SliTaz Repositories

     1.1 --- a/linux/receipt	Wed Jul 27 13:48:34 2016 +0200
     1.2 +++ b/linux/receipt	Fri Oct 21 16:31:54 2016 +0200
     1.3 @@ -75,6 +75,7 @@
     1.4  003-squashfs-x86-support-xz-compressed-kernel.patch
     1.5  004-squashfs-add-xz-compression-support.patch
     1.6  005-squashfs-add-xz-compression-configuration-option.patch
     1.7 +$PACKAGE-CVE-2016-5195.u
     1.8  EOT
     1.9  
    1.10  	[ ! -x /usr/bin/cook ] && report step "Make kernel proper and then build lguest"

     2.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     2.2 +++ b/linux/stuff/linux-CVE-2016-5195.u	Fri Oct 21 16:31:54 2016 +0200
     2.3 @@ -0,0 +1,84 @@
     2.4 +--- linux-2.6.37/include/linux/mm.h
     2.5 ++++ linux-2.6.37/include/linux/mm.h
     2.6 +@@ -1415,6 +1415,7 @@
     2.7 + #define FOLL_GET	0x04	/* do get_page on page */
     2.8 + #define FOLL_DUMP	0x08	/* give error on hole if it would be zero */
     2.9 + #define FOLL_FORCE	0x10	/* get_user_pages read/write w/o permission */
    2.10 ++#define FOLL_COW	0x4000	/* internal GUP flag */
    2.11 + 
    2.12 + typedef int (*pte_fn_t)(pte_t *pte, pgtable_t token, unsigned long addr,
    2.13 + 			void *data);
    2.14 +--- linux-2.6.37/mm/memory.c
    2.15 ++++ linux-2.6.37/mm/memory.c
    2.16 +@@ -1225,6 +1225,24 @@
    2.17 + }
    2.18 + EXPORT_SYMBOL_GPL(zap_vma_ptes);
    2.19 + 
    2.20 ++static inline bool can_follow_write_pte(pte_t pte, struct page *page,
    2.21 ++					unsigned int flags)
    2.22 ++{
    2.23 ++	if (pte_write(pte))
    2.24 ++		return true;
    2.25 ++
    2.26 ++	/*
    2.27 ++	 * Make sure that we are really following CoWed page. We do not really
    2.28 ++	 * have to care about exclusiveness of the page because we only want
    2.29 ++	 * to ensure that once COWed page hasn't disappeared in the meantime
    2.30 ++	 * or it hasn't been merged to a KSM page.
    2.31 ++	 */
    2.32 ++	if ((flags & FOLL_FORCE) && (flags & FOLL_COW))
    2.33 ++		return page && PageAnon(page) && !PageKsm(page);
    2.34 ++
    2.35 ++	return false;
    2.36 ++}
    2.37 ++
    2.38 + /**
    2.39 +  * follow_page - look up a page descriptor from a user-virtual address
    2.40 +  * @vma: vm_area_struct mapping @address
    2.41 +@@ -1286,10 +1304,13 @@
    2.42 + 	pte = *ptep;
    2.43 + 	if (!pte_present(pte))
    2.44 + 		goto no_page;
    2.45 +-	if ((flags & FOLL_WRITE) && !pte_write(pte))
    2.46 +-		goto unlock;
    2.47 + 
    2.48 + 	page = vm_normal_page(vma, address, pte);
    2.49 ++	if ((flags & FOLL_WRITE) && !can_follow_write_pte(pte, page, flags)) {
    2.50 ++		pte_unmap_unlock(ptep, ptl);
    2.51 ++		return NULL;
    2.52 ++	}
    2.53 ++
    2.54 + 	if (unlikely(!page)) {
    2.55 + 		if ((flags & FOLL_DUMP) ||
    2.56 + 		    !is_zero_pfn(pte_pfn(pte)))
    2.57 +@@ -1310,7 +1331,7 @@
    2.58 + 		 */
    2.59 + 		mark_page_accessed(page);
    2.60 + 	}
    2.61 +-unlock:
    2.62 ++
    2.63 + 	pte_unmap_unlock(ptep, ptl);
    2.64 + out:
    2.65 + 	return page;
    2.66 +@@ -1464,17 +1485,13 @@
    2.67 + 				 * The VM_FAULT_WRITE bit tells us that
    2.68 + 				 * do_wp_page has broken COW when necessary,
    2.69 + 				 * even if maybe_mkwrite decided not to set
    2.70 +-				 * pte_write. We can thus safely do subsequent
    2.71 +-				 * page lookups as if they were reads. But only
    2.72 +-				 * do so when looping for pte_write is futile:
    2.73 +-				 * in some cases userspace may also be wanting
    2.74 +-				 * to write to the gotten user page, which a
    2.75 +-				 * read fault here might prevent (a readonly
    2.76 +-				 * page might get reCOWed by userspace write).
    2.77 ++				 * pte_write. We cannot simply drop FOLL_WRITE
    2.78 ++				 * here because the COWed page might be gone by
    2.79 ++				 * the time we do the subsequent page lookups.
    2.80 + 				 */
    2.81 + 				if ((ret & VM_FAULT_WRITE) &&
    2.82 + 				    !(vma->vm_flags & VM_WRITE))
    2.83 +-					foll_flags &= ~FOLL_WRITE;
    2.84 ++					foll_flags |= FOLL_COW;
    2.85 + 
    2.86 + 				cond_resched();
    2.87 + 			}