From d64d6c5671db5e693a0caaee79f2571b098749c9 Mon Sep 17 00:00:00 2001 From: "himanshu.madhani@cavium.com" Date: Mon, 15 Jan 2018 20:46:46 -0800 Subject: [PATCH] scsi: qla2xxx: Fix NULL pointer crash due to probe failure 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: [] qla2x00_probe_one+0x18b6/0x2730 [qla2xxx] PGD 0 Oops: 0002 [#1] SMP Fixes: d74595278f4ab ("scsi: qla2xxx: Add multiple queue pair functionality."). Cc: # 4.10 Signed-off-by: Himanshu Madhani Signed-off-by: Martin K. Petersen --- drivers/scsi/qla2xxx/qla_os.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c index b21878a70f6e..12ee6e02d146 100644 --- a/drivers/scsi/qla2xxx/qla_os.c +++ b/drivers/scsi/qla2xxx/qla_os.c @@ -3035,9 +3035,6 @@ qla2x00_probe_one(struct pci_dev *pdev, const struct pci_device_id *id) 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; } @@ -3098,7 +3095,7 @@ qla2x00_probe_one(struct pci_dev *pdev, const struct pci_device_id *id) /* 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)) { @@ -3415,6 +3412,9 @@ 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: -- 2.39.5