Patch "scsi: qla2xxx: Fix NULL pointer crash due to probe failure" has been added to the 4.14-stable tree

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

scsi: qla2xxx: Fix NULL pointer crash due to probe failure

to the 4.14-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:
scsi-qla2xxx-fix-null-pointer-crash-due-to-probe-failure.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: "[email protected]" <[email protected]>
Date: Mon, 15 Jan 2018 20:46:46 -0800
Subject: scsi: qla2xxx: Fix NULL pointer crash due to probe failure

From: [email protected] <[email protected]>

commit d64d6c5671db5e693a0caaee79f2571b098749c9 upstream.

This patch fixes regression added by commit d74595278f4ab ("scsi: qla2xxx: Add multiple queue pair functionality.").

When driver is not able to get reqeusted IRQs from the system, driver will attempt tp clean up memory before failing hardware probe. During this cleanup, driver assigns NULL value to the pointer which has not been allocated by driver yet. This results in a NULL pointer access.

Log file will show following message and stack trace

qla2xxx [0000:a3:00.1]-00c7:21: MSI-X: Failed to enable support, giving up -- 32/-1. qla2xxx [0000:a3:00.1]-0037:21: Falling back-to MSI mode --1.
qla2xxx [0000:a3:00.1]-003a:21: Failed to reserve interrupt 821 already in use.

BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [<ffffffffc010c4b6>] qla2x00_probe_one+0x18b6/0x2730 [qla2xxx]
PGD 0
Oops: 0002 [#1] SMP

---
 drivers/scsi/qla2xxx/qla_os.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

@@ -3003,9 +3003,6 @@ qla2x00_probe_one(struct pci_dev *pdev,
 	base_vha = qla2x00_create_host(sht, ha);
 	if (!base_vha) {
 		ret = -ENOMEM;
-		qla2x00_mem_free(ha);
-		qla2x00_free_req_que(ha, req);
-		qla2x00_free_rsp_que(ha, rsp);
 		goto probe_hw_failed;
 	}
 

@@ -3066,7 +3063,7 @@ qla2x00_probe_one(struct pci_dev *pdev,
 	/* Set up the irqs */
 	ret = qla2x00_request_irqs(ha, rsp);
 	if (ret)
-		goto probe_init_failed;
+		goto probe_hw_failed;
 
 	/* Alloc arrays of request and response ring ptrs */
 	if (!qla2x00_alloc_queues(ha, req, rsp)) {

@@ -3374,6 +3371,9 @@ probe_failed:
 	scsi_host_put(base_vha->host);
 
 probe_hw_failed:
+	qla2x00_mem_free(ha);
+	qla2x00_free_req_que(ha, req);
+	qla2x00_free_rsp_que(ha, rsp);
 	qla2x00_clear_drv_active(ha);
 
 iospace_config_failed:

Patches currently in stable-queue which might be from [email protected] are

queue-4.14/scsi-qla2xxx-fix-null-pointer-crash-due-to-active-timer-for-abts.patch queue-4.14/scsi-qla2xxx-fix-recursion-while-sending-terminate-exchange.patch queue-4.14/scsi-qla2xxx-fix-null-pointer-crash-due-to-probe-failure.patch