Patch "wifi: iwl3945: 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: iwl3945: 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-iwl3945-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 6c6da5b1e82dd4eb84f22f5d2a9ca816aaf9e282
Author: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>
Date:   Wed Feb 8 14:30:32 2023 +0800

    wifi: iwl3945: Add missing check for create_singlethread_workqueue
    
    [ Upstream commit 1fdeb8b9f29dfd64805bb49475ac7566a3cb06cb ]
    
    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/20230208063032.42763-2-jiasheng@xxxxxxxxxxx
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/net/wireless/intel/iwlegacy/3945-mac.c b/drivers/net/wireless/intel/iwlegacy/3945-mac.c
index 206b43b9dff86..a1bd61d5e024d 100644
--- a/drivers/net/wireless/intel/iwlegacy/3945-mac.c
+++ b/drivers/net/wireless/intel/iwlegacy/3945-mac.c
@@ -3382,10 +3382,12 @@ static DEVICE_ATTR(dump_errors, 0200, NULL, il3945_dump_error_log);
  *
  *****************************************************************************/
 
-static void
+static int
 il3945_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);
 
@@ -3404,6 +3406,8 @@ il3945_setup_deferred_work(struct il_priv *il)
 	tasklet_init(&il->irq_tasklet,
 		     il3945_irq_tasklet,
 		     (unsigned long)il);
+
+	return 0;
 }
 
 static void
@@ -3725,7 +3729,10 @@ il3945_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	}
 
 	il_set_rxon_channel(il, &il->bands[NL80211_BAND_2GHZ].channels[5]);
-	il3945_setup_deferred_work(il);
+	err = il3945_setup_deferred_work(il);
+	if (err)
+		goto out_remove_sysfs;
+
 	il3945_setup_handlers(il);
 	il_power_initialize(il);
 
@@ -3737,7 +3744,7 @@ il3945_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	err = il3945_setup_mac(il);
 	if (err)
-		goto out_remove_sysfs;
+		goto out_destroy_workqueue;
 
 	il_dbgfs_register(il, DRV_NAME);
 
@@ -3746,9 +3753,10 @@ il3945_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	return 0;
 
-out_remove_sysfs:
+out_destroy_workqueue:
 	destroy_workqueue(il->workqueue);
 	il->workqueue = NULL;
+out_remove_sysfs:
 	sysfs_remove_group(&pdev->dev.kobj, &il3945_attribute_group);
 out_release_irq:
 	free_irq(il->pci_dev->irq, il);