6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Sean Nyekjaer <sean@xxxxxxxxxx>
[ Upstream commit 1499b89289bf272fd83cb296c82fb5519d0fe93f ]
Provide a list of valid protocols for which the driver will provide
it's deferred xmit handler.
When using DSA_TAG_PROTO_KSZ8795 protocol, it does not provide a
"connect" method, therefor ksz_connect() is not allocating ksz_tagger_data.
This avoids the following null pointer dereference:
ksz_connect_tag_protocol from dsa_register_switch+0x9ac/0xee0
dsa_register_switch from ksz_switch_register+0x65c/0x828
ksz_switch_register from ksz_spi_probe+0x11c/0x168
ksz_spi_probe from spi_probe+0x84/0xa8
spi_probe from really_probe+0xc8/0x2d8
Fixes: ab32f56a4100 ("net: dsa: microchip: ptp: add packet transmission timestamping")
Signed-off-by: Sean Nyekjaer <sean@xxxxxxxxxx>
Reviewed-by: Florian Fainelli <florian.fainelli@xxxxxxxxxxxx>
Reviewed-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
Link: https://lore.kernel.org/r/20231206071655.1626479-1-sean@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/dsa/microchip/ksz_common.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)
diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index 42db7679c3606..286e20f340e5c 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -2624,10 +2624,18 @@ static int ksz_connect_tag_protocol(struct dsa_switch *ds,
{
struct ksz_tagger_data *tagger_data;
- tagger_data = ksz_tagger_data(ds);
- tagger_data->xmit_work_fn = ksz_port_deferred_xmit;
-
- return 0;
+ switch (proto) {
+ case DSA_TAG_PROTO_KSZ8795:
+ return 0;
+ case DSA_TAG_PROTO_KSZ9893:
+ case DSA_TAG_PROTO_KSZ9477:
+ case DSA_TAG_PROTO_LAN937X:
+ tagger_data = ksz_tagger_data(ds);
+ tagger_data->xmit_work_fn = ksz_port_deferred_xmit;
+ return 0;
+ default:
+ return -EPROTONOSUPPORT;
+ }
}
static int ksz_port_vlan_filtering(struct dsa_switch *ds, int port,
--
2.42.0
