Commit 48ae8484 authored May 10, 2017 by Johannes Thumshirn Committed by Martin K. Petersen May 11, 2017

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>

parent ed44fd7f

drivers/scsi/sg.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -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 */