diff options
Diffstat (limited to 'arch/x86/mm')
| -rw-r--r-- | arch/x86/mm/init.c | 3 | ||||
| -rw-r--r-- | arch/x86/mm/init_32.c | 20 | ||||
| -rw-r--r-- | arch/x86/mm/init_64.c | 3 | ||||
| -rw-r--r-- | arch/x86/mm/pageattr.c | 5 |
4 files changed, 27 insertions, 4 deletions
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index c0e28a13de7..947f42abe82 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 0e969f9f401..f89b5bb4e93 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 71a59296af8..ce59c05cae1 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 6f2a6b6deb6..8b830ca14ac 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 |