[2037] 2009-03-21 Vladimir Serbinenko <[email protected]>

Revision: 2037
          http://svn.sv.gnu.org/viewvc/?view=rev&root=grub&revision=2037
Author:   robertmh
Date:     2009-03-21 23:02:12 +0000 (Sat, 21 Mar 2009)
Log Message:
-----------
2009-03-21  Vladimir Serbinenko  <[email protected]>

        Bugfixes in multiboot for bugs uncovered by solaris kernel.

        * loader/i386/multiboot_elfxx.c (grub_multiboot_load_elf): Corrected
        limit detection.
        Use vaddr of correct segment for entry_point.

Modified Paths:
--------------
    trunk/grub2/ChangeLog
    trunk/grub2/loader/i386/multiboot_elfxx.c

Modified: trunk/grub2/ChangeLog
===================================================================
--- trunk/grub2/ChangeLog	2009-03-21 08:39:59 UTC (rev 2036)
+++ trunk/grub2/ChangeLog	2009-03-21 23:02:12 UTC (rev 2037)
@@ -1,3 +1,11 @@
+2009-03-21  Vladimir Serbinenko  <[email protected]>
+
+	Bugfixes in multiboot for bugs uncovered by solaris kernel.
+
+	* loader/i386/multiboot_elfxx.c (grub_multiboot_load_elf): Corrected
+	limit detection.
+	Use vaddr of correct segment for entry_point.
+
 2009-03-21  Bean  <[email protected]>
 
 	* commands/blocklist.c: Add include file <grub/command.h>, remove

Modified: trunk/grub2/loader/i386/multiboot_elfxx.c
===================================================================
--- trunk/grub2/loader/i386/multiboot_elfxx.c	2009-03-21 08:39:59 UTC (rev 2036)
+++ trunk/grub2/loader/i386/multiboot_elfxx.c	2009-03-21 23:02:12 UTC (rev 2037)
@@ -49,7 +49,7 @@
 {
   Elf_Ehdr *ehdr = (Elf_Ehdr *) buffer;
   char *phdr_base;
-  int lowest_segment = 0, highest_segment = 0;
+  int lowest_segment = -1, highest_segment = -1;
   int i;
 
   if (ehdr->e_ident[EI_CLASS] != ELFCLASSXX)
@@ -83,11 +83,18 @@
   for (i = 0; i < ehdr->e_phnum; i++)
     if (phdr(i)->p_type == PT_LOAD && phdr(i)->p_filesz != 0)
       {
-	if (phdr(i)->p_paddr < phdr(lowest_segment)->p_paddr)
+	/* Beware that segment 0 isn't necessarily loadable */
+	if (lowest_segment == -1 
+	    || phdr(i)->p_paddr < phdr(lowest_segment)->p_paddr)
 	  lowest_segment = i;
-	if (phdr(i)->p_paddr > phdr(highest_segment)->p_paddr)
+	if (highest_segment == -1
+	    || phdr(i)->p_paddr > phdr(highest_segment)->p_paddr)
 	  highest_segment = i;
       }
+
+  if (lowest_segment == -1)
+    return grub_error (GRUB_ERR_BAD_OS, "ELF contains no loadable segments");
+
   code_size = (phdr(highest_segment)->p_paddr + phdr(highest_segment)->p_memsz) - phdr(lowest_segment)->p_paddr;
   grub_multiboot_payload_dest = phdr(lowest_segment)->p_paddr;
 
@@ -105,8 +112,8 @@
         {
 	  char *load_this_module_at = (char *) (grub_multiboot_payload_orig + (long) (phdr(i)->p_paddr - phdr(lowest_segment)->p_paddr));
 
-	  grub_dprintf ("multiboot_loader", "segment %d: paddr=0x%lx, memsz=0x%lx\n",
-			i, (long) phdr(i)->p_paddr, (long) phdr(i)->p_memsz);
+	  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);
 
 	  if (grub_file_seek (file, (grub_off_t) phdr(i)->p_offset)
 	      == (grub_off_t) -1)
@@ -124,8 +131,18 @@
         }
     }
 
-  grub_multiboot_payload_entry_offset = ehdr->e_entry - phdr(lowest_segment)->p_vaddr;
+  for (i = 0; i < ehdr->e_phnum; i++)
+    if (phdr(i)->p_vaddr <= ehdr->e_entry 
+	&& phdr(i)->p_vaddr + phdr(i)->p_memsz > ehdr->e_entry)
+      {
+	grub_multiboot_payload_entry_offset = (ehdr->e_entry - phdr(i)->p_vaddr)
+	  + (phdr(i)->p_paddr  - phdr(lowest_segment)->p_paddr);
+	break;
+      }
 
+  if (i == ehdr->e_phnum)
+    return grub_error (GRUB_ERR_BAD_OS, "entry point isn't in a segment");
+
 #undef phdr
 
   return grub_errno;