From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932103AbbHBAm3 (ORCPT ); Sat, 1 Aug 2015 20:42:29 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:36726 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752109AbbHBAdH (ORCPT ); Sat, 1 Aug 2015 20:33:07 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "James Bottomley" , "Long Li" , "K. Y. Srinivasan" Date: Sun, 02 Aug 2015 01:02:37 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 031/164] scsi: storvsc: Fix a bug in copy_from_bounce_buffer() In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.249 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.70-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: "K. Y. Srinivasan" commit 8de580742fee8bc34d116f57a20b22b9a5f08403 upstream. We may exit this function without properly freeing up the maapings we may have acquired. Fix the bug. Signed-off-by: K. Y. Srinivasan Reviewed-by: Long Li Signed-off-by: James Bottomley [bwh: Backported to 3.2: - Adjust filename - Keep using kmap_atomic()/kunmap_atomic(), not the sg_-prefixed functions] Signed-off-by: Ben Hutchings --- drivers/staging/hv/storvsc_drv.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) --- a/drivers/staging/hv/storvsc_drv.c +++ b/drivers/staging/hv/storvsc_drv.c @@ -940,23 +940,24 @@ static unsigned int copy_to_bounce_buffe if (bounce_sgl[j].length == PAGE_SIZE) { /* full..move to next entry */ kunmap_atomic((void *)bounce_addr, KM_IRQ0); + bounce_addr = 0; j++; + } - /* if we need to use another bounce buffer */ - if (srclen || i != orig_sgl_count - 1) - bounce_addr = + /* if we need to use another bounce buffer */ + if (srclen && bounce_addr == 0) + bounce_addr = (unsigned long)kmap_atomic( sg_page((&bounce_sgl[j])), KM_IRQ0); - } else if (srclen == 0 && i == orig_sgl_count - 1) { - /* unmap the last bounce that is < PAGE_SIZE */ - kunmap_atomic((void *)bounce_addr, KM_IRQ0); - } } kunmap_atomic((void *)(src_addr - orig_sgl[i].offset), KM_IRQ0); } + if (bounce_addr) + kunmap_atomic((void *)bounce_addr, KM_IRQ0); + local_irq_restore(flags); return total_copied;