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Commit 3372f5a7 authored by Alexander Stein's avatar Alexander Stein Committed by Greg Ungerer
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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: default avatarAlexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: default avatarGreg Ungerer <gerg@uclinux.org>
parent 57e00098

arch/m68k/mm/mcfmmu.c

+5 −4
Original line number Original line Diff line number Diff line
@@ -87,7 +87,7 @@ void __init paging_init(void) 




int cf_tlb_miss(struct pt_regs *regs, int write, int dtlb, int extension_word)

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;

	struct mm_struct *mm;

	pgd_t *pgd;

	pgd_t *pgd;

	pmd_t *pmd;

	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))

	if (!pte_dirty(*pte) && !KMAPAREA(mmuar))

		set_pte(pte, pte_wrprotect(*pte));

		set_pte(pte, pte_wrprotect(*pte));





	mmu_write(MMUTR, (mmuar & PAGE_MASK) | (asid << MMUTR_IDN) |

	mmutr = (mmuar & PAGE_MASK) | (asid << MMUTR_IDN) | MMUTR_V;

		(((int)(pte->pte) & (int)CF_PAGE_MMUTR_MASK)

	if ((mmuar < TASK_UNMAPPED_BASE) || (mmuar >= TASK_SIZE))

		>> CF_PAGE_MMUTR_SHIFT) | MMUTR_V);

		mmutr |= (pte->pte & CF_PAGE_MMUTR_MASK) >> CF_PAGE_MMUTR_SHIFT;

	mmu_write(MMUTR, mmutr);





	mmu_write(MMUDR, (pte_val(*pte) & PAGE_MASK) |

	mmu_write(MMUDR, (pte_val(*pte) & PAGE_MASK) |

		((pte->pte) & CF_PAGE_MMUDR_MASK) | MMUDR_SZ_8KB | MMUDR_X);

		((pte->pte) & CF_PAGE_MMUDR_MASK) | MMUDR_SZ_8KB | MMUDR_X);