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|
--- binutils-2.17.50.0.7/bfd/elf-bfd.h
+++ binutils-2.17.50.0.7/bfd/elf-bfd.h
@@ -1348,6 +1348,9 @@ struct elf_obj_tdata
/* Should the PT_GNU_RELRO segment be emitted? */
bfd_boolean relro;
+ /* Segment flags for the PT_PAX_FLAGS segment. */
+ unsigned int pax_flags;
+
/* Symbol version definitions in external objects. */
Elf_Internal_Verdef *verdef;
--- binutils-2.17.50.0.7/bfd/elf.c
+++ binutils-2.17.50.0.7/bfd/elf.c
@@ -1109,6 +1109,7 @@ get_segment_type (unsigned int p_type)
case PT_GNU_EH_FRAME: pt = "EH_FRAME"; break;
case PT_GNU_STACK: pt = "STACK"; break;
case PT_GNU_RELRO: pt = "RELRO"; break;
+ case PT_PAX_FLAGS: pt = "PAX_FLAGS"; break;
default: pt = NULL; break;
}
return pt;
@@ -2679,6 +2680,9 @@ bfd_section_from_phdr (bfd *abfd, Elf_In
case PT_GNU_RELRO:
return _bfd_elf_make_section_from_phdr (abfd, hdr, index, "relro");
+ case PT_PAX_FLAGS:
+ return _bfd_elf_make_section_from_phdr (abfd, hdr, index, "pax_flags");
+
default:
/* Check for any processor-specific program segment types. */
bed = get_elf_backend_data (abfd);
@@ -3633,6 +3637,11 @@ get_program_header_size (bfd *abfd, stru
++segs;
}
+ {
+ /* We need a PT_PAX_FLAGS segment. */
+ ++segs;
+ }
+
for (s = abfd->sections; s != NULL; s = s->next)
{
if ((s->flags & SEC_LOAD) != 0
@@ -4116,6 +4125,20 @@ _bfd_elf_map_sections_to_segments (bfd *
pm = &m->next;
}
+ {
+ amt = sizeof (struct elf_segment_map);
+ m = bfd_zalloc (abfd, amt);
+ if (m == NULL)
+ goto error_return;
+ m->next = NULL;
+ m->p_type = PT_PAX_FLAGS;
+ m->p_flags = elf_tdata (abfd)->pax_flags;
+ m->p_flags_valid = 1;
+
+ *pm = m;
+ pm = &m->next;
+ }
+
free (sections);
elf_tdata (abfd)->segment_map = mfirst;
}
@@ -5229,7 +5252,8 @@ rewrite_elf_program_header (bfd *ibfd, b
6. PT_TLS segment includes only SHF_TLS sections.
7. SHF_TLS sections are only in PT_TLS or PT_LOAD segments.
8. PT_DYNAMIC should not contain empty sections at the beginning
- (with the possible exception of .dynamic). */
+ (with the possible exception of .dynamic).
+ 9. PT_PAX_FLAGS segments does not include any sections. */
#define IS_SECTION_IN_INPUT_SEGMENT(section, segment, bed) \
((((segment->p_paddr \
? IS_CONTAINED_BY_LMA (section, segment, segment->p_paddr) \
@@ -5238,6 +5262,7 @@ rewrite_elf_program_header (bfd *ibfd, b
&& (section->flags & SEC_ALLOC) != 0) \
|| IS_COREFILE_NOTE (segment, section)) \
&& segment->p_type != PT_GNU_STACK \
+ && segment->p_type != PT_PAX_FLAGS \
&& (segment->p_type != PT_TLS \
|| (section->flags & SEC_THREAD_LOCAL)) \
&& (segment->p_type == PT_LOAD \
--- binutils-2.17.50.0.7/bfd/elflink.c
+++ binutils-2.17.50.0.7/bfd/elflink.c
@@ -5229,17 +5229,31 @@ bfd_elf_size_dynamic_sections (bfd *outp
if (!is_elf_hash_table (info->hash))
return TRUE;
+ elf_tdata (output_bfd)->pax_flags = PF_NORANDEXEC;
+
+ if (info->execheap)
+ elf_tdata (output_bfd)->pax_flags |= PF_NOMPROTECT;
+ else if (info->noexecheap)
+ elf_tdata (output_bfd)->pax_flags |= PF_MPROTECT;
+
elf_tdata (output_bfd)->relro = info->relro;
if (info->execstack)
- elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | PF_X;
+ {
+ elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | PF_X;
+ elf_tdata (output_bfd)->pax_flags |= PF_EMUTRAMP;
+ }
else if (info->noexecstack)
- elf_tdata (output_bfd)->stack_flags = PF_R | PF_W;
+ {
+ elf_tdata (output_bfd)->stack_flags = PF_R | PF_W;
+ elf_tdata (output_bfd)->pax_flags |= PF_NOEMUTRAMP;
+ }
else
{
bfd *inputobj;
asection *notesec = NULL;
int exec = 0;
+ elf_tdata (output_bfd)->pax_flags |= PF_NOEMUTRAMP;
for (inputobj = info->input_bfds;
inputobj;
inputobj = inputobj->link_next)
@@ -5252,7 +5266,11 @@ bfd_elf_size_dynamic_sections (bfd *outp
if (s)
{
if (s->flags & SEC_CODE)
- exec = PF_X;
+ {
+ elf_tdata (output_bfd)->pax_flags &= ~PF_NOEMUTRAMP;
+ elf_tdata (output_bfd)->pax_flags |= PF_EMUTRAMP;
+ exec = PF_X;
+ }
notesec = s;
}
else
--- binutils-2.17.50.0.7/binutils/readelf.c
+++ binutils-2.17.50.0.7/binutils/readelf.c
@@ -2437,6 +2437,7 @@ get_segment_type (unsigned long p_type)
return "GNU_EH_FRAME";
case PT_GNU_STACK: return "GNU_STACK";
case PT_GNU_RELRO: return "GNU_RELRO";
+ case PT_PAX_FLAGS: return "PAX_FLAGS";
default:
if ((p_type >= PT_LOPROC) && (p_type <= PT_HIPROC))
--- binutils-2.17.50.0.7/include/bfdlink.h
+++ binutils-2.17.50.0.7/include/bfdlink.h
@@ -320,6 +320,14 @@ struct bfd_link_info
/* TRUE if PT_GNU_RELRO segment should be created. */
unsigned int relro: 1;
+ /* TRUE if PT_PAX_FLAGS segment should be created with PF_NOMPROTECT
+ flags. */
+ unsigned int execheap: 1;
+
+ /* TRUE if PT_PAX_FLAGS segment should be created with PF_MPROTECT
+ flags. */
+ unsigned int noexecheap: 1;
+
/* TRUE if we should warn when adding a DT_TEXTREL to a shared object. */
unsigned int warn_shared_textrel: 1;
--- binutils-2.17.50.0.7/include/elf/common.h
+++ binutils-2.17.50.0.7/include/elf/common.h
@@ -306,12 +306,29 @@
#define PT_SUNW_EH_FRAME PT_GNU_EH_FRAME /* Solaris uses the same value */
#define PT_GNU_STACK (PT_LOOS + 0x474e551) /* Stack flags */
#define PT_GNU_RELRO (PT_LOOS + 0x474e552) /* Read-only after relocation */
+#define PT_PAX_FLAGS (PT_LOOS + 0x5041580) /* PaX flags */
/* Program segment permissions, in program header p_flags field. */
#define PF_X (1 << 0) /* Segment is executable */
#define PF_W (1 << 1) /* Segment is writable */
#define PF_R (1 << 2) /* Segment is readable */
+
+/* Flags to control PaX behavior. */
+
+#define PF_PAGEEXEC (1 << 4) /* Enable PAGEEXEC */
+#define PF_NOPAGEEXEC (1 << 5) /* Disable PAGEEXEC */
+#define PF_SEGMEXEC (1 << 6) /* Enable SEGMEXEC */
+#define PF_NOSEGMEXEC (1 << 7) /* Disable SEGMEXEC */
+#define PF_MPROTECT (1 << 8) /* Enable MPROTECT */
+#define PF_NOMPROTECT (1 << 9) /* Disable MPROTECT */
+#define PF_RANDEXEC (1 << 10) /* Enable RANDEXEC */
+#define PF_NORANDEXEC (1 << 11) /* Disable RANDEXEC */
+#define PF_EMUTRAMP (1 << 12) /* Enable EMUTRAMP */
+#define PF_NOEMUTRAMP (1 << 13) /* Disable EMUTRAMP */
+#define PF_RANDMMAP (1 << 14) /* Enable RANDMMAP */
+#define PF_NORANDMMAP (1 << 15) /* Disable RANDMMAP */
+
/* #define PF_MASKOS 0x0F000000 *//* OS-specific reserved bits */
#define PF_MASKOS 0x0FF00000 /* New value, Oct 4, 1999 Draft */
#define PF_MASKPROC 0xF0000000 /* Processor-specific reserved bits */
--- binutils-2.17.50.0.7/ld/emultempl/elf32.em
+++ binutils-2.17.50.0.7/ld/emultempl/elf32.em
@@ -1862,6 +1862,16 @@ cat >>e${EMULATION_NAME}.c <<EOF
link_info.noexecstack = TRUE;
link_info.execstack = FALSE;
}
+ else if (strcmp (optarg, "execheap") == 0)
+ {
+ link_info.execheap = TRUE;
+ link_info.noexecheap = FALSE;
+ }
+ else if (strcmp (optarg, "noexecheap") == 0)
+ {
+ link_info.noexecheap = TRUE;
+ link_info.execheap = FALSE;
+ }
EOF
if test -n "$COMMONPAGESIZE"; then
@@ -1928,6 +1938,7 @@ cat >>e${EMULATION_NAME}.c <<EOF
fprintf (file, _(" -z combreloc\t\tMerge dynamic relocs into one section and sort\n"));
fprintf (file, _(" -z defs\t\tReport unresolved symbols in object files.\n"));
fprintf (file, _(" -z execstack\t\tMark executable as requiring executable stack\n"));
+ fprintf (file, _(" -z execheap\t\tMark executable as requiring executable heap\n"));
fprintf (file, _(" -z initfirst\t\tMark DSO to be initialized first at runtime\n"));
fprintf (file, _(" -z interpose\t\tMark object to interpose all DSOs but executable\n"));
fprintf (file, _(" -z lazy\t\tMark object lazy runtime binding (default)\n"));
@@ -1940,6 +1951,7 @@ cat >>e${EMULATION_NAME}.c <<EOF
fprintf (file, _(" -z nodlopen\t\tMark DSO not available to dlopen\n"));
fprintf (file, _(" -z nodump\t\tMark DSO not available to dldump\n"));
fprintf (file, _(" -z noexecstack\tMark executable as not requiring executable stack\n"));
+ fprintf (file, _(" -z noexecheap\tMark executable as not requiring executable heap\n"));
EOF
if test -n "$COMMONPAGESIZE"; then
--- binutils-2.17.50.0.7/ld/ldgram.y
+++ binutils-2.17.50.0.7/ld/ldgram.y
@@ -1094,6 +1094,8 @@ phdr_type:
$$ = exp_intop (0x6474e550);
else if (strcmp (s, "PT_GNU_STACK") == 0)
$$ = exp_intop (0x6474e551);
+ else if (strcmp (s, "PT_PAX_FLAGS") == 0)
+ $$ = exp_intop (0x65041580);
else
{
einfo (_("\
|
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