> From: netdev-ow...@vger.kernel.org [mailto:netdev-ow...@vger.kernel.org] > On Behalf Of Jonathan Toppins > Sent: Friday, April 10, 2015 4:04 PM > To: Kirsher, Jeffrey T > Cc: Brandeburg, Jesse; Nelson, Shannon; Wyborny, Carolyn; Skidmore, Donald > C; Vick, Matthew; Ronciak, John; Williams, Mitch A; intel-wired- > l...@lists.osuosl.org; netdev@vger.kernel.org; go...@cumulusnetworks.com; > s...@cumulusnetworks.com > Subject: [PATCH v1 net-next 2/3] igb: move initialization of link > properties before igb_sw_init > > This is required otherwise the driver may experience a NULL ptr > dereference if CONFIG_PCI_IOV is set to yes. > > Since the code can follow the flow on init (driver insmod): > hw->mac.autoneg = false; (this is not set it is its default) > igb_probe() > +- igb_sw_init() > +- igb_probe_vfs() > +- igb_pci_enable_sriov() > +- igb_sriov_reinit() > +- igb_reset() > trimmed path is the same see call path for > igb_reset below > +- hw->mac.autoneg = true; > +- igb_reset() > > /* igb_reset() call chain */ > igb_reset() > +- hw->mac.ops.init_hw() == igb_init_hw_82575 > +- igb_setup_link() > +- hw->mac.ops.setup_physical_interface() == > igb_setup_copper_link_82575() > +- igb_setup_copper_link() > +- possible NULL dereference > > Pseudo code from igb_setup_copper_link(): > if (hw->mac.autoneg) { > /* setup link */ > } else { > hw->phy.ops.force_speed_duplex(hw); // <-- NULL deref here > } > > Since the way the current code is designed the driver will call > igb_setup_copper_link twice if SRIOV is configured to be enabled. The > call will occur once with autoneg == false and the second > time autoneg == true. Since the decision to call the function pointer > (hw->phy.ops.force_speed_duplex) is predicated on autoneg being set > correctly move the setting of these parameters to as early as possible > in the probe function. > > Signed-off-by: Jonathan Toppins <jtopp...@cumulusnetworks.com> > --- > drivers/net/ethernet/intel/igb/igb_main.c | 16 ++++++++-------- > 1 file changed, 8 insertions(+), 8 deletions(-)
Tested-by: Aaron Brown <aaron.f.br...@intel.com> -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
