Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754841AbaDXIzx (ORCPT ); Thu, 24 Apr 2014 04:55:53 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:46976 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754813AbaDXIzs (ORCPT ); Thu, 24 Apr 2014 04:55:48 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Andy Grover , Nicholas Bellinger , Luis Henriques Subject: [PATCH 3.11 145/182] target/tcm_fc: Fix use-after-free of ft_tpg Date: Thu, 24 Apr 2014 09:51:10 +0100 Message-Id: <1398329507-5911-146-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1398329507-5911-1-git-send-email-luis.henriques@canonical.com> References: <1398329507-5911-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.11 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.11.10.9 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Andy Grover commit 2c42be2dd4f6586728dba5c4e197afd5cfaded78 upstream. ft_del_tpg checks tpg->tport is set before unlinking the tpg from the tport when the tpg is being removed. Set this pointer in ft_tport_create, or the unlinking won't happen in ft_del_tpg and tport->tpg will reference a deleted object. This patch sets tpg->tport in ft_tport_create, because that's what ft_del_tpg checks, and is the only way to get back to the tport to clear tport->tpg. The bug was occuring when: - lport created, tport (our per-lport, per-provider context) is allocated. tport->tpg = NULL - tpg created - a PRLI is received. ft_tport_create is called, tpg is found and tport->tpg is set - tpg removed. ft_tpg is freed in ft_del_tpg. Since tpg->tport was not set, tport->tpg is not cleared and points at freed memory - Future calls to ft_tport_create return tport via first conditional, instead of searching for new tpg by calling ft_lport_find_tpg. tport->tpg is still invalid, and will access freed memory. see https://bugzilla.redhat.com/show_bug.cgi?id=1071340 Signed-off-by: Andy Grover Signed-off-by: Nicholas Bellinger Signed-off-by: Luis Henriques --- drivers/target/tcm_fc/tfc_sess.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/target/tcm_fc/tfc_sess.c b/drivers/target/tcm_fc/tfc_sess.c index 4859505..639fdb3 100644 --- a/drivers/target/tcm_fc/tfc_sess.c +++ b/drivers/target/tcm_fc/tfc_sess.c @@ -68,6 +68,7 @@ static struct ft_tport *ft_tport_create(struct fc_lport *lport) if (tport) { tport->tpg = tpg; + tpg->tport = tport; return tport; } -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/