From f4445bb93d82a984657b469e63118c2794a4c3d3 Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Thu, 18 Oct 2018 18:59:39 +0200 Subject: [PATCH] scsi: hisi_sas: Fix NULL pointer dereference There is a NULL pointer dereference in case *slot* happens to be NULL at lines 1053 and 1878: struct hisi_sas_cq *cq = &hisi_hba->cq[slot->dlvry_queue]; Notice that *slot* is being NULL checked at lines 1057 and 1881: if (slot), which implies it may be NULL. Fix this by placing the declaration and definition of variable cq, which contains the pointer dereference slot->dlvry_queue, after slot has been properly NULL checked. Addresses-Coverity-ID: 1474515 ("Dereference before null check") Addresses-Coverity-ID: 1474520 ("Dereference before null check") Fixes: 584f53fe5f52 ("scsi: hisi_sas: Fix the race between IO completion and timeout for SMP/internal IO") Signed-off-by: Gustavo A. R. Silva Reviewed-by: Xiang Chen Signed-off-by: Martin K. Petersen --- drivers/scsi/hisi_sas/hisi_sas_main.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c index 2e5eaf1..b3f01d5 100644 --- a/drivers/scsi/hisi_sas/hisi_sas_main.c +++ b/drivers/scsi/hisi_sas/hisi_sas_main.c @@ -1050,11 +1050,11 @@ static int hisi_sas_exec_internal_tmf_task(struct domain_device *device, if ((task->task_state_flags & SAS_TASK_STATE_ABORTED)) { if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) { struct hisi_sas_slot *slot = task->lldd_task; - struct hisi_sas_cq *cq = - &hisi_hba->cq[slot->dlvry_queue]; dev_err(dev, "abort tmf: TMF task timeout and not done\n"); if (slot) { + struct hisi_sas_cq *cq = + &hisi_hba->cq[slot->dlvry_queue]; /* * flush tasklet to avoid free'ing task * before using task in IO completion @@ -1875,10 +1875,10 @@ hisi_sas_internal_task_abort(struct hisi_hba *hisi_hba, if ((task->task_state_flags & SAS_TASK_STATE_ABORTED)) { if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) { struct hisi_sas_slot *slot = task->lldd_task; - struct hisi_sas_cq *cq = - &hisi_hba->cq[slot->dlvry_queue]; if (slot) { + struct hisi_sas_cq *cq = + &hisi_hba->cq[slot->dlvry_queue]; /* * flush tasklet to avoid free'ing task * before using task in IO completion -- 2.7.4