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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7F724C6FD1C for ; Wed, 22 Mar 2023 20:13:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232146AbjCVUNA (ORCPT ); Wed, 22 Mar 2023 16:13:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50936 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232171AbjCVUMd (ORCPT ); Wed, 22 Mar 2023 16:12:33 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 42F996C699; Wed, 22 Mar 2023 13:04:27 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id BF9AE622CD; Wed, 22 Mar 2023 20:03:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7DF60C4339B; Wed, 22 Mar 2023 20:03:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1679515392; bh=NxzOtRQu6KigYzzhwtqdp249Roma4xVFBm/yW7xDUEc=; h=From:To:Cc:Subject:Date:From; b=oGI8SywsJU30r5QhG2wnacLd5vOhYGV/2IBSymTv2IQJPpgu7fYdXnGPkzf4YT1LB 14EFG7ET5/YIOKYlsBS09CeR2ob+LlMHGkSONRyB5nUDJEUwRqUrEMfFbAt2MzFPxJ rlEmdSSB6vwZG0xdvhDXad4KQYsqiJ6JUxNoaXXnqTntjPL/tE6G0x8f7aAkqVKwFB S5S0zbIW97rMhhPWWaoL1eoCbMrfvqoAQFR9tvOptKn0UysVK+XqwkBUeRq/0ekzkp h7t9Cvpmuqc5x2xw6jwiVdFxZBJSzvSe2W1ZqjtJSCBl298zCoxCyuAdZIMaBcftKk MfnSRZCRSqeuw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: NeilBrown , Dan Carpenter , Song Liu , Sasha Levin , linux-raid@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 1/9] md: avoid signed overflow in slot_store() Date: Wed, 22 Mar 2023 16:03:01 -0400 Message-Id: <20230322200309.1997651-1-sashal@kernel.org> X-Mailer: git-send-email 2.39.2 MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: NeilBrown [ Upstream commit 3bc57292278a0b6ac4656cad94c14f2453344b57 ] slot_store() uses kstrtouint() to get a slot number, but stores the result in an "int" variable (by casting a pointer). This can result in a negative slot number if the unsigned int value is very large. A negative number means that the slot is empty, but setting a negative slot number this way will not remove the device from the array. I don't think this is a serious problem, but it could cause confusion and it is best to fix it. Reported-by: Dan Carpenter Signed-off-by: NeilBrown Signed-off-by: Song Liu Signed-off-by: Sasha Levin --- drivers/md/md.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/md/md.c b/drivers/md/md.c index 89d4dcc5253e5..f8c111b369928 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -2991,6 +2991,9 @@ slot_store(struct md_rdev *rdev, const char *buf, size_t len) err = kstrtouint(buf, 10, (unsigned int *)&slot); if (err < 0) return err; + if (slot < 0) + /* overflow */ + return -ENOSPC; } if (rdev->mddev->pers && slot == -1) { /* Setting 'slot' on an active array requires also -- 2.39.2