From a88d9db94c4c9fb2b6ce9f5748928bef46aa9885 Mon Sep 17 00:00:00 2001 From: Vikram Auradkar Date: Thu, 14 Nov 2019 15:39:04 +0530 Subject: scsi: pm80xx: Fix dereferencing dangling pointer sas_task structure should not be used after task_done is called. If the device is gone or not attached, we call task_done on t and continue to use in the sas_task in rest of the function. task_done is pointing to sas_ata_task_done, may free the memory associated with the task before returning. Link: https://lore.kernel.org/r/20191114100910.6153-8-deepak.ukey@microchip.com Acked-by: Jack Wang Signed-off-by: Vikram Auradkar Signed-off-by: Deepak Ukey Signed-off-by: Viswas G Signed-off-by: Martin K. Petersen --- drivers/scsi/pm8001/pm8001_sas.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'drivers/scsi/pm8001') diff --git a/drivers/scsi/pm8001/pm8001_sas.c b/drivers/scsi/pm8001/pm8001_sas.c index 447a66d60275..4491de8d40fc 100644 --- a/drivers/scsi/pm8001/pm8001_sas.c +++ b/drivers/scsi/pm8001/pm8001_sas.c @@ -388,6 +388,7 @@ static int pm8001_task_exec(struct sas_task *task, struct pm8001_ccb_info *ccb; u32 tag = 0xdeadbeef, rc = 0, n_elem = 0; unsigned long flags = 0; + enum sas_protocol task_proto = t->task_proto; if (!dev->port) { struct task_status_struct *tsm = &t->task_status; @@ -412,7 +413,7 @@ static int pm8001_task_exec(struct sas_task *task, pm8001_dev = dev->lldd_dev; port = &pm8001_ha->port[sas_find_local_port_id(dev)]; if (DEV_IS_GONE(pm8001_dev) || !port->port_attached) { - if (sas_protocol_ata(t->task_proto)) { + if (sas_protocol_ata(task_proto)) { struct task_status_struct *ts = &t->task_status; ts->resp = SAS_TASK_UNDELIVERED; ts->stat = SAS_PHY_DOWN; @@ -434,7 +435,7 @@ static int pm8001_task_exec(struct sas_task *task, goto err_out; ccb = &pm8001_ha->ccb_info[tag]; - if (!sas_protocol_ata(t->task_proto)) { + if (!sas_protocol_ata(task_proto)) { if (t->num_scatter) { n_elem = dma_map_sg(pm8001_ha->dev, t->scatter, @@ -454,7 +455,7 @@ static int pm8001_task_exec(struct sas_task *task, ccb->ccb_tag = tag; ccb->task = t; ccb->device = pm8001_dev; - switch (t->task_proto) { + switch (task_proto) { case SAS_PROTOCOL_SMP: rc = pm8001_task_prep_smp(pm8001_ha, ccb); break; @@ -471,8 +472,7 @@ static int pm8001_task_exec(struct sas_task *task, break; default: dev_printk(KERN_ERR, pm8001_ha->dev, - "unknown sas_task proto: 0x%x\n", - t->task_proto); + "unknown sas_task proto: 0x%x\n", task_proto); rc = -EINVAL; break; } @@ -495,7 +495,7 @@ err_out_tag: pm8001_tag_free(pm8001_ha, tag); err_out: dev_printk(KERN_ERR, pm8001_ha->dev, "pm8001 exec failed[%d]!\n", rc); - if (!sas_protocol_ata(t->task_proto)) + if (!sas_protocol_ata(task_proto)) if (n_elem) dma_unmap_sg(pm8001_ha->dev, t->scatter, t->num_scatter, t->data_dir); -- cgit v1.2.3