[merged mm-hotfixes-stable] mm-vma-correctly-unaccount-on-mmap_prepare-failure.patch removed from -mm tree

[merged mm-hotfixes-stable] mm-vma-correctly-unaccount-on-mmap_prepare-failure.patch removed from -mm tree

[Andrew Morton]

The quilt patch titled
     Subject: mm/vma: correctly unaccount on mmap_prepare() failure
has been removed from the -mm tree.  Its filename was
     mm-vma-correctly-unaccount-on-mmap_prepare-failure.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: "Lorenzo Stoakes (ARM)" <ljs@kernel.org>
Subject: mm/vma: correctly unaccount on mmap_prepare() failure
Date: Wed, 02 Sep 2026 19:08:08 +0100

__mmap_setup() accounts memory for relevant mappings via:

security_vm_enough_memory_mm()
  -> __vm_enough_memory()
    -> vm_acct_memory()

If __mmap_setup() fails, this indicates that this accounting did not take
place, and thus it's appropriate for __mmap_region() to jump to
abort_munmap.

However if call_mmap_prepare() fails, it also jumps there and any accounted
memory is not correctly unaccounted.

Fix this by handling each error separately.

Link: https://lore.kernel.org/20260902-fix-unaccount-mmap_prepare-v1-1-ea070189fdfb@kernel.org
Fixes: c84bf6dd2b83 ("mm: introduce new .mmap_prepare() file callback")
Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Pedro Falcato <pfalcato@suse.de>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/vma.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/mm/vma.c~mm-vma-correctly-unaccount-on-mmap_prepare-failure
+++ a/mm/vma.c
@@ -2859,10 +2859,12 @@ static unsigned long __mmap_region(struc
 	map.check_ksm_early = can_set_ksm_flags_early(&map);
 
 	error = __mmap_setup(&map, &desc, uf);
-	if (!error && have_mmap_prepare)
-		error = call_mmap_prepare(&map, &desc);
 	if (error)
 		goto abort_munmap;
+	if (have_mmap_prepare)
+		error = call_mmap_prepare(&map, &desc);
+	if (error)
+		goto unacct_error;
 
 	if (map.check_ksm_early)
 		update_ksm_flags(&map);
_

Patches currently in -mm which might be from ljs@kernel.org are

mm-vmpressure-remove-window-size-todo.patch
tools-testing-selftests-mm-add-missing-gitignore-entries.patch
mm-move-drivers-char-memc-to-mm-char-memc.patch
mm-implement-file_is_dev_zero-to-uniquely-identify-dev-zero.patch
mm-vma-only-permit-map_private-dev-zero-to-be-mapped-anonymous.patch
mm-vma-make-map_private-mapped-dev-zero-mappings-truly-anonymous.patch
tools-testing-vma-add-test-to-assert-map_private-dev-zero-is-anon.patch
tools-testing-selftests-mm-add-map_private-dev-zero-merge-tests.patch
mm-madvise-swap-in-cowd-map_private-file-mappings-on-madv_willneed.patch
mm-huge_memory-zap-deposited-page-tables-after-an-rcu-grace-period.patch
mm-enable-mmu_gather_rcu_table_free-for-most-2-level-architectures.patch
mm-enable-mmu_gather_rcu_table_free-for-mmu-riscv.patch
mm-enable-mmu_gather_rcu_table_free-for-mmu-arm.patch
mm-enable-mmu_gather_rcu_table_free-for-arc-microblaze-xtensa.patch
mm-enable-mmu_gather_rcu_table_free-for-sparc64.patch
mm-enable-mmu_gather_rcu_table_free-for-m68k-coldfire.patch
mm-enable-mmu_gather_rcu_table_free-for-sh-x2.patch
mm-enable-mmu_gather_rcu_table_free-for-m68k-motorola.patch
mm-enable-mmu_gather_rcu_table_free-for-sparc32.patch
mm-make-userland-page-table-freeing-rcu-safe.patch
mm-change-the-contract-for-free_pgtables-update-docs.patch