From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757524AbaFYPwm (ORCPT ); Wed, 25 Jun 2014 11:52:42 -0400 Received: from zimbra13.linbit.com ([212.69.166.240]:45934 "EHLO zimbra13.linbit.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757441AbaFYPwl (ORCPT ); Wed, 25 Jun 2014 11:52:41 -0400 From: Philipp Reisner To: linux-kernel@vger.kernel.org, Jens Axboe Cc: drbd-dev@lists.linbit.com Subject: [PATCH] drbd: fix NULL pointer deref in blk_add_request_payload Date: Wed, 25 Jun 2014 17:52:38 +0200 Message-Id: <1403711558-27267-2-git-send-email-philipp.reisner@linbit.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1403711558-27267-1-git-send-email-philipp.reisner@linbit.com> References: <1403711558-27267-1-git-send-email-philipp.reisner@linbit.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Lars Ellenberg Discards don't have any payload. But the scsi layer still expects a bio_vec it can use internally, see sd_setup_discard_cmnd() and blk_add_request_payload(). Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg --- drivers/block/drbd/drbd_receiver.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c index b6c8aaf..5b17ec8 100644 --- a/drivers/block/drbd/drbd_receiver.c +++ b/drivers/block/drbd/drbd_receiver.c @@ -1337,8 +1337,11 @@ int drbd_submit_peer_request(struct drbd_device *device, return 0; } + /* Discards don't have any payload. + * But the scsi layer still expects a bio_vec it can use internally, + * see sd_setup_discard_cmnd() and blk_add_request_payload(). */ if (peer_req->flags & EE_IS_TRIM) - nr_pages = 0; /* discards don't have any payload. */ + nr_pages = 1; /* In most cases, we will only need one bio. But in case the lower * level restrictions happen to be different at this offset on this -- 1.9.1