From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D9A9FC4360F for ; Tue, 2 Apr 2019 13:45:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id ADD4A2133D for ; Tue, 2 Apr 2019 13:45:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732146AbfDBNpt (ORCPT ); Tue, 2 Apr 2019 09:45:49 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:43246 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731447AbfDBNkG (ORCPT ); Tue, 2 Apr 2019 09:40:06 -0400 Received: from [167.98.27.226] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1hBJdv-0002mn-4k; Tue, 02 Apr 2019 14:39:59 +0100 Received: from ben by deadeye with local (Exim 4.92) (envelope-from ) id 1hBJdu-0004rr-5u; Tue, 02 Apr 2019 14:39:58 +0100 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, Denis Kirjanov , "Greg Kroah-Hartman" , "Colin Ian King" Date: Tue, 02 Apr 2019 14:38:27 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 18/99] altera-stapl: check for a null key before strcasecmp'ing it In-Reply-To: X-SA-Exim-Connect-IP: 167.98.27.226 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 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.65-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Colin Ian King commit 9ccb645683ef46e3c52c12c088a368baa58447d4 upstream. Currently the null check on key is occurring after the strcasecmp on the key, hence there is a potential null pointer dereference on key. Fix this by checking if key is null first. Also replace the == 0 check on strcasecmp with just the ! operator. Detected by CoverityScan, CID#1248787 ("Dereference before null check") Fixes: fa766c9be58b ("[media] Altera FPGA firmware download module") Signed-off-by: Colin Ian King Signed-off-by: Greg Kroah-Hartman [bwh: Backported to 3.16: old code used strnicmp()] Signed-off-by: Ben Hutchings --- drivers/misc/altera-stapl/altera.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/misc/altera-stapl/altera.c b/drivers/misc/altera-stapl/altera.c index ef83a9078646..d2ed3b9728b7 100644 --- a/drivers/misc/altera-stapl/altera.c +++ b/drivers/misc/altera-stapl/altera.c @@ -2176,8 +2176,7 @@ static int altera_get_note(u8 *p, s32 program_size, key_ptr = &p[note_strings + get_unaligned_be32( &p[note_table + (8 * i)])]; - if ((strnicmp(key, key_ptr, strlen(key_ptr)) == 0) && - (key != NULL)) { + if (key && !strncasecmp(key, key_ptr, strlen(key_ptr))) { status = 0; value_ptr = &p[note_strings +