loader/multiboot_elfxx.c
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@ -57,9 +57,9 @@ CONCAT(grub_multiboot_load_elf, XX) (mbi_load_data_t *mld)
char *phdr_base; char *phdr_base;
grub_err_t err; grub_err_t err;
grub_relocator_chunk_t ch; grub_relocator_chunk_t ch;
grub_uint32_t load_offset, load_size; grub_uint32_t load_offset = 0, load_size;
int i; int i;
void *source; void *source = NULL;
if (ehdr->e_ident[EI_MAG0] != ELFMAG0 if (ehdr->e_ident[EI_MAG0] != ELFMAG0
|| ehdr->e_ident[EI_MAG1] != ELFMAG1 || ehdr->e_ident[EI_MAG1] != ELFMAG1
@ -97,10 +97,15 @@ CONCAT(grub_multiboot_load_elf, XX) (mbi_load_data_t *mld)
return grub_error (GRUB_ERR_BAD_OS, "segment crosses 4 GiB border"); return grub_error (GRUB_ERR_BAD_OS, "segment crosses 4 GiB border");
#endif #endif
load_size = highest_load - mld->link_base_addr;
if (mld->relocatable) if (mld->relocatable)
{ {
load_size = highest_load - mld->link_base_addr;
grub_dprintf ("multiboot_loader", "align=0x%lx, preference=0x%x, "
"load_size=0x%x, avoid_efi_boot_services=%d\n",
(long) mld->align, mld->preference, load_size,
mld->avoid_efi_boot_services);
if (load_size > mld->max_addr || mld->min_addr > mld->max_addr - load_size) if (load_size > mld->max_addr || mld->min_addr > mld->max_addr - load_size)
return grub_error (GRUB_ERR_BAD_OS, "invalid min/max address and/or load size"); return grub_error (GRUB_ERR_BAD_OS, "invalid min/max address and/or load size");
@ -108,27 +113,22 @@ CONCAT(grub_multiboot_load_elf, XX) (mbi_load_data_t *mld)
mld->min_addr, mld->max_addr - load_size, mld->min_addr, mld->max_addr - load_size,
load_size, mld->align ? mld->align : 1, load_size, mld->align ? mld->align : 1,
mld->preference, mld->avoid_efi_boot_services); mld->preference, mld->avoid_efi_boot_services);
if (err)
{
grub_dprintf ("multiboot_loader", "Cannot allocate memory for OS image\n");
return err;
}
mld->load_base_addr = get_physical_target_address (ch);
source = get_virtual_current_address (ch);
} }
else else
err = grub_relocator_alloc_chunk_addr (GRUB_MULTIBOOT (relocator), &ch, mld->load_base_addr = mld->link_base_addr;
mld->link_base_addr, load_size);
if (err) grub_dprintf ("multiboot_loader", "relocatable=%d, link_base_addr=0x%x, "
{ "load_base_addr=0x%x\n", relocatable,
grub_dprintf ("multiboot_loader", "Cannot allocate memory for OS image\n"); mld->link_base_addr, mld->load_base_addr);
return err;
}
mld->load_base_addr = get_physical_target_address (ch);
source = get_virtual_current_address (ch);
grub_dprintf ("multiboot_loader", "link_base_addr=0x%x, load_base_addr=0x%x, "
"load_size=0x%x, relocatable=%d\n", mld->link_base_addr,
mld->load_base_addr, load_size, mld->relocatable);
if (mld->relocatable)
grub_dprintf ("multiboot_loader", "align=0x%lx, preference=0x%x, avoid_efi_boot_services=%d\n",
(long) mld->align, mld->preference, mld->avoid_efi_boot_services);
/* Load every loadable segment in memory. */ /* Load every loadable segment in memory. */
for (i = 0; i < ehdr->e_phnum; i++) for (i = 0; i < ehdr->e_phnum; i++)
@ -139,7 +139,24 @@ CONCAT(grub_multiboot_load_elf, XX) (mbi_load_data_t *mld)
grub_dprintf ("multiboot_loader", "segment %d: paddr=0x%lx, memsz=0x%lx, vaddr=0x%lx\n", grub_dprintf ("multiboot_loader", "segment %d: paddr=0x%lx, memsz=0x%lx, vaddr=0x%lx\n",
i, (long) phdr(i)->p_paddr, (long) phdr(i)->p_memsz, (long) phdr(i)->p_vaddr); i, (long) phdr(i)->p_paddr, (long) phdr(i)->p_memsz, (long) phdr(i)->p_vaddr);
load_offset = phdr(i)->p_paddr - mld->link_base_addr; if (mld->relocatable)
{
load_offset = phdr(i)->p_paddr - mld->link_base_addr;
grub_dprintf ("multiboot_loader", "segment %d: load_offset=0x%x\n", i, load_offset);
}
else
{
err = grub_relocator_alloc_chunk_addr (GRUB_MULTIBOOT (relocator), &ch,
phdr(i)->p_paddr, phdr(i)->p_memsz);
if (err)
{
grub_dprintf ("multiboot_loader", "Cannot allocate memory for OS image\n");
return err;
}
source = get_virtual_current_address (ch);
}
if (phdr(i)->p_filesz != 0) if (phdr(i)->p_filesz != 0)
{ {