[PATCH 4.19 18/86] IB/umem: fix reference count leak in ib_umem_odp_get()

Greg Kroah-Hartman
2020-07-27T14:39:51Z

From: Yang Yingliang <yangyingliang@huawei.com>

Add missing mmput() on error path to avoid ref-count leak.

This problem is introduced by 79bb5b7ee177 ("RDMA/umem: Fix missing mmap_sem in get umem ODP call")
and resolved by f27a0d50a4bc ("RDMA/umem: Use umem->owning_mm inside ODP").
So, it's only needed in stable-4.14 and stable-4.19.

Fixes: 79bb5b7ee177 ("RDMA/umem: Fix missing mmap_sem in get umem ODP call")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/infiniband/core/umem_odp.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/infiniband/core/umem_odp.c
+++ b/drivers/infiniband/core/umem_odp.c
@@ -356,7 +356,8 @@ int ib_umem_odp_get(struct ib_ucontext *
vma = find_vma(mm, ib_umem_start(umem));
if (!vma || !is_vm_hugetlb_page(vma)) {
up_read(&mm->mmap_sem);
- return -EINVAL;
+ ret_val = -EINVAL;
+ goto out_mm;
}
h = hstate_vma(vma);
umem->page_shift = huge_page_shift(h);