diff options
| author | Christophe Leroy <christophe.leroy@c-s.fr> | 2018-11-28 20:21:10 +0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2018-12-19 10:56:32 +0300 |
| commit | 385e89d5b20f5a7c33fd7c1904da0e6a8e1b366f (patch) | |
| tree | 6bca1bde5792cd345deca9a6dea1f0b929f42e31 /arch/powerpc/include/asm/book3s | |
| parent | badb9687cec50bdba59746532de1969d6d26f3a7 (diff) | |
| download | linux-385e89d5b20f5a7c33fd7c1904da0e6a8e1b366f.tar.xz | |
powerpc/mm: add exec protection on powerpc 603
The 603 doesn't have a HASH table, TLB misses are handled by
software. It is then possible to generate page fault when
_PAGE_EXEC is not set like in nohash/32.
There is one "reserved" PTE bit available, this patch uses
it for _PAGE_EXEC.
In order to support it, set_pte_filter() and
set_access_flags_filter() are made common, and the handling
is made dependent on MMU_FTR_HPTE_TABLE
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/include/asm/book3s')
| -rw-r--r-- | arch/powerpc/include/asm/book3s/32/hash.h | 1 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/book3s/32/pgtable.h | 18 |
2 files changed, 10 insertions, 9 deletions
diff --git a/arch/powerpc/include/asm/book3s/32/hash.h b/arch/powerpc/include/asm/book3s/32/hash.h index f2892c7ab73e..2a0a467d2985 100644 --- a/arch/powerpc/include/asm/book3s/32/hash.h +++ b/arch/powerpc/include/asm/book3s/32/hash.h @@ -26,6 +26,7 @@ #define _PAGE_WRITETHRU 0x040 /* W: cache write-through */ #define _PAGE_DIRTY 0x080 /* C: page changed */ #define _PAGE_ACCESSED 0x100 /* R: page referenced */ +#define _PAGE_EXEC 0x200 /* software: exec allowed */ #define _PAGE_RW 0x400 /* software: user write access allowed */ #define _PAGE_SPECIAL 0x800 /* software: Special page */ diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h b/arch/powerpc/include/asm/book3s/32/pgtable.h index 727692fd6bca..49d76adb9bc5 100644 --- a/arch/powerpc/include/asm/book3s/32/pgtable.h +++ b/arch/powerpc/include/asm/book3s/32/pgtable.h @@ -10,9 +10,9 @@ /* And here we include common definitions */ #define _PAGE_KERNEL_RO 0 -#define _PAGE_KERNEL_ROX 0 +#define _PAGE_KERNEL_ROX (_PAGE_EXEC) #define _PAGE_KERNEL_RW (_PAGE_DIRTY | _PAGE_RW) -#define _PAGE_KERNEL_RWX (_PAGE_DIRTY | _PAGE_RW) +#define _PAGE_KERNEL_RWX (_PAGE_DIRTY | _PAGE_RW | _PAGE_EXEC) #define _PAGE_HPTEFLAGS _PAGE_HASHPTE @@ -66,11 +66,11 @@ static inline bool pte_user(pte_t pte) */ #define PAGE_NONE __pgprot(_PAGE_BASE) #define PAGE_SHARED __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW) -#define PAGE_SHARED_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW) +#define PAGE_SHARED_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW | _PAGE_EXEC) #define PAGE_COPY __pgprot(_PAGE_BASE | _PAGE_USER) -#define PAGE_COPY_X __pgprot(_PAGE_BASE | _PAGE_USER) +#define PAGE_COPY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC) #define PAGE_READONLY __pgprot(_PAGE_BASE | _PAGE_USER) -#define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_USER) +#define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC) /* Permission masks used for kernel mappings */ #define PAGE_KERNEL __pgprot(_PAGE_BASE | _PAGE_KERNEL_RW) @@ -318,7 +318,7 @@ static inline void __ptep_set_access_flags(struct vm_area_struct *vma, int psize) { unsigned long set = pte_val(entry) & - (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW); + (_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC); pte_update(ptep, 0, set); @@ -371,7 +371,7 @@ 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_special(pte_t pte) { return !!(pte_val(pte) & _PAGE_SPECIAL); } static inline int pte_none(pte_t pte) { return (pte_val(pte) & ~_PTE_NONE_MASK) == 0; } -static inline bool pte_exec(pte_t pte) { return true; } +static inline bool pte_exec(pte_t pte) { return pte_val(pte) & _PAGE_EXEC; } static inline int pte_present(pte_t pte) { @@ -438,7 +438,7 @@ static inline pte_t pte_wrprotect(pte_t pte) static inline pte_t pte_exprotect(pte_t pte) { - return pte; + return __pte(pte_val(pte) & ~_PAGE_EXEC); } static inline pte_t pte_mkclean(pte_t pte) @@ -453,7 +453,7 @@ static inline pte_t pte_mkold(pte_t pte) static inline pte_t pte_mkexec(pte_t pte) { - return pte; + return __pte(pte_val(pte) | _PAGE_EXEC); } static inline pte_t pte_mkpte(pte_t pte) |