+ mmap-fix-remap_file_pages-regression.patch added to mm-hotfixes-unstable branch

+ mmap-fix-remap_file_pages-regression.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: mmap: fix remap_file_pages() regression
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     mmap-fix-remap_file_pages-regression.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mmap-fix-remap_file_pages-regression.patch

This patch will later appear in the mm-hotfixes-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Liam Howlett <liam.howlett@oracle.com>
Subject: mmap: fix remap_file_pages() regression
Date: Tue, 25 Oct 2022 16:12:49 +0000

When using the VMA iterator, the final execution will set the variable
'next' to NULL which causes the function to fail out.  Restore the break
in the loop to exit the VMA iterator early without clearing NULL fixes the
issue.

Link: https://lore.kernel.org/lkml/29344.1666681759@jrobl/
Link: https://lkml.kernel.org/r/20221025161222.2634030-1-Liam.Howlett@oracle.com
Fixes: 763ecb035029 (mm: remove the vma linked list)
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reported-by: "J. R. Okajima" <hooanon05g@gmail.com>
Tested-by: "J. R. Okajima" <hooanon05g@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---


--- a/mm/mmap.c~mmap-fix-remap_file_pages-regression
+++ a/mm/mmap.c
@@ -2852,6 +2852,9 @@ SYSCALL_DEFINE5(remap_file_pages, unsign
 			if (next->vm_flags != vma->vm_flags)
 				goto out;
 
+			if (start + size <= next->vm_end)
+				break;
+
 			prev = next;
 		}
 
_

Patches currently in -mm which might be from liam.howlett@oracle.com are

mmap-fix-remap_file_pages-regression.patch
maple_tree-fix-mas_find_rev-comment.patch
maple_tree-update-copyright-dates-for-test-code.patch