[PATCH] mm/vmalloc.c: Fix potential memory leak

From: Miaohe Lin
Date: Thu Jan 07 2021 - 07:37:12 EST


In VM_MAP_PUT_PAGES case, we should put pages and free array in vfree. But
we missed to set area->nr_pages in vmap(). So we would failed to put pages
in __vunmap() because area->nr_pages = 0.

Fixes: b944afc9d64d ("mm: add a VM_MAP_PUT_PAGES flag for vmap")
Signed-off-by: Shijie Luo <luoshijie1@xxxxxxxxxx>
Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
---
mm/vmalloc.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 6507a579ff88..8ab83fbecadd 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2421,8 +2421,10 @@ void *vmap(struct page **pages, unsigned int count,
return NULL;
}

- if (flags & VM_MAP_PUT_PAGES)
+ if (flags & VM_MAP_PUT_PAGES) {
area->pages = pages;
+ area->nr_pages = count;
+ }
return area->addr;
}
EXPORT_SYMBOL(vmap);
--
2.19.1