From ab1068d6866e28bf6427ceaea681a381e5870a4a Mon Sep 17 00:00:00 2001 From: Hao Wei Tee Date: Tue, 29 May 2018 10:25:17 +0300 Subject: [PATCH] iwlwifi: pcie: compare with number of IRQs requested for, not number of CPUs When there are 16 or more logical CPUs, we request for `IWL_MAX_RX_HW_QUEUES` (16) IRQs only as we limit to that number of IRQs, but later on we compare the number of IRQs returned to nr_online_cpus+2 instead of max_irqs, the latter being what we actually asked for. This ends up setting num_rx_queues to 17 which causes lots of out-of-bounds array accesses later on. Compare to max_irqs instead, and also add an assertion in case num_rx_queues > IWM_MAX_RX_HW_QUEUES. This fixes https://bugzilla.kernel.org/show_bug.cgi?id=199551 Fixes: 2e5d4a8f61dc ("iwlwifi: pcie: Add new configuration to enable MSIX") Signed-off-by: Hao Wei Tee Tested-by: Sara Sharon Signed-off-by: Luca Coelho Signed-off-by: Kalle Valo --- drivers/net/wireless/intel/iwlwifi/pcie/trans.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c index f8a0234d332c2a..5517ea4c2aa0b7 100644 --- a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c +++ b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c @@ -1590,14 +1590,13 @@ static void iwl_pcie_set_interrupt_capa(struct pci_dev *pdev, struct iwl_trans *trans) { struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans); - int max_irqs, num_irqs, i, ret, nr_online_cpus; + int max_irqs, num_irqs, i, ret; u16 pci_cmd; if (!trans->cfg->mq_rx_supported) goto enable_msi; - nr_online_cpus = num_online_cpus(); - max_irqs = min_t(u32, nr_online_cpus + 2, IWL_MAX_RX_HW_QUEUES); + max_irqs = min_t(u32, num_online_cpus() + 2, IWL_MAX_RX_HW_QUEUES); for (i = 0; i < max_irqs; i++) trans_pcie->msix_entries[i].entry = i; @@ -1623,16 +1622,17 @@ static void iwl_pcie_set_interrupt_capa(struct pci_dev *pdev, * Two interrupts less: non rx causes shared with FBQ and RSS. * More than two interrupts: we will use fewer RSS queues. */ - if (num_irqs <= nr_online_cpus) { + if (num_irqs <= max_irqs - 2) { trans_pcie->trans->num_rx_queues = num_irqs + 1; trans_pcie->shared_vec_mask = IWL_SHARED_IRQ_NON_RX | IWL_SHARED_IRQ_FIRST_RSS; - } else if (num_irqs == nr_online_cpus + 1) { + } else if (num_irqs == max_irqs - 1) { trans_pcie->trans->num_rx_queues = num_irqs; trans_pcie->shared_vec_mask = IWL_SHARED_IRQ_NON_RX; } else { trans_pcie->trans->num_rx_queues = num_irqs - 1; } + WARN_ON(trans_pcie->trans->num_rx_queues > IWL_MAX_RX_HW_QUEUES); trans_pcie->alloc_vecs = num_irqs; trans_pcie->msix_enabled = true;