2019-02-25 07:22:59

by Wen Yang

Subject: [PATCH v2] net: dsa: fix a leaked reference by adding missing of_node_put

The call to of_parse_phandle returns a node pointer with refcount
incremented thus it must be explicitly decremented after the last
usage.

Detected by coccinelle with the following warnings:
./net/dsa/port.c:294:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 284, but without a corresponding object release within this function.
./net/dsa/dsa2.c:627:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 618, but without a corresponding object release within this function.
./net/dsa/dsa2.c:630:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 618, but without a corresponding object release within this function.
./net/dsa/dsa2.c:636:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 618, but without a corresponding object release within this function.
./net/dsa/dsa2.c:639:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 618, but without a corresponding object release within this function.

Signed-off-by: Wen Yang <[email protected]>
Reviewed-by: Vivien Didelot <[email protected]>
Reviewed-by: "David S. Miller" <[email protected]>
Cc: Andrew Lunn <[email protected]>
Cc: Vivien Didelot <[email protected]>
Cc: Florian Fainelli <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Vivien Didelot <[email protected]>
Cc: [email protected]
Cc: [email protected]
---
v2->v1: preserve the reverse christmas tree ordering of variables.

net/dsa/dsa2.c | 16 ++++++++++------
net/dsa/port.c | 1 +
2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/net/dsa/dsa2.c b/net/dsa/dsa2.c
index 8c431e0..c00ee464 100644
--- a/net/dsa/dsa2.c
+++ b/net/dsa/dsa2.c
@@ -612,8 +612,8 @@ static int dsa_switch_parse_ports_of(struct dsa_switch *ds,
{
struct device_node *ports, *port;
struct dsa_port *dp;
+ int err = 0;
u32 reg;
- int err;

ports = of_get_child_by_name(dn, "ports");
if (!ports) {
@@ -624,19 +624,23 @@ static int dsa_switch_parse_ports_of(struct dsa_switch *ds,
for_each_available_child_of_node(ports, port) {
err = of_property_read_u32(port, "reg", &reg);
if (err)
- return err;
+ goto out_put_node;

- if (reg >= ds->num_ports)
- return -EINVAL;
+ if (reg >= ds->num_ports) {
+ err = -EINVAL;
+ goto out_put_node;
+ }

dp = &ds->ports[reg];

err = dsa_port_parse_of(dp, port);
if (err)
- return err;
+ goto out_put_node;
}

- return 0;
+out_put_node:
+ of_node_put(ports);
+ return err;
}

static int dsa_switch_parse_member_of(struct dsa_switch *ds,
diff --git a/net/dsa/port.c b/net/dsa/port.c
index 2d7e01b..a6d9a04 100644
--- a/net/dsa/port.c
+++ b/net/dsa/port.c
@@ -291,6 +291,7 @@ static struct phy_device *dsa_port_get_phy_device(struct dsa_port *dp)
return ERR_PTR(-EPROBE_DEFER);
}

+ of_node_put(phy_dn);
return phydev;
}

--
2.9.5

2019-02-25 17:37:43

by David Miller

Subject: Re: [PATCH v2] net: dsa: fix a leaked reference by adding missing of_node_put

From: Wen Yang <[email protected]>
Date: Mon, 25 Feb 2019 15:22:19 +0800

> The call to of_parse_phandle returns a node pointer with refcount
> incremented thus it must be explicitly decremented after the last
> usage.
>
> Detected by coccinelle with the following warnings:
> ./net/dsa/port.c:294:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 284, but without a corresponding object release within this function.
> ./net/dsa/dsa2.c:627:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 618, but without a corresponding object release within this function.
> ./net/dsa/dsa2.c:630:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 618, but without a corresponding object release within this function.
> ./net/dsa/dsa2.c:636:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 618, but without a corresponding object release within this function.
> ./net/dsa/dsa2.c:639:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 618, but without a corresponding object release within this function.
>
> Signed-off-by: Wen Yang <[email protected]>
> Reviewed-by: Vivien Didelot <[email protected]>
> Reviewed-by: "David S. Miller" <[email protected]>

Applied.