From patchwork Tue Jul 31 13:46:01 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johannes Thumshirn X-Patchwork-Id: 10550807 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 55BE914E2 for ; Tue, 31 Jul 2018 13:48:31 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 41F2F2ADF7 for ; Tue, 31 Jul 2018 13:48:31 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 35CB82AE06; Tue, 31 Jul 2018 13:48:31 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D8D472ADF7 for ; Tue, 31 Jul 2018 13:48:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732380AbeGaP2s (ORCPT ); Tue, 31 Jul 2018 11:28:48 -0400 Received: from mx2.suse.de ([195.135.220.15]:41916 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1732378AbeGaP2h (ORCPT ); Tue, 31 Jul 2018 11:28:37 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 25B20AE1B; Tue, 31 Jul 2018 13:48:12 +0000 (UTC) From: Johannes Thumshirn To: "Martin K . Petersen" Cc: Linux Kernel Mailinglist , Linux SCSI Mailinglist , ard , Johannes Thumshirn Subject: [PATCH 1/3] fcoe: fix use-after-free in fcoe_ctlr_els_send Date: Tue, 31 Jul 2018 15:46:01 +0200 Message-Id: <20180731134603.20089-2-jthumshirn@suse.de> X-Mailer: git-send-email 2.16.4 In-Reply-To: <20180731134603.20089-1-jthumshirn@suse.de> References: <20180731134603.20089-1-jthumshirn@suse.de> Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP KASAN reports a use-after-free in fcoe_ctlr_els_send() when we're sending a LOGO and have FIP debugging enabled. This is because we're first freeing the skb and then printing the frame's DID. But the DID is a member of the FC frame header which in turn is the skb's payload. Exchange the debug print and kfree_skb() calls so we're not touching the freed data. Signed-off-by: Johannes Thumshirn Reviewed-by: Hannes Reinecke --- drivers/scsi/fcoe/fcoe_ctlr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/fcoe/fcoe_ctlr.c b/drivers/scsi/fcoe/fcoe_ctlr.c index ea23c8dffc25..ceb35ebbeb8f 100644 --- a/drivers/scsi/fcoe/fcoe_ctlr.c +++ b/drivers/scsi/fcoe/fcoe_ctlr.c @@ -799,9 +799,9 @@ int fcoe_ctlr_els_send(struct fcoe_ctlr *fip, struct fc_lport *lport, fip->send(fip, skb); return -EINPROGRESS; drop: - kfree_skb(skb); LIBFCOE_FIP_DBG(fip, "drop els_send op %u d_id %x\n", op, ntoh24(fh->fh_d_id)); + kfree_skb(skb); return -EINVAL; } EXPORT_SYMBOL(fcoe_ctlr_els_send);