]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
mm/pagemap: fix wr-protect even if PM_SCAN_WP_MATCHING not set
authorPeter Xu <peterx@redhat.com>
Thu, 16 Nov 2023 20:15:46 +0000 (15:15 -0500)
committerAndrew Morton <akpm@linux-foundation.org>
Thu, 7 Dec 2023 00:12:45 +0000 (16:12 -0800)
commit4980e837cab7e2acc4dad18dba656c6896c531aa
treee07ae75831c0cf96220f9d1ac15a5fcbb160a4f2
parent0dff1b407def32452a0d80148172889862c64fe7
mm/pagemap: fix wr-protect even if PM_SCAN_WP_MATCHING not set

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@redhat.com
Fixes: 12f6b01a0bcb ("fs/proc/task_mmu: add fast paths to get/clear PAGE_IS_WRITTEN flag")
Signed-off-by: Peter Xu <peterx@redhat.com>
Reported-by: syzbot+7ca4b2719dc742b8d0a4@syzkaller.appspotmail.com
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Andrei Vagin <avagin@gmail.com>
Cc: Muhammad Usama Anjum <usama.anjum@collabora.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
fs/proc/task_mmu.c