[PATCH] mm/migrate_device: fix pgtable leak in migrate_vma_insert_huge_pmd_page

[Sunny Patel <nueralspacetech@gmail.com>]

When migrate_vma_insert_huge_pmd_page() jumps to unlock_abort due
to a PMD check failure, the pgtable allocated earlier via
pte_alloc_one() is never freed, causing a memory leak.

Add a pte_free() call in the unlock_abort error path to release
the pgtable before returning.

Signed-off-by: Sunny Patel <nueralspacetech@gmail.com>
---
 mm/migrate_device.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/mm/migrate_device.c b/mm/migrate_device.c
index fbfe5715f635..457bab5c7c31 100644
--- a/mm/migrate_device.c
+++ b/mm/migrate_device.c
@@ -893,6 +893,7 @@ static int migrate_vma_insert_huge_pmd_page(struct migrate_vma *migrate,
 
 unlock_abort:
 	spin_unlock(ptl);
+	pte_free(vma->vm_mm, pgtable);
 abort:
 	for (i = 0; i < HPAGE_PMD_NR; i++)
 		src[i] &= ~MIGRATE_PFN_MIGRATE;
-- 
2.43.0