diff options
| author | Andi Kleen <ak@suse.de> | 2006-09-26 10:52:37 +0200 |
|---|---|---|
| committer | Andi Kleen <andi@basil.nowhere.org> | 2006-09-26 10:52:37 +0200 |
| commit | df992848f5aa803fcacd2c5e7d67034bb89e3fa3 (patch) | |
| tree | 649ee5888f71bdd4243599f73d9725118262d368 | |
| parent | d3cf7f061521c78ad62e275eb6fbdc8f43fc75a7 (diff) | |
[PATCH] Fix pte_exec/mkexec and use it in change_page_attr()
Fix the pte_exec/mkexec page table accessor functions to really
use the NX bit. Previously they only checked the USER bit, but
weren't actually used for anything.
Then use them in change_page_attr() to manipulate the NX bit
properly.
Signed-off-by: Andi Kleen <ak@suse.de>
| -rw-r--r-- | arch/x86_64/mm/pageattr.c | 8 | ||||
| -rw-r--r-- | include/asm-x86_64/pgtable.h | 4 |
2 files changed, 7 insertions, 5 deletions
diff --git a/arch/x86_64/mm/pageattr.c b/arch/x86_64/mm/pageattr.c index 2685b1f3671..01591b649f4 100644 --- a/arch/x86_64/mm/pageattr.c +++ b/arch/x86_64/mm/pageattr.c @@ -190,10 +190,12 @@ int change_page_attr_addr(unsigned long address, int numpages, pgprot_t prot) * lowmem */ if (__pa(address) < KERNEL_TEXT_SIZE) { unsigned long addr2; - pgprot_t prot2 = prot; + pgprot_t prot2; addr2 = __START_KERNEL_map + __pa(address); - pgprot_val(prot2) &= ~_PAGE_NX; - err = __change_page_attr(addr2, pfn, prot2, PAGE_KERNEL_EXEC); + /* Make sure the kernel mappings stay executable */ + prot2 = pte_pgprot(pte_mkexec(pfn_pte(0, prot))); + err = __change_page_attr(addr2, pfn, prot2, + PAGE_KERNEL_EXEC); } } up_write(&init_mm.mmap_sem); diff --git a/include/asm-x86_64/pgtable.h b/include/asm-x86_64/pgtable.h index d79e7441b51..f7614670c65 100644 --- a/include/asm-x86_64/pgtable.h +++ b/include/asm-x86_64/pgtable.h @@ -265,7 +265,7 @@ static inline pte_t pfn_pte(unsigned long page_nr, pgprot_t pgprot) #define __LARGE_PTE (_PAGE_PSE|_PAGE_PRESENT) static inline int pte_user(pte_t pte) { return pte_val(pte) & _PAGE_USER; } static inline int pte_read(pte_t pte) { return pte_val(pte) & _PAGE_USER; } -static inline int pte_exec(pte_t pte) { return pte_val(pte) & _PAGE_USER; } +static inline int pte_exec(pte_t pte) { return !(pte_val(pte) & _PAGE_NX); } static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_DIRTY; } static inline int pte_young(pte_t pte) { return pte_val(pte) & _PAGE_ACCESSED; } static inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_RW; } @@ -278,7 +278,7 @@ static inline pte_t pte_mkclean(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) & static inline pte_t pte_mkold(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_ACCESSED)); return pte; } static inline pte_t pte_wrprotect(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_RW)); return pte; } static inline pte_t pte_mkread(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_USER)); return pte; } -static inline pte_t pte_mkexec(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_USER)); return pte; } +static inline pte_t pte_mkexec(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_NX)); return pte; } static inline pte_t pte_mkdirty(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_DIRTY)); return pte; } static inline pte_t pte_mkyoung(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_ACCESSED)); return pte; } static inline pte_t pte_mkwrite(pte_t pte) { set_pte(&pte, __pte(pte_val(pte) | _PAGE_RW)); return pte; } |