Patch "wifi: iwl4965: Add missing check for create_singlethread_workqueue()" has been added to the 5.4-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    wifi: iwl4965: Add missing check for create_singlethread_workqueue()

to the 5.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     wifi-iwl4965-add-missing-check-for-create_singlethre.patch
and it can be found in the queue-5.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 9654d67377394909178c1d37b15f08004d3a601a
Author: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>
Date:   Thu Feb 9 09:07:48 2023 +0800

    wifi: iwl4965: Add missing check for create_singlethread_workqueue()
    
    [ Upstream commit 26e6775f75517ad6844fe5b79bc5f3fa8c22ee61 ]
    
    Add the check for the return value of the create_singlethread_workqueue()
    in order to avoid NULL pointer dereference.
    
    Fixes: b481de9ca074 ("[IWLWIFI]: add iwlwifi wireless drivers")
    Signed-off-by: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>
    Acked-by: Stanislaw Gruszka <stf_xl@xxxxx>
    Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxx>
    Link: https://lore.kernel.org/r/20230209010748.45454-1-jiasheng@xxxxxxxxxxx
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/net/wireless/intel/iwlegacy/4965-mac.c b/drivers/net/wireless/intel/iwlegacy/4965-mac.c
index 5fe17039a3375..feeb57cadc1ca 100644
--- a/drivers/net/wireless/intel/iwlegacy/4965-mac.c
+++ b/drivers/net/wireless/intel/iwlegacy/4965-mac.c
@@ -6217,10 +6217,12 @@ il4965_bg_txpower_work(struct work_struct *work)
 	mutex_unlock(&il->mutex);
 }
 
-static void
+static int
 il4965_setup_deferred_work(struct il_priv *il)
 {
 	il->workqueue = create_singlethread_workqueue(DRV_NAME);
+	if (!il->workqueue)
+		return -ENOMEM;
 
 	init_waitqueue_head(&il->wait_command_queue);
 
@@ -6241,6 +6243,8 @@ il4965_setup_deferred_work(struct il_priv *il)
 	tasklet_init(&il->irq_tasklet,
 		     il4965_irq_tasklet,
 		     (unsigned long)il);
+
+	return 0;
 }
 
 static void
@@ -6630,7 +6634,10 @@ il4965_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 		goto out_disable_msi;
 	}
 
-	il4965_setup_deferred_work(il);
+	err = il4965_setup_deferred_work(il);
+	if (err)
+		goto out_free_irq;
+
 	il4965_setup_handlers(il);
 
 	/*********************************************
@@ -6668,6 +6675,7 @@ il4965_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 out_destroy_workqueue:
 	destroy_workqueue(il->workqueue);
 	il->workqueue = NULL;
+out_free_irq:
 	free_irq(il->pci_dev->irq, il);
 out_disable_msi:
 	pci_disable_msi(il->pci_dev);