[PATCH 5.11 408/775] IB/cm: Avoid a loop when device has 255 ports

[Greg Kroah-Hartman]

From: Parav Pandit <parav@xxxxxxxxxx>

[ Upstream commit 131be26750379592f0dd6244b2a90bbb504a10bb ]

When RDMA device has 255 ports, loop iterator i overflows.  Due to which
cm_add_one() port iterator loops infinitely.  Use core provided port
iterator to avoid the infinite loop.

Fixes: a977049dacde ("[PATCH] IB: Add the kernel CM implementation")
Link: https://lore.kernel.org/r/20210127150010.1876121-9-leon@xxxxxxxxxx
Signed-off-by: Mark Bloch <mbloch@xxxxxxxxxx>
Signed-off-by: Parav Pandit <parav@xxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/infiniband/core/cm.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/infiniband/core/cm.c b/drivers/infiniband/core/cm.c
index 98165589c8ab6..be996dba040cc 100644
--- a/drivers/infiniband/core/cm.c
+++ b/drivers/infiniband/core/cm.c
@@ -4333,7 +4333,7 @@ static int cm_add_one(struct ib_device *ib_device)
 	unsigned long flags;
 	int ret;
 	int count = 0;
-	u8 i;
+	unsigned int i;
 
 	cm_dev = kzalloc(struct_size(cm_dev, port, ib_device->phys_port_cnt),
 			 GFP_KERNEL);
@@ -4345,7 +4345,7 @@ static int cm_add_one(struct ib_device *ib_device)
 	cm_dev->going_down = 0;
 
 	set_bit(IB_MGMT_METHOD_SEND, reg_req.method_mask);
-	for (i = 1; i <= ib_device->phys_port_cnt; i++) {
+	rdma_for_each_port (ib_device, i) {
 		if (!rdma_cap_ib_cm(ib_device, i))
 			continue;
 
@@ -4431,7 +4431,7 @@ static void cm_remove_one(struct ib_device *ib_device, void *client_data)
 		.clr_port_cap_mask = IB_PORT_CM_SUP
 	};
 	unsigned long flags;
-	int i;
+	unsigned int i;
 
 	write_lock_irqsave(&cm.device_lock, flags);
 	list_del(&cm_dev->list);
@@ -4441,7 +4441,7 @@ static void cm_remove_one(struct ib_device *ib_device, void *client_data)
 	cm_dev->going_down = 1;
 	spin_unlock_irq(&cm.lock);
 
-	for (i = 1; i <= ib_device->phys_port_cnt; i++) {
+	rdma_for_each_port (ib_device, i) {
 		if (!rdma_cap_ib_cm(ib_device, i))
 			continue;
 
-- 
2.27.0