[merged mm-hotfixes-stable] mm-pagemap-fix-wr-protect-even-if-pm_scan_wp_matching-not-set.patch removed from -mm tree

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



The quilt patch titled
     Subject: mm/pagemap: fix wr-protect even if PM_SCAN_WP_MATCHING not set
has been removed from the -mm tree.  Its filename was
     mm-pagemap-fix-wr-protect-even-if-pm_scan_wp_matching-not-set.patch

This patch was dropped because it was merged into the mm-hotfixes-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: Peter Xu <peterx@xxxxxxxxxx>
Subject: mm/pagemap: fix wr-protect even if PM_SCAN_WP_MATCHING not set
Date: Thu, 16 Nov 2023 15:15:46 -0500

The new pagemap ioctl contains a fast path for wr-protections without
looking into category masks.  It forgets to check PM_SCAN_WP_MATCHING
before applying the wr-protections.  It can cause, e.g., pte markers
installed on archs that do not even support uffd wr-protect.

WARNING: CPU: 0 PID: 5059 at mm/memory.c:1520 zap_pte_range mm/memory.c:1520 [inline]

Link: https://lkml.kernel.org/r/20231116201547.536857-3-peterx@xxxxxxxxxx
Fixes: 12f6b01a0bcb ("fs/proc/task_mmu: add fast paths to get/clear PAGE_IS_WRITTEN flag")
Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
Reported-by: syzbot+7ca4b2719dc742b8d0a4@xxxxxxxxxxxxxxxxxxxxxxxxx
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
Reviewed-by: Andrei Vagin <avagin@xxxxxxxxx>
Cc: Muhammad Usama Anjum <usama.anjum@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

 fs/proc/task_mmu.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/proc/task_mmu.c~mm-pagemap-fix-wr-protect-even-if-pm_scan_wp_matching-not-set
+++ a/fs/proc/task_mmu.c
@@ -2156,7 +2156,7 @@ static int pagemap_scan_pmd_entry(pmd_t
 		return 0;
 	}
 
-	if (!p->vec_out) {
+	if ((p->arg.flags & PM_SCAN_WP_MATCHING) && !p->vec_out) {
 		/* Fast path for performing exclusive WP */
 		for (addr = start; addr != end; pte++, addr += PAGE_SIZE) {
 			if (pte_uffd_wp(ptep_get(pte)))
_

Patches currently in -mm which might be from peterx@xxxxxxxxxx are

fs-kconfig-make-hugetlbfs-a-menuconfig.patch
mm-gup-fix-follow_devmap_pd-on-page==null-handling.patch




[Index of Archives]     [Kernel Archive]     [IETF Annouce]     [DCCP]     [Netdev]     [Networking]     [Security]     [Bugtraq]     [Yosemite]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux SCSI]

  Powered by Linux