+ nommu-fix-memory-leak-in-do_mmap-error-path.patch added to mm-hotfixes-unstable branch

+ nommu-fix-memory-leak-in-do_mmap-error-path.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: nommu: fix memory leak in do_mmap() error path
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     nommu-fix-memory-leak-in-do_mmap-error-path.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/nommu-fix-memory-leak-in-do_mmap-error-path.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: nommu: fix memory leak in do_mmap() error path
Date: Mon, 9 Jan 2023 20:55:21 +0000

The preallocation of the maple tree nodes may leak if the error path to
"error_just_free" is taken.  Fix this by moving the freeing of the maple
tree nodes to a shared location for all error paths.

Link: https://lkml.kernel.org/r/20230109205507.955577-1-Liam.Howlett@oracle.com
Fixes: 8220543df148 ("nommu: remove uses of VMA linked list")
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yu Zhao <yuzhao@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/nommu.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/nommu.c~nommu-fix-memory-leak-in-do_mmap-error-path
+++ a/mm/nommu.c
@@ -1240,6 +1240,7 @@ share:
 error_just_free:
 	up_write(&nommu_region_sem);
 error:
+	mas_destroy(&mas);
 	if (region->vm_file)
 		fput(region->vm_file);
 	kmem_cache_free(vm_region_jar, region);
@@ -1250,7 +1251,6 @@ error:
 
 sharing_violation:
 	up_write(&nommu_region_sem);
-	mas_destroy(&mas);
 	pr_warn("Attempt to share mismatched mappings\n");
 	ret = -EINVAL;
 	goto error;
_

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

nommu-fix-memory-leak-in-do_mmap-error-path.patch
nommu-fix-do_munmap-error-path.patch
nommu-fix-split_vma-map_count-error.patch
maple_tree-remove-gfp_zero-from-kmem_cache_alloc-and-kmem_cache_alloc_bulk.patch