summaryrefslogtreecommitdiffstats
path: root/arch/x86/mm
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/mm')
-rw-r--r--arch/x86/mm/init.c3
-rw-r--r--arch/x86/mm/init_32.c20
-rw-r--r--arch/x86/mm/init_64.c3
-rw-r--r--arch/x86/mm/pageattr.c5
4 files changed, 27 insertions, 4 deletions
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index c0e28a1..947f42ab 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -364,8 +364,9 @@ void free_init_pages(char *what, unsigned long begin, unsigned long end)
/*
* We just marked the kernel text read only above, now that
* we are going to free part of that, we need to make that
- * writeable first.
+ * writeable and non-executable first.
*/
+ set_memory_nx(begin, (end - begin) >> PAGE_SHIFT);
set_memory_rw(begin, (end - begin) >> PAGE_SHIFT);
printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10);
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 0e969f9..f89b5bb 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -226,7 +226,7 @@ page_table_range_init(unsigned long start, unsigned long end, pgd_t *pgd_base)
static inline int is_kernel_text(unsigned long addr)
{
- if (addr >= PAGE_OFFSET && addr <= (unsigned long)__init_end)
+ if (addr >= (unsigned long)_text && addr <= (unsigned long)__init_end)
return 1;
return 0;
}
@@ -912,6 +912,23 @@ void set_kernel_text_ro(void)
set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT);
}
+static void mark_nxdata_nx(void)
+{
+ /*
+ * When this called, init has already been executed and released,
+ * so everything past _etext sould be NX.
+ */
+ unsigned long start = PFN_ALIGN(_etext);
+ /*
+ * This comes from is_kernel_text upper limit. Also HPAGE where used:
+ */
+ unsigned long size = (((unsigned long)__init_end + HPAGE_SIZE) & HPAGE_MASK) - start;
+
+ if (__supported_pte_mask & _PAGE_NX)
+ printk(KERN_INFO "NX-protecting the kernel data: %luk\n", size >> 10);
+ set_pages_nx(virt_to_page(start), size >> PAGE_SHIFT);
+}
+
void mark_rodata_ro(void)
{
unsigned long start = PFN_ALIGN(_text);
@@ -946,6 +963,7 @@ void mark_rodata_ro(void)
printk(KERN_INFO "Testing CPA: write protecting again\n");
set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT);
#endif
+ mark_nxdata_nx();
}
#endif
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 71a5929..ce59c05 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -788,6 +788,7 @@ void mark_rodata_ro(void)
unsigned long rodata_start =
((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK;
unsigned long end = (unsigned long) &__end_rodata_hpage_align;
+ unsigned long kernel_end = (((unsigned long)&__init_end + HPAGE_SIZE) & HPAGE_MASK);
unsigned long text_end = PAGE_ALIGN((unsigned long) &__stop___ex_table);
unsigned long rodata_end = PAGE_ALIGN((unsigned long) &__end_rodata);
unsigned long data_start = (unsigned long) &_sdata;
@@ -802,7 +803,7 @@ void mark_rodata_ro(void)
* The rodata section (but not the kernel text!) should also be
* not-executable.
*/
- set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT);
+ set_memory_nx(rodata_start, (kernel_end - rodata_start) >> PAGE_SHIFT);
rodata_test();
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 6f2a6b6..8b830ca 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -13,6 +13,7 @@
#include <linux/pfn.h>
#include <linux/percpu.h>
#include <linux/gfp.h>
+#include <linux/pci.h>
#include <asm/e820.h>
#include <asm/processor.h>
@@ -261,8 +262,10 @@ static inline pgprot_t static_protections(pgprot_t prot, unsigned long address,
* The BIOS area between 640k and 1Mb needs to be executable for
* PCI BIOS based config access (CONFIG_PCI_GOBIOS) support.
*/
- if (within(pfn, BIOS_BEGIN >> PAGE_SHIFT, BIOS_END >> PAGE_SHIFT))
+#ifdef CONFIG_PCI_BIOS
+ if (pcibios_enabled && within(pfn, BIOS_BEGIN >> PAGE_SHIFT, BIOS_END >> PAGE_SHIFT))
pgprot_val(forbidden) |= _PAGE_NX;
+#endif
/*
* The kernel text needs to be executable for obvious reasons
OpenPOWER on IntegriCloud