From cb06d102327eadcd1bdc480bfd9f8876251d1007 Mon Sep 17 00:00:00 2001 From: Christoph Paasch Date: Fri, 21 Mar 2014 03:48:19 -0700 Subject: [PATCH] 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: 02ef6e1d0b0023 (igb: Fix queue allocation method to accommodate changing during runtime) Cc: Carolyn Wyborny Signed-off-by: Christoph Paasch Tested-by: Jeff Pieper Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/igb/igb_main.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -1034,6 +1034,12 @@ static void igb_reset_q_vector(struct ig if (!q_vector) return; + /* 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;