From dd7b6847670a84b7bb7c38f8e69b2f12059bca66 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Mon, 25 Jan 2016 12:25:15 -0500 Subject: [PATCH] x86/mm: Honour passed pgprot in track_pfn_insert() and track_pfn_remap() track_pfn_insert() overwrites the pgprot that is passed in with a value based on the VMA's page_prot. This is a problem for people trying to do clever things with the new vm_insert_pfn_prot() as it will simply overwrite the passed protection flags. If we use the current value of the pgprot as the base, then it will behave as people are expecting. Also fix track_pfn_remap() in the same way. Signed-off-by: Matthew Wilcox Acked-by: Andy Lutomirski Cc: Andrew Morton Cc: Andy Lutomirski Cc: Kees Cook Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/1453742717-10326-2-git-send-email-matthew.r.wilcox@intel.com Signed-off-by: Ingo Molnar --- arch/x86/mm/pat.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c index f4ae536b0914..04e2e7144bee 100644 --- a/arch/x86/mm/pat.c +++ b/arch/x86/mm/pat.c @@ -943,7 +943,7 @@ int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot, return -EINVAL; } - *prot = __pgprot((pgprot_val(vma->vm_page_prot) & (~_PAGE_CACHE_MASK)) | + *prot = __pgprot((pgprot_val(*prot) & (~_PAGE_CACHE_MASK)) | cachemode2protval(pcm)); return 0; @@ -959,7 +959,7 @@ int track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot, /* Set prot based on lookup */ pcm = lookup_memtype(pfn_t_to_phys(pfn)); - *prot = __pgprot((pgprot_val(vma->vm_page_prot) & (~_PAGE_CACHE_MASK)) | + *prot = __pgprot((pgprot_val(*prot) & (~_PAGE_CACHE_MASK)) | cachemode2protval(pcm)); return 0; -- GitLab