summaryrefslogtreecommitdiff
path: root/drivers/scsi/NCR5380.c
diff options
context:
space:
mode:
authorFinn Thain <fthain@telegraphics.com.au>2016-02-23 10:07:09 +1100
committerMartin K. Petersen <martin.petersen@oracle.com>2016-03-01 09:38:58 -0500
commit8d5dbec3bcb24a7d071962448e0fecaca8c75cc7 (patch)
treeccb8868cb74c02bb283bf69d84722dcfe83e1e8c /drivers/scsi/NCR5380.c
parentccf6efd78317ef6265829c81a3e1a19f628b1a2d (diff)
ncr5380: Call scsi_eh_prep_cmnd() and scsi_eh_restore_cmnd() as and when appropriate
This bug causes the wrong command to have its sense pointer overwritten, which sometimes leads to a NULL pointer deref. Fix this by checking which command is being requeued before restoring the scsi_eh_save data. It turns out that some targets will disconnect a REQUEST SENSE command. The autosense algorithm doesn't anticipate this. Hence multiple commands can end up undergoing autosense simultaneously, and they will all try to use the same scsi_eh_save struct, which won't work. Defer autosense when the scsi_eh_save storage is in use by another command. Fixes: f27db8eb98a1 ("ncr5380: Fix autosense bugs") Reported-and-tested-by: Michael Schmitz <schmitzmic@gmail.com> Cc: <stable@vger.kernel.org> # 4.5 Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/NCR5380.c')
-rw-r--r--drivers/scsi/NCR5380.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/scsi/NCR5380.c b/drivers/scsi/NCR5380.c
index e8e579ad3d54..3eff2a69fe08 100644
--- a/drivers/scsi/NCR5380.c
+++ b/drivers/scsi/NCR5380.c
@@ -760,7 +760,7 @@ static struct scsi_cmnd *dequeue_next_cmd(struct Scsi_Host *instance)
struct NCR5380_cmd *ncmd;
struct scsi_cmnd *cmd;
- if (list_empty(&hostdata->autosense)) {
+ if (hostdata->sensing || list_empty(&hostdata->autosense)) {
list_for_each_entry(ncmd, &hostdata->unissued, list) {
cmd = NCR5380_to_scmd(ncmd);
dsprintk(NDEBUG_QUEUES, instance, "dequeue: cmd=%p target=%d busy=0x%02x lun=%llu\n",
@@ -793,7 +793,7 @@ static void requeue_cmd(struct Scsi_Host *instance, struct scsi_cmnd *cmd)
struct NCR5380_hostdata *hostdata = shost_priv(instance);
struct NCR5380_cmd *ncmd = scsi_cmd_priv(cmd);
- if (hostdata->sensing) {
+ if (hostdata->sensing == cmd) {
scsi_eh_restore_cmnd(cmd, &hostdata->ses);
list_add(&ncmd->list, &hostdata->autosense);
hostdata->sensing = NULL;