From c68bf8eeaa57c852e74adcf597237be149eef830 Mon Sep 17 00:00:00 2001
From: Petr Uzel <petr.uzel@suse.cz>
Date: Fri, 21 Oct 2011 13:31:09 +0200
Subject: [PATCH] [SCSI] st: fix race in st_scsi_execute_end
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

The call to complete() in st_scsi_execute_end() wakes up sleeping thread
in write_behind_check(), which frees the st_request, thus invalidating
the pointer to the associated bio structure, which is then passed to the
blk_rq_unmap_user(). Fix by storing pointer to bio structure into
temporary local variable.

This bug is present since at least linux-2.6.32.

CC: stable@kernel.org
Signed-off-by: Petr Uzel <petr.uzel@suse.cz>
Reported-by: Juergen Groß <juergen.gross@ts.fujitsu.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Kai Mäkisara <kai.makisara@kolumbus.fi>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
---
Reading git-format-patch failed