[PATCH 4.4 52/87] RDS: null pointer dereference in rds_atomic_free_op

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Mohamed Ghannam <simo.ghannam@xxxxxxxxx>


[ Upstream commit 7d11f77f84b27cef452cee332f4e469503084737 ]

set rm->atomic.op_active to 0 when rds_pin_pages() fails
or the user supplied address is invalid,
this prevents a NULL pointer usage in rds_atomic_free_op()

Signed-off-by: Mohamed Ghannam <simo.ghannam@xxxxxxxxx>
Acked-by: Santosh Shilimkar <santosh.shilimkar@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 net/rds/rdma.c |    1 +
 1 file changed, 1 insertion(+)

--- a/net/rds/rdma.c
+++ b/net/rds/rdma.c
@@ -869,6 +869,7 @@ int rds_cmsg_atomic(struct rds_sock *rs,
 err:
 	if (page)
 		put_page(page);
+	rm->atomic.op_active = 0;
 	kfree(rm->atomic.op_notifier);
 
 	return ret;