[PATCH 4.9 46/66] vmxnet3: repair memory leak

From: Greg Kroah-Hartman
Date: Mon Jan 29 2018 - 12:08:09 EST


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

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

From: Neil Horman <nhorman@xxxxxxxxxxxxx>


[ Upstream commit 848b159835ddef99cc4193083f7e786c3992f580 ]

with the introduction of commit
b0eb57cb97e7837ebb746404c2c58c6f536f23fa, it appears that rq->buf_info
is improperly handled. While it is heap allocated when an rx queue is
setup, and freed when torn down, an old line of code in
vmxnet3_rq_destroy was not properly removed, leading to rq->buf_info[0]
being set to NULL prior to its being freed, causing a memory leak, which
eventually exhausts the system on repeated create/destroy operations
(for example, when the mtu of a vmxnet3 interface is changed
frequently.

Fix is pretty straight forward, just move the NULL set to after the
free.

Tested by myself with successful results

Applies to net, and should likely be queued for stable, please

Signed-off-by: Neil Horman <nhorman@xxxxxxxxxxxxx>
Reported-By: boyang@xxxxxxxxxx
CC: boyang@xxxxxxxxxx
CC: Shrikrishna Khare <skhare@xxxxxxxxxx>
CC: "VMware, Inc." <pv-drivers@xxxxxxxxxx>
CC: David S. Miller <davem@xxxxxxxxxxxxx>
Acked-by: Shrikrishna Khare <skhare@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/vmxnet3/vmxnet3_drv.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/vmxnet3/vmxnet3_drv.c
+++ b/drivers/net/vmxnet3/vmxnet3_drv.c
@@ -1616,7 +1616,6 @@ static void vmxnet3_rq_destroy(struct vm
rq->rx_ring[i].basePA);
rq->rx_ring[i].base = NULL;
}
- rq->buf_info[i] = NULL;
}

if (rq->data_ring.base) {
@@ -1638,6 +1637,7 @@ static void vmxnet3_rq_destroy(struct vm
(rq->rx_ring[0].size + rq->rx_ring[1].size);
dma_free_coherent(&adapter->pdev->dev, sz, rq->buf_info[0],
rq->buf_info_pa);
+ rq->buf_info[0] = rq->buf_info[1] = NULL;
}
}