lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Tue, 17 Mar 2015 09:41:09 +0100 From: Jiri Slaby <jslaby@...e.cz> To: stable@...r.kernel.org Cc: linux-kernel@...r.kernel.org, Naoya Horiguchi <n-horiguchi@...jp.nec.com>, Hugh Dickins <hughd@...gle.com>, James Hogan <james.hogan@...tec.com>, David Rientjes <rientjes@...gle.com>, Mel Gorman <mel@....ul.ie>, Johannes Weiner <hannes@...xchg.org>, Michal Hocko <mhocko@...e.cz>, Rik van Riel <riel@...hat.com>, Andrea Arcangeli <aarcange@...hat.com>, Luiz Capitulino <lcapitulino@...hat.com>, Nishanth Aravamudan <nacc@...ux.vnet.ibm.com>, Lee Schermerhorn <lee.schermerhorn@...com>, Steve Capper <steve.capper@...aro.org>, Andrew Morton <akpm@...ux-foundation.org>, Linus Torvalds <torvalds@...ux-foundation.org>, Jiri Slaby <jslaby@...e.cz> Subject: [PATCH 3.12 091/175] mm/hugetlb: add migration/hwpoisoned entry check in hugetlb_change_protection From: Naoya Horiguchi <n-horiguchi@...jp.nec.com> 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit a8bda28d87c38c6aa93de28ba5d30cc18e865a11 upstream. There is a race condition between hugepage migration and change_protection(), where hugetlb_change_protection() doesn't care about migration entries and wrongly overwrites them. That causes unexpected results like kernel crash. HWPoison entries also can cause the same problem. This patch adds is_hugetlb_entry_(migration|hwpoisoned) check in this function to do proper actions. Fixes: 290408d4a2 ("hugetlb: hugepage migration core") Signed-off-by: Naoya Horiguchi <n-horiguchi@...jp.nec.com> Cc: Hugh Dickins <hughd@...gle.com> Cc: James Hogan <james.hogan@...tec.com> Cc: David Rientjes <rientjes@...gle.com> Cc: Mel Gorman <mel@....ul.ie> Cc: Johannes Weiner <hannes@...xchg.org> Cc: Michal Hocko <mhocko@...e.cz> Cc: Rik van Riel <riel@...hat.com> Cc: Andrea Arcangeli <aarcange@...hat.com> Cc: Luiz Capitulino <lcapitulino@...hat.com> Cc: Nishanth Aravamudan <nacc@...ux.vnet.ibm.com> Cc: Lee Schermerhorn <lee.schermerhorn@...com> Cc: Steve Capper <steve.capper@...aro.org> Signed-off-by: Andrew Morton <akpm@...ux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@...ux-foundation.org> Signed-off-by: Jiri Slaby <jslaby@...e.cz> --- mm/hugetlb.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 0b46aedef779..723e63aefb64 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -3175,7 +3175,24 @@ unsigned long hugetlb_change_protection(struct vm_area_struct *vma, pages++; continue; } - if (!huge_pte_none(huge_ptep_get(ptep))) { + pte = huge_ptep_get(ptep); + if (unlikely(is_hugetlb_entry_hwpoisoned(pte))) { + continue; + } + if (unlikely(is_hugetlb_entry_migration(pte))) { + swp_entry_t entry = pte_to_swp_entry(pte); + + if (is_write_migration_entry(entry)) { + pte_t newpte; + + make_migration_entry_read(&entry); + newpte = swp_entry_to_pte(entry); + set_huge_pte_at(mm, address, ptep, newpte); + pages++; + } + continue; + } + if (!huge_pte_none(pte)) { pte = huge_ptep_get_and_clear(mm, address, ptep); pte = pte_mkhuge(huge_pte_modify(pte, newprot)); pte = arch_make_huge_pte(pte, vma, NULL, 0); -- 2.3.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists