Commit 7f31cced authored by Liam Howlett's avatar Liam Howlett Committed by Andrew Morton
Browse files

nommu: fix memory leak in do_mmap() error path 

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: 8220543d ("nommu: remove uses of VMA linked list")
Signed-off-by: default avatarLiam 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: default avatarAndrew Morton <akpm@linux-foundation.org>
parent bf61acbe

mm/nommu.c

+1 −1
Original line number Diff line number Diff line
@@ -1240,6 +1240,7 @@ unsigned long do_mmap(struct file *file, 
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 @@ unsigned long do_mmap(struct file *file, 


sharing_violation:

	up_write(&nommu_region_sem);

	mas_destroy(&mas);

	pr_warn("Attempt to share mismatched mappings\n");

	ret = -EINVAL;

	goto error;