| Message ID | 20210528071056.35252-1-sriranjani.p@samsung.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | net: stmmac: fix kernel panic due to NULL pointer dereference of mdio_bus_data | expand |
On Fri, 28 May 2021 12:40:56 +0530 Sriranjani P wrote: > Fixed link does not need mdio bus and in that case mdio_bus_data will > not be allocated. Before using mdio_bus_data we should check for NULL. > > This patch fix the kernel panic due to NULL pointer dereference of > mdio_bus_data when it is not allocated. > > Without this patch we do see following kernel crash caused due to kernel > NULL pointer dereference. Applied, thanks.
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 5d956a553434..5d7688d02255 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -1240,8 +1240,10 @@ static int stmmac_phy_setup(struct stmmac_priv *priv) priv->phylink_config.dev = &priv->dev->dev; priv->phylink_config.type = PHYLINK_NETDEV; priv->phylink_config.pcs_poll = true; - priv->phylink_config.ovr_an_inband = - priv->plat->mdio_bus_data->xpcs_an_inband; + if (priv->plat->mdio_bus_data) { + priv->phylink_config.ovr_an_inband = + priv->plat->mdio_bus_data->xpcs_an_inband; + } if (!fwnode) fwnode = dev_fwnode(priv->device);
Fixed link does not need mdio bus and in that case mdio_bus_data will not be allocated. Before using mdio_bus_data we should check for NULL. This patch fix the kernel panic due to NULL pointer dereference of mdio_bus_data when it is not allocated. Without this patch we do see following kernel crash caused due to kernel NULL pointer dereference. Call trace: stmmac_dvr_probe+0x3c/0x10b0 dwc_eth_dwmac_probe+0x224/0x378 platform_probe+0x68/0xe0 really_probe+0x130/0x3d8 driver_probe_device+0x68/0xd0 device_driver_attach+0x74/0x80 __driver_attach+0x58/0xf8 bus_for_each_dev+0x7c/0xd8 driver_attach+0x24/0x30 bus_add_driver+0x148/0x1f0 driver_register+0x64/0x120 __platform_driver_register+0x28/0x38 dwc_eth_dwmac_driver_init+0x1c/0x28 do_one_initcall+0x78/0x158 kernel_init_freeable+0x1f0/0x244 kernel_init+0x14/0x118 ret_from_fork+0x10/0x30 Code: f9002bfb 9113e2d9 910e6273 aa0003f7 (f9405c78) ---[ end trace 32d9d41562ddc081 ]--- Fixes: e5e5b771f684 ("net: stmmac: make in-band AN mode parsing is supported for non-DT") Signed-off-by: Sriranjani P <sriranjani.p@samsung.com> Signed-off-by: Pankaj Dubey <pankaj.dubey@samsung.com> --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)