scsi: core: Avoid that ATA error handling can trigger a kernel hang or oops
Avoid that the recently introduced call_rcu() call in the SCSI core
triggers a double call_rcu() call.
Reported-by: Natanael Copa <ncopa@alpinelinux.org>
Reported-by: Damien Le Moal <damien.lemoal@wdc.com>
References: https://bugzilla.kernel.org/show_bug.cgi?id=198861
Fixes: 3bd6f43f5cb3 ("scsi: core: Ensure that the SCSI error handler gets woken up")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Tested-by: Damien Le Moal <damien.lemoal@wdc.com>
Cc: Natanael Copa <ncopa@alpinelinux.org>
Cc: Damien Le Moal <damien.lemoal@wdc.com>
Cc: Alexandre Oliva <oliva@gnu.org>
Cc: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c
index d042915..ca53a5f 100644
--- a/drivers/scsi/scsi_error.c
+++ b/drivers/scsi/scsi_error.c
@@ -223,7 +223,8 @@ static void scsi_eh_reset(struct scsi_cmnd *scmd)
static void scsi_eh_inc_host_failed(struct rcu_head *head)
{
- struct Scsi_Host *shost = container_of(head, typeof(*shost), rcu);
+ struct scsi_cmnd *scmd = container_of(head, typeof(*scmd), rcu);
+ struct Scsi_Host *shost = scmd->device->host;
unsigned long flags;
spin_lock_irqsave(shost->host_lock, flags);
@@ -259,7 +260,7 @@ void scsi_eh_scmd_add(struct scsi_cmnd *scmd)
* Ensure that all tasks observe the host state change before the
* host_failed change.
*/
- call_rcu(&shost->rcu, scsi_eh_inc_host_failed);
+ call_rcu(&scmd->rcu, scsi_eh_inc_host_failed);
}
/**