+ mm-mremap-fix-unaccount-of-memory-on-vma_merge-failure.patch added to mm-unstable branch

+ mm-mremap-fix-unaccount-of-memory-on-vma_merge-failure.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/mremap: fix unaccount of memory on vma_merge() failure
has been added to the -mm mm-unstable branch.  Its filename is
     mm-mremap-fix-unaccount-of-memory-on-vma_merge-failure.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-mremap-fix-unaccount-of-memory-on-vma_merge-failure.patch

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

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------------------------------------------------------
From: Anthony Yznaga <anthony.yznaga@oracle.com>
Subject: mm/mremap: fix unaccount of memory on vma_merge() failure
Date: Tue, 29 Aug 2023 17:45:49 -0700

Fix mremap so that only accounted memory is unaccounted if the mapping is
expandable but vma_merge() fails.

Link: https://lkml.kernel.org/r/20230830004549.16131-1-anthony.yznaga@oracle.com
Fixes: fdbef6149135 ("mm/mremap: don't account pages in vma_to_resize()")
Signed-off-by: Anthony Yznaga <anthony.yznaga@oracle.com>
Acked-by: Brian Geffon <bgeffon@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/mremap.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/mm/mremap.c~mm-mremap-fix-unaccount-of-memory-on-vma_merge-failure
+++ a/mm/mremap.c
@@ -1037,12 +1037,14 @@ SYSCALL_DEFINE5(mremap, unsigned long, a
 			pgoff_t extension_pgoff = vma->vm_pgoff +
 				((extension_start - vma->vm_start) >> PAGE_SHIFT);
 			VMA_ITERATOR(vmi, mm, extension_start);
+			long charged = 0;
 
 			if (vma->vm_flags & VM_ACCOUNT) {
 				if (security_vm_enough_memory_mm(mm, pages)) {
 					ret = -ENOMEM;
 					goto out;
 				}
+				charged = pages;
 			}
 
 			/*
@@ -1058,7 +1060,7 @@ SYSCALL_DEFINE5(mremap, unsigned long, a
 				vma->vm_file, extension_pgoff, vma_policy(vma),
 				vma->vm_userfaultfd_ctx, anon_vma_name(vma));
 			if (!vma) {
-				vm_unacct_memory(pages);
+				vm_unacct_memory(charged);
 				ret = -ENOMEM;
 				goto out;
 			}
_

Patches currently in -mm which might be from anthony.yznaga@oracle.com are

mm-mremap-fix-unaccount-of-memory-on-vma_merge-failure.patch