From 919f797a4c9c22ff5ec059744dba364dc600ece2 Mon Sep 17 00:00:00 2001 From: "Martin K. Petersen" Date: Sat, 14 Apr 2012 23:01:28 -0400 Subject: [PATCH] SCSI: Fix error handling when no ULD is attached Commit 18a4d0a22ed6 ("[SCSI] Handle disk devices which can not process medium access commands") introduced a bug in which we would attempt to dereference the scsi driver even when the device had no ULD attached. Ensure that a driver is registered and make the driver accessor function more resilient to errors during device discovery. Reported-by: Elric Fu Reported-by: Bart Van Assche Signed-off-by: Martin K. Petersen Signed-off-by: Linus Torvalds --- drivers/scsi/scsi_error.c | 2 +- include/scsi/scsi_cmnd.h | 3 +++ 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c index 2cfcbffa41fd..386f0c53bea7 100644 --- a/drivers/scsi/scsi_error.c +++ b/drivers/scsi/scsi_error.c @@ -835,7 +835,7 @@ static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, unsigned char *cmnd, scsi_eh_restore_cmnd(scmd, &ses); - if (sdrv->eh_action) + if (sdrv && sdrv->eh_action) rtn = sdrv->eh_action(scmd, cmnd, cmnd_size, rtn); return rtn; diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h index 377df4a28512..1e1198546c72 100644 --- a/include/scsi/scsi_cmnd.h +++ b/include/scsi/scsi_cmnd.h @@ -134,6 +134,9 @@ struct scsi_cmnd { static inline struct scsi_driver *scsi_cmd_to_driver(struct scsi_cmnd *cmd) { + if (!cmd->request->rq_disk) + return NULL; + return *(struct scsi_driver **)cmd->request->rq_disk->private_data; }