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| author | Will Deacon <will.deacon@arm.com> | 2013-01-09 11:08:10 +0000 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2013-01-10 10:43:44 +0000 |
| commit | 02522463c84748b3b8ad770f9424bcfa70a5b4c4 (patch) | |
| tree | 5fc357a4979da3d355735215a01900b3f2e2994c /arch/arm64 | |
| parent | bdba0051ebcb3c6372f9cc0b2524c47cc6ce46fd (diff) | |
| download | linux-02522463c84748b3b8ad770f9424bcfa70a5b4c4.tar.bz2 | |
arm64: mm: only wrprotect clean ptes if they are present
Marking non-present ptes as read-only can corrupt file ptes, breaking
things like swap and file mappings.
This patch ensures that we only manipulate user pte bits when the pte
is marked present.
Cc: <stable@vger.kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64')
| -rw-r--r-- | arch/arm64/include/asm/pgtable.h | 16 |
1 files changed, 9 insertions, 7 deletions
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 64b133949502..7adf4142a85c 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -132,9 +132,8 @@ extern struct page *empty_zero_page; #define pte_write(pte) (!(pte_val(pte) & PTE_RDONLY)) #define pte_exec(pte) (!(pte_val(pte) & PTE_UXN)) -#define pte_present_exec_user(pte) \ - ((pte_val(pte) & (PTE_VALID | PTE_USER | PTE_UXN)) == \ - (PTE_VALID | PTE_USER)) +#define pte_present_user(pte) \ + ((pte_val(pte) & (PTE_VALID | PTE_USER)) == (PTE_VALID | PTE_USER)) #define PTE_BIT_FUNC(fn,op) \ static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; } @@ -157,10 +156,13 @@ extern void __sync_icache_dcache(pte_t pteval, unsigned long addr); static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pte) { - if (pte_present_exec_user(pte)) - __sync_icache_dcache(pte, addr); - if (!pte_dirty(pte)) - pte = pte_wrprotect(pte); + if (pte_present_user(pte)) { + if (pte_exec(pte)) + __sync_icache_dcache(pte, addr); + if (!pte_dirty(pte)) + pte = pte_wrprotect(pte); + } + set_pte(ptep, pte); } |