From patchwork Tue Sep 26 07:15:24 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Giulio Benetti X-Patchwork-Id: 726954 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 980BBE7D242 for ; Tue, 26 Sep 2023 07:16:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229738AbjIZHQi (ORCPT ); Tue, 26 Sep 2023 03:16:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41264 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232317AbjIZHQh (ORCPT ); Tue, 26 Sep 2023 03:16:37 -0400 X-Greylist: delayed 60 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Tue, 26 Sep 2023 00:16:30 PDT Received: from smtpcmd01-g.aruba.it (smtpcmd01-g.aruba.it [62.149.158.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5227AFF for ; Tue, 26 Sep 2023 00:16:30 -0700 (PDT) Received: from localhost.localdomain ([146.241.127.78]) by Aruba Outgoing Smtp with ESMTPSA id l2I2qCEHD4eZZl2I2qUW84; Tue, 26 Sep 2023 09:15:26 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=aruba.it; s=a1; t=1695712526; bh=OExhW2DgjmeiaHG/jb9dsLA8Whjyqh4y9yQrv2YMLzM=; h=From:To:Subject:Date:MIME-Version:Content-Type; b=emjADryJhcpQhTfxQXFpNIzrSALOlGS1EA1LjZSb2N0BNJ44YY9NgHvHl+ugc8ZId 0lSLLTIRDDUQghnJriovPtHXBVpfn2y/u61x8j21gS4WHFsrxJFVtFqmKBoqbFXlO6 U7voT+2q+HZSZ7XThie2c1K7vRgAJKbZfUOc39LPt5jaj66SgZuZMD7dOnU+a1Id6V AYUBertD846f3Soz8ET1eOhfp5KY0vNvs2kpJN3JmymTym9Kr784Qyin0rkpTSrntn G+6yIxhi2oaWJ7BmHNuc3EEgL095E9ICaUzqbS4NlZ8+hYbZ+XtJ5NRSHvUpKD5LqI MdksTP//e6Fgg== From: Giulio Benetti To: linux-mmc@vger.kernel.org Cc: Giulio Benetti Subject: [PATCH] mmc-utils: fix potential overflow Date: Tue, 26 Sep 2023 09:15:24 +0200 Message-Id: <20230926071524.3638706-1-giulio.benetti@benettiengineering.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 X-CMAE-Envelope: MS4xfAFl05mLTrFUCtBOy7psjaOOqlCxS8AR0owtY/CsCQM0wsIgpo49h+79I5mYz4k3ODwnC+xUa+rqR0HQ2J3Zi0L7YdOtfQbWcok0SdPnJkyyp1H3fQ6c H6HHip0Mtu2GvifsBZsyowLhUgVvEBNRkUnfxewntcAtEFoIFFZzeJPE+CMRhHEAd/zq3batuDghUHasrCGYmDI8oLwKqfs5V/P8ZxicnEsiXNV4kfJKIctr 3id21rLAV8TWZ0fCWvbo2Nc9zA0t+zPX+4LoUO6KN4s57wzrvvSNq2cSoEfAE59r Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org With fortify enabled gcc throws following error: from mmc_cmds.c:20: In function ‘read’, inlined from ‘do_rpmb_write_key’ at mmc_cmds.c:2233:8: /home/giuliobenetti/br_reproduce/a53922c5db3e605a5e81e53c034f45017ebb7db7/output/host/mipsel-buildroot-linux-gnu/sysroot/usr/include/bits/unistd.h:38:10: error: ‘__read_alias’ writing 228 or more bytes into a region of size 32 overflows the destination [-Werror=stringop-overflow=] 38 | return __glibc_fortify (read, __nbytes, sizeof (char), | ^~~~~~~~~~~~~~~ mmc_cmds.c: In function ‘do_rpmb_write_key’: mmc_cmds.c:2087:19: note: destination object ‘key_mac’ of size 32 2087 | u_int8_t key_mac[32]; | ^~~~~~~ /home/giuliobenetti/br_reproduce/a53922c5db3e605a5e81e53c034f45017ebb7db7/output/host/mipsel-buildroot-linux-gnu/sysroot/usr/include/bits/unistd.h:26:16: note: in a call to function ‘__read_alias’ declared with attribute ‘access (write_only, 2, 3)’ 26 | extern ssize_t __REDIRECT (__read_alias, (int __fd, void *__buf, | ^~~~~~~~~~ read() could potentially return more than nbyte so let's check for ret < nbyte. Signed-off-by: Giulio Benetti --- mmc_cmds.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mmc_cmds.c b/mmc_cmds.c index 10d063d..ae7b876 100644 --- a/mmc_cmds.c +++ b/mmc_cmds.c @@ -2065,7 +2065,7 @@ int do_sanitize(int nargs, char **argv) } \ else if (r > 0) \ ret += r; \ - } while (r != 0 && (size_t)ret != nbyte); \ + } while (r != 0 && (size_t)ret < nbyte); \ \ ret; \ })