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| author | Alexander Stein <alexander.stein@systec-electronic.com> | 2012-01-23 15:45:56 +0100 |
|---|---|---|
| committer | Greg Ungerer <gerg@uclinux.org> | 2012-02-07 02:25:57 +0100 |
| commit | 3372f5a7d005dd42e754490fed6a0171c4a018c6 (patch) | |
| tree | 8f3bba690f3c674383e9c30ea14a087c44a95dec /arch/m68k | |
| parent | m68k: Add shared bit to Coldfire kernel page entries (diff) | |
| download | linux-3372f5a7d005dd42e754490fed6a0171c4a018c6.tar.xz linux-3372f5a7d005dd42e754490fed6a0171c4a018c6.zip | |
m68k: Do not set global share for non-kernel shared pages
If the SG bit is set in MMUTR the page is accessible for all
userspace processes (ignoring the ASID). So a process might randomly
access a page from a different process which had a shared page
(from shared memory) in its context.
Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Diffstat (limited to 'arch/m68k')
| -rw-r--r-- | arch/m68k/mm/mcfmmu.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/arch/m68k/mm/mcfmmu.c b/arch/m68k/mm/mcfmmu.c index babd5a97cdcb..875b800ef0dd 100644 --- a/arch/m68k/mm/mcfmmu.c +++ b/arch/m68k/mm/mcfmmu.c @@ -87,7 +87,7 @@ void __init paging_init(void) int cf_tlb_miss(struct pt_regs *regs, int write, int dtlb, int extension_word) { - unsigned long flags, mmuar; + unsigned long flags, mmuar, mmutr; struct mm_struct *mm; pgd_t *pgd; pmd_t *pmd; @@ -137,9 +137,10 @@ int cf_tlb_miss(struct pt_regs *regs, int write, int dtlb, int extension_word) if (!pte_dirty(*pte) && !KMAPAREA(mmuar)) set_pte(pte, pte_wrprotect(*pte)); - mmu_write(MMUTR, (mmuar & PAGE_MASK) | (asid << MMUTR_IDN) | - (((int)(pte->pte) & (int)CF_PAGE_MMUTR_MASK) - >> CF_PAGE_MMUTR_SHIFT) | MMUTR_V); + mmutr = (mmuar & PAGE_MASK) | (asid << MMUTR_IDN) | MMUTR_V; + if ((mmuar < TASK_UNMAPPED_BASE) || (mmuar >= TASK_SIZE)) + mmutr |= (pte->pte & CF_PAGE_MMUTR_MASK) >> CF_PAGE_MMUTR_SHIFT; + mmu_write(MMUTR, mmutr); mmu_write(MMUDR, (pte_val(*pte) & PAGE_MASK) | ((pte->pte) & CF_PAGE_MMUDR_MASK) | MMUDR_SZ_8KB | MMUDR_X); |