[PATCH 6.4 176/800] wifi: iwlwifi: pcie: fix NULL pointer dereference in iwl_pcie_irq_rx_msix_handler()

Greg Kroah-Hartman
2023-07-16T20:01:51Z

From: Anjaneyulu <pagadala.yesu.anjaneyulu@intel.com>

[ Upstream commit 1902f1953b8ba100ee8705cb8a6f1a9795550eca ]

rxq can be NULL only when trans_pcie->rxq is NULL and entry->entry
is zero. For the case when entry->entry is not equal to 0, rxq
won't be NULL even if trans_pcie->rxq is NULL. Modify checker to
check for trans_pcie->rxq.

Fixes: abc599efa67b ("iwlwifi: pcie: don't crash when rx queues aren't allocated in interrupt")
Signed-off-by: Anjaneyulu <pagadala.yesu.anjaneyulu@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230614123446.5a5eb3889a4a.I375a1d58f16b48cd2044e7b7caddae512d7c86fd@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/wireless/intel/iwlwifi/pcie/rx.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c
index 0d7890f99a5fb..90a46faaaffdf 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c
@@ -1636,14 +1636,14 @@ irqreturn_t iwl_pcie_irq_rx_msix_handler(int irq, void *dev_id)
struct msix_entry *entry = dev_id;
struct iwl_trans_pcie *trans_pcie = iwl_pcie_get_trans_pcie(entry);
struct iwl_trans *trans = trans_pcie->trans;
- struct iwl_rxq *rxq = &trans_pcie->rxq[entry->entry];
+ struct iwl_rxq *rxq;

trace_iwlwifi_dev_irq_msix(trans->dev, entry, false, 0, 0);

if (WARN_ON(entry->entry >= trans->num_rx_queues))
return IRQ_NONE;

- if (!rxq) {
+ if (!trans_pcie->rxq) {
if (net_ratelimit())
IWL_ERR(trans,
"[%d] Got MSI-X interrupt before we have Rx queues\n",
@@ -1651,6 +1651,7 @@ irqreturn_t iwl_pcie_irq_rx_msix_handler(int irq, void *dev_id)
return IRQ_NONE;
}

+ rxq = &trans_pcie->rxq[entry->entry];
lock_map_acquire(&trans->sync_cmd_lockdep_map);
IWL_DEBUG_ISR(trans, "[%d] Got interrupt\n", entry->entry);

--
2.39.2