diff options
| -rw-r--r-- | arch/x86/include/asm/pci.h | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/vmlinux.lds.S | 8 | ||||
| -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 | ||||
| -rw-r--r-- | arch/x86/pci/pcbios.c | 23 |
7 files changed, 57 insertions, 6 deletions
diff --git a/arch/x86/include/asm/pci.h b/arch/x86/include/asm/pci.h index ca0437c..6761292 100644 --- a/arch/x86/include/asm/pci.h +++ b/arch/x86/include/asm/pci.h @@ -65,6 +65,7 @@ extern unsigned long pci_mem_start; #define PCIBIOS_MIN_CARDBUS_IO 0x4000 +extern int pcibios_enabled; void pcibios_config_init(void); struct pci_bus *pcibios_scan_root(int bus); diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index e03530a..bf47007 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 @@ -335,7 +339,7 @@ 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 c0e28a1..947f42a 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 diff --git a/arch/x86/pci/pcbios.c b/arch/x86/pci/pcbios.c index 2492d16..a5f7d0d 100644 --- a/arch/x86/pci/pcbios.c +++ b/arch/x86/pci/pcbios.c @@ -9,6 +9,7 @@ #include <linux/uaccess.h> #include <asm/pci_x86.h> #include <asm/pci-functions.h> +#include <asm/cacheflush.h> /* BIOS32 signature: "_32_" */ #define BIOS32_SIGNATURE (('_' << 0) + ('3' << 8) + ('2' << 16) + ('_' << 24)) @@ -25,6 +26,27 @@ #define PCIBIOS_HW_TYPE1_SPEC 0x10 #define PCIBIOS_HW_TYPE2_SPEC 0x20 +int pcibios_enabled; + +/* According to the BIOS specification at: + * http://members.datafast.net.au/dft0802/specs/bios21.pdf, we could + * restrict the x zone to some pages and make it ro. But this may be + * broken on some bios, complex to handle with static_protections. + * We could make the 0xe0000-0x100000 range rox, but this can break + * some ISA mapping. + * + * So we let's an rw and x hole when pcibios is used. This shouldn't + * happen for modern system with mmconfig, and if you don't want it + * you could disable pcibios... + */ +static inline void set_bios_x(void) +{ + pcibios_enabled = 1; + set_memory_x(PAGE_OFFSET + BIOS_BEGIN, (BIOS_END - BIOS_BEGIN) >> PAGE_SHIFT); + if (__supported_pte_mask & _PAGE_NX) + printk(KERN_INFO "PCI : PCI BIOS aera is rw and x. Use pci=nobios if you want it NX.\n"); +} + /* * This is the standard structure used to identify the entry point * to the BIOS32 Service Directory, as documented in @@ -332,6 +354,7 @@ static struct pci_raw_ops * __devinit pci_find_bios(void) DBG("PCI: BIOS32 Service Directory entry at 0x%lx\n", bios32_entry); bios32_indirect.address = bios32_entry + PAGE_OFFSET; + set_bios_x(); if (check_pcibios()) return &pci_bios_access; } |