[PATCH 5.12 505/677] IB/hfi1: Use kzalloc() for mmu_rb_handler allocation

From: Greg Kroah-Hartman
Date: Wed May 12 2021 - 14:58:18 EST


From: Mike Marciniszyn <mike.marciniszyn@xxxxxxxxxxxxxxxxxxxx>

[ Upstream commit ca5f72568e034e1295a7ae350b1f786fcbfb2848 ]

The code currently assumes that the mmu_notifier struct
embedded in mmu_rb_handler only contains two fields.

There are now extra fields:

struct mmu_notifier {
struct hlist_node hlist;
const struct mmu_notifier_ops *ops;
struct mm_struct *mm;
struct rcu_head rcu;
unsigned int users;
};

Given that there in no init for the mmu_notifier, a kzalloc() should
be used to insure that any newly added fields are given a predictable
initial value of zero.

Fixes: 06e0ffa69312 ("IB/hfi1: Re-factor MMU notification code")
Link: https://lore.kernel.org/r/1617026056-50483-9-git-send-email-dennis.dalessandro@xxxxxxxxxxxxxxxxxxxx
Reviewed-by: Adam Goldman <adam.goldman@xxxxxxxxx>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/infiniband/hw/hfi1/mmu_rb.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/infiniband/hw/hfi1/mmu_rb.c b/drivers/infiniband/hw/hfi1/mmu_rb.c
index f3fb28e3d5d7..d213f65d4cdd 100644
--- a/drivers/infiniband/hw/hfi1/mmu_rb.c
+++ b/drivers/infiniband/hw/hfi1/mmu_rb.c
@@ -89,7 +89,7 @@ int hfi1_mmu_rb_register(void *ops_arg,
struct mmu_rb_handler *h;
int ret;

- h = kmalloc(sizeof(*h), GFP_KERNEL);
+ h = kzalloc(sizeof(*h), GFP_KERNEL);
if (!h)
return -ENOMEM;

--
2.30.2