[PATCH net] net: dsa: microchip: Don't try to read stats for unused ports

[PATCH net] net: dsa: microchip: Don't try to read stats for unused ports

[Robert Hancock]

If some of the switch ports were not listed in the device tree, due to
being unused, the ksz_mib_read_work function ended up accessing a NULL
dp->slave pointer and causing an oops. Skip checking statistics for any
unused ports.

Fixes: 7c6ff470aa867f53 ("net: dsa: microchip: add MIB counter reading
support")
Signed-off-by: Robert Hancock <hancock@sedsystems.ca>
---
 drivers/net/dsa/microchip/ksz_common.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index 39dace8..f46086f 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -83,6 +83,9 @@ static void ksz_mib_read_work(struct work_struct *work)
 	int i;
 
 	for (i = 0; i < dev->mib_port_cnt; i++) {
+		if (dsa_is_unused_port(dev->ds, i))
+			continue;
+
 		p = &dev->ports[i];
 		mib = &p->mib;
 		mutex_lock(&mib->cnt_mutex);
-- 
1.8.3.1

Re: [PATCH net] net: dsa: microchip: Don't try to read stats for unused ports

[Vivien Didelot]

On Wed, 12 Jun 2019 14:33:32 -0600, Robert Hancock <hancock@sedsystems.ca> wrote:
> If some of the switch ports were not listed in the device tree, due to
> being unused, the ksz_mib_read_work function ended up accessing a NULL
> dp->slave pointer and causing an oops. Skip checking statistics for any
> unused ports.
> 
> Fixes: 7c6ff470aa867f53 ("net: dsa: microchip: add MIB counter reading
> support")
> Signed-off-by: Robert Hancock <hancock@sedsystems.ca>

Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>

Re: [PATCH net] net: dsa: microchip: Don't try to read stats for unused ports

[Andrew Lunn]

On Wed, Jun 12, 2019 at 02:33:32PM -0600, Robert Hancock wrote:
> If some of the switch ports were not listed in the device tree, due to
> being unused, the ksz_mib_read_work function ended up accessing a NULL
> dp->slave pointer and causing an oops. Skip checking statistics for any
> unused ports.
> 
> Fixes: 7c6ff470aa867f53 ("net: dsa: microchip: add MIB counter reading
> support")
> Signed-off-by: Robert Hancock <hancock@sedsystems.ca>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew

Re: [PATCH net] net: dsa: microchip: Don't try to read stats for unused ports

[Florian Fainelli]

On 6/12/19 1:33 PM, Robert Hancock wrote:
> If some of the switch ports were not listed in the device tree, due to
> being unused, the ksz_mib_read_work function ended up accessing a NULL
> dp->slave pointer and causing an oops. Skip checking statistics for any
> unused ports.
> 
> Fixes: 7c6ff470aa867f53 ("net: dsa: microchip: add MIB counter reading
> support")
> Signed-off-by: Robert Hancock <hancock@sedsystems.ca>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

Re: [PATCH net] net: dsa: microchip: Don't try to read stats for unused ports

[David Miller]

From: Robert Hancock <hancock@sedsystems.ca>
Date: Wed, 12 Jun 2019 14:33:32 -0600

> If some of the switch ports were not listed in the device tree, due to
> being unused, the ksz_mib_read_work function ended up accessing a NULL
> dp->slave pointer and causing an oops. Skip checking statistics for any
> unused ports.
> 
> Fixes: 7c6ff470aa867f53 ("net: dsa: microchip: add MIB counter reading
> support")
> Signed-off-by: Robert Hancock <hancock@sedsystems.ca>

Applied and queued up for -stable.