scsi: sg: don't return bogus Sg_requests
If the list search in sg_get_rq_mark() fails to find a valid request, we
return a bogus element. This then can later lead to a GPF in
sg_remove_scat().
So don't return bogus Sg_requests in sg_get_rq_mark() but NULL in case
the list search doesn't find a valid request.
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Doug Gilbert <dgilbert@interlog.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Doug Gilbert <dgilbert@interlog.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 0a38ba0..82c33a6 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -2074,11 +2074,12 @@ sg_get_rq_mark(Sg_fd * sfp, int pack_id)
if ((1 == resp->done) && (!resp->sg_io_owned) &&
((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
resp->done = 2; /* guard against other readers */
- break;
+ write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
+ return resp;
}
}
write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
- return resp;
+ return NULL;
}
/* always adds to end of list */