diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index d0bb522..958ac45 100644 --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -69,7 +69,7 @@ jiffies_64 = jiffies; PHDRS { text PT_LOAD FLAGS(5); /* R_E */ - data PT_LOAD FLAGS(7); /* RWE */ + data PT_LOAD FLAGS(6); /* RW_ */ #ifdef CONFIG_X86_64 user PT_LOAD FLAGS(5); /* R_E */ #ifdef CONFIG_SMP @@ -116,6 +116,10 @@ SECTIONS EXCEPTION_TABLE(16) :text = 0x9090 +#if defined(CONFIG_DEBUG_RODATA) + /* .text should occupy whole number of pages */ + . = ALIGN(PAGE_SIZE); +#endif X64_ALIGN_DEBUG_RODATA_BEGIN RO_DATA(PAGE_SIZE) X64_ALIGN_DEBUG_RODATA_END @@ -307,7 +311,7 @@ SECTIONS __bss_start = .; *(.bss..page_aligned) *(.bss) - . = ALIGN(4); + . = ALIGN(PAGE_SIZE); __bss_stop = .; } diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index b278535..bfacdbe 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -362,8 +362,9 @@ 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 bca7909..85a1a75 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -225,7 +225,7 @@ 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; } @@ -1033,6 +1033,22 @@ 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); @@ -1067,6 +1083,7 @@ 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 ee41bba..0dec7f2 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -761,7 +761,7 @@ void mark_rodata_ro(void) unsigned long start = PFN_ALIGN(_text); unsigned long rodata_start = ((unsigned long)__start_rodata + PAGE_SIZE - 1) & PAGE_MASK; - unsigned long end = (unsigned long) &__end_rodata_hpage_align; + unsigned long 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; diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 91ce756..d130dc5 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -261,8 +261,10 @@ 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. */ +#ifdef CONFIG_PCI_BIOS if (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 diff --git a/arch/x86/pci/pcbios.c b/arch/x86/pci/pcbios.c index 2492d16..34ccb73 100644 --- a/arch/x86/pci/pcbios.c +++ b/arch/x86/pci/pcbios.c @@ -9,6 +9,7 @@ #include #include #include +#include /* BIOS32 signature: "_32_" */ #define BIOS32_SIGNATURE (('_' << 0) + ('3' << 8) + ('2' << 16) + ('_' << 24)) @@ -420,11 +421,24 @@ int pcibios_set_irq_routing(struct pci_dev *dev, int pin, int irq) } EXPORT_SYMBOL(pcibios_set_irq_routing); +/* according some bios specification + * http://members.datafast.net.au/dft0802/specs/bios21.pdf, we could + * restrict the x zone to some pages and make it ro. But we + * really don't care, processor with NX support should be able to use + * mmconfig for pci that disable pcibios... + */ +static inline void set_bios_x(void) +{ + set_memory_x(PAGE_OFFSET + BIOS_BEGIN, (BIOS_END - BIOS_BEGIN) >> PAGE_SHIFT); +} + void __init pci_pcbios_init(void) { - if ((pci_probe & PCI_PROBE_BIOS) - && ((raw_pci_ops = pci_find_bios()))) { - pci_bios_present = 1; + if (pci_probe & PCI_PROBE_BIOS) { + set_bios_x(); + if ((raw_pci_ops = pci_find_bios())) { + pci_bios_present = 1; + } } }