Commit cb06d102 authored Mar 21, 2014 by Christoph Paasch Committed by Jeff Kirsher Mar 21, 2014

igb: Fix Null-pointer dereference in igb_reset_q_vector



When igb_set_interrupt_capability() calls
igb_reset_interrupt_capability() (e.g., because CONFIG_PCI_MSI is unset),
num_q_vectors has been set but no vector has yet been allocated.

igb_reset_interrupt_capability() will then call igb_reset_q_vector,
which assumes that the vector is allocated. As this is not the case, we
are accessing a NULL-pointer.

This patch fixes it by checking that q_vector is indeed different from
NULL.

Fixes: 02ef6e1d (igb: Fix queue allocation method to accommodate changing during runtime)
Cc: Carolyn Wyborny <carolyn.wyborny@intel.com>
Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Tested-by: Jeff Pieper <jeffrey.e.pieper@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

parent 0f49da0e

drivers/net/ethernet/intel/igb/igb_main.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -1035,6 +1035,12 @@ static void igb_reset_q_vector(struct igb_adapter *adapter, int v_idx)
		{
		struct igb_q_vector *q_vector = adapter->q_vector[v_idx];

		/* Coming from igb_set_interrupt_capability, the vectors are not yet
		* allocated. So, q_vector is NULL so we should stop here.
		*/
		if (!q_vector)
		return;

		if (q_vector->tx.ring)
		adapter->tx_ring[q_vector->tx.ring->queue_index] = NULL;