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2008-09-08 Robert Millan <rmh@aybabtu.com>

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* loader/i386/pc/multiboot.c (grub_multiboot_load_elf32): Skip
        segments when their filesz is zero (grub_file_read() interprets
        zero-size as "read untill EOF", which results in memory corruption).
        Use `lowest_segment' rather than 0 for calculating the current
        segment load address.
This commit is contained in:
robertmh 2008-09-08 19:10:16 +00:00
parent 40da438f10
commit 89d5ffcfd1
2 changed files with 11 additions and 3 deletions
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8
ChangeLog
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@ -1,3 +1,11 @@
2008-09-08 Robert Millan <rmh@aybabtu.com>
* loader/i386/pc/multiboot.c (grub_multiboot_load_elf32): Skip
segments when their filesz is zero (grub_file_read() interprets
zero-size as "read untill EOF", which results in memory corruption).
Use `lowest_segment' rather than 0 for calculating the current
segment load address.
2008-09-08 Robert Millan <rmh@aybabtu.com> 2008-09-08 Robert Millan <rmh@aybabtu.com>
* util/hostdisk.c (open_device): Replace a grub_util_info() call * util/hostdisk.c (open_device): Replace a grub_util_info() call

6
loader/i386/pc/multiboot.c
View file

@ -158,7 +158,7 @@ grub_multiboot_load_elf32 (grub_file_t file, void *buffer)
#define phdr(i) ((Elf32_Phdr *) (phdr_base + (i) * ehdr->e_phentsize)) #define phdr(i) ((Elf32_Phdr *) (phdr_base + (i) * ehdr->e_phentsize))
for (i = 0; i < ehdr->e_phnum; i++) for (i = 0; i < ehdr->e_phnum; i++)
if (phdr(i)->p_type == PT_LOAD) if (phdr(i)->p_type == PT_LOAD && phdr(i)->p_filesz != 0)
{ {
if (phdr(i)->p_paddr < phdr(lowest_segment)->p_paddr) if (phdr(i)->p_paddr < phdr(lowest_segment)->p_paddr)
lowest_segment = i; lowest_segment = i;
@ -177,9 +177,9 @@ grub_multiboot_load_elf32 (grub_file_t file, void *buffer)
/* 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++)
{ {
if (phdr(i)->p_type == PT_LOAD) if (phdr(i)->p_type == PT_LOAD && phdr(i)->p_filesz != 0)
{ {
char *load_this_module_at = (char *) (grub_multiboot_payload_orig + (phdr(i)->p_paddr - phdr(0)->p_paddr)); char *load_this_module_at = (char *) (grub_multiboot_payload_orig + (phdr(i)->p_paddr - phdr(lowest_segment)->p_paddr));
grub_dprintf ("multiboot_loader", "segment %d: paddr=%p, memsz=0x%x\n", grub_dprintf ("multiboot_loader", "segment %d: paddr=%p, memsz=0x%x\n",
i, (void *) phdr(i)->p_paddr, phdr(i)->p_memsz); i, (void *) phdr(i)->p_paddr, phdr(i)->p_memsz);