4.14-stable patches

added patches:
	migrate-hugetlb-check-for-hugetlb-shared-pmd-in-node-migration.patch

diff --git a/queue-4.14/migrate-hugetlb-check-for-hugetlb-shared-pmd-in-node-migration.patch b/queue-4.14/migrate-hugetlb-check-for-hugetlb-shared-pmd-in-node-migration.patch
new file mode 100644 (file)
index 0000000..60511b4
--- /dev/null
+++ b/queue-4.14/migrate-hugetlb-check-for-hugetlb-shared-pmd-in-node-migration.patch
@@ -0,0 +1,50 @@
+From 73bdf65ea74857d7fb2ec3067a3cec0e261b1462 Mon Sep 17 00:00:00 2001
+From: Mike Kravetz <mike.kravetz@oracle.com>
+Date: Thu, 26 Jan 2023 14:27:21 -0800
+Subject: migrate: hugetlb: check for hugetlb shared PMD in node migration
+
+From: Mike Kravetz <mike.kravetz@oracle.com>
+
+commit 73bdf65ea74857d7fb2ec3067a3cec0e261b1462 upstream.
+
+migrate_pages/mempolicy semantics state that CAP_SYS_NICE is required to
+move pages shared with another process to a different node.  page_mapcount
+> 1 is being used to determine if a hugetlb page is shared.  However, a
+hugetlb page will have a mapcount of 1 if mapped by multiple processes via
+a shared PMD.  As a result, hugetlb pages shared by multiple processes and
+mapped with a shared PMD can be moved by a process without CAP_SYS_NICE.
+
+To fix, check for a shared PMD if mapcount is 1.  If a shared PMD is found
+consider the page shared.
+
+Link: https://lkml.kernel.org/r/20230126222721.222195-3-mike.kravetz@oracle.com
+Fixes: e2d8cf405525 ("migrate: add hugepage migration code to migrate_pages()")
+Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
+Acked-by: Peter Xu <peterx@redhat.com>
+Acked-by: David Hildenbrand <david@redhat.com>
+Cc: James Houghton <jthoughton@google.com>
+Cc: Matthew Wilcox <willy@infradead.org>
+Cc: Michal Hocko <mhocko@suse.com>
+Cc: Muchun Song <songmuchun@bytedance.com>
+Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
+Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com>
+Cc: Yang Shi <shy828301@gmail.com>
+Cc: <stable@vger.kernel.org>
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ mm/mempolicy.c |    3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+--- a/mm/mempolicy.c
++++ b/mm/mempolicy.c
+@@ -574,7 +574,8 @@ static int queue_pages_hugetlb(pte_t *pt
+               goto unlock;
+       /* With MPOL_MF_MOVE, we migrate only unshared hugepage. */
+       if (flags & (MPOL_MF_MOVE_ALL) ||
+-          (flags & MPOL_MF_MOVE && page_mapcount(page) == 1))
++          (flags & MPOL_MF_MOVE && page_mapcount(page) == 1 &&
++           !hugetlb_pmd_shared(pte)))
+               isolate_huge_page(page, qp->pagelist);
+ unlock:
+       spin_unlock(ptl);

diff --git a/queue-4.14/series b/queue-4.14/series
index 3460f36130e748754eabcf872c471d940adf5dfe..27f4e84fa1445acd7fdc4f570f848115cfb37160 100644 (file)
--- a/queue-4.14/series
+++ b/queue-4.14/series
@@ -30,3 +30,4 @@ pinctrl-aspeed-fix-confusing-types-in-return-value.patch
 pinctrl-single-fix-potential-null-dereference.patch
 net-usb-fix-wrong-direction-warning-in-plusb.c.patch
 usb-core-add-quirk-for-alcor-link-ak9563-smartcard-reader.patch
+migrate-hugetlb-check-for-hugetlb-shared-pmd-in-node-migration.patch