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=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 2E36EC28CC1 for ; Sat, 1 Jun 2019 13:27:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EE98D273D5 for ; Sat, 1 Jun 2019 13:27:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559395632; bh=8dJthh1jYsngYIJ74T3O79DJE0/Xj/gr+R9BWBUL8gI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=DhqCrB/Gghh1bpXFhp8bO8SqBt9Ys0jZ58ldQxydrIxeCt55NzEFbjp6kNmgKG35Z LEIaknxEcij644N8Gd2wtoDxt3kTyQ+s9iEgJhbmZ+1cz/LSmAZbaT9PoppBfELSrs 6QIB+QZ6e3HyquDE94lXjHUH9f/gh16Vl3Wp4M7Y= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729563AbfFAN1K (ORCPT ); Sat, 1 Jun 2019 09:27:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:57704 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728169AbfFAN1G (ORCPT ); Sat, 1 Jun 2019 09:27:06 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1F68E273CB; Sat, 1 Jun 2019 13:27:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559395625; bh=8dJthh1jYsngYIJ74T3O79DJE0/Xj/gr+R9BWBUL8gI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LYWQApqnLTC9qgr+xT2ocmHVtgLxAz9de3iN/SXsm+NfU01/VNcHVytZtQoDnNmft IdKf0dzUWlSqAg2Ux7pnozO1L4Is1zugq2SEd/FS+v35+vdJ69UEeTGEzrSscGjAAw GYejvMfDwACv8Lr1EgSeDQ0Hr3whOdv44Btkm8+s= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Yufen Yu , Xiao Ni , NeilBrown , Song Liu , Sasha Levin , linux-raid@vger.kernel.org Subject: [PATCH AUTOSEL 4.4 38/56] md: add mddev->pers to avoid potential NULL pointer dereference Date: Sat, 1 Jun 2019 09:25:42 -0400 Message-Id: <20190601132600.27427-38-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190601132600.27427-1-sashal@kernel.org> References: <20190601132600.27427-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Yufen Yu [ Upstream commit ee37e62191a59d253fc916b9fc763deb777211e2 ] When doing re-add, we need to ensure rdev->mddev->pers is not NULL, which can avoid potential NULL pointer derefence in fallowing add_bound_rdev(). Fixes: a6da4ef85cef ("md: re-add a failed disk") Cc: Xiao Ni Cc: NeilBrown Cc: # 4.4+ Reviewed-by: NeilBrown Signed-off-by: Yufen Yu Signed-off-by: Song Liu Signed-off-by: Sasha Levin --- drivers/md/md.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 07f307402351b..f71cca28dddac 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -2690,8 +2690,10 @@ state_store(struct md_rdev *rdev, const char *buf, size_t len) err = 0; } } else if (cmd_match(buf, "re-add")) { - if (test_bit(Faulty, &rdev->flags) && (rdev->raid_disk == -1) && - rdev->saved_raid_disk >= 0) { + if (!rdev->mddev->pers) + err = -EINVAL; + else if (test_bit(Faulty, &rdev->flags) && (rdev->raid_disk == -1) && + rdev->saved_raid_disk >= 0) { /* clear_bit is performed _after_ all the devices * have their local Faulty bit cleared. If any writes * happen in the meantime in the local node, they -- 2.20.1