From patchwork Fri Jan 24 09:30:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 233179 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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 1AD2EC35242 for ; Fri, 24 Jan 2020 09:57:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DA1502075D for ; Fri, 24 Jan 2020 09:57:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579859847; bh=QQPiKeJZPSJfQLVk389FTKmzw5CvuQDkwyzYBflZ7tw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=nStb7ioNCifKbOB6pahT3Zmtie8PK1RjiNXAzeRVuajgbQmoac5k7EuykmDvhQZLC ZRV3QHoaP9oMCtuKqKSa7dqkLxRzyT7Jy2aq3vFPkzC6O3Se6ufy5ngOFyn1deXSbm mzCWDhXnHXs9Mbqpv84u39rKq9f3nKenuwksOXQA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731494AbgAXJ50 (ORCPT ); Fri, 24 Jan 2020 04:57:26 -0500 Received: from mail.kernel.org ([198.145.29.99]:33002 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730740AbgAXJ50 (ORCPT ); Fri, 24 Jan 2020 04:57:26 -0500 Received: from localhost (unknown [145.15.244.15]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9FF4F20709; Fri, 24 Jan 2020 09:57:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579859845; bh=QQPiKeJZPSJfQLVk389FTKmzw5CvuQDkwyzYBflZ7tw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kKlu/72yQNwX14k++MhKBZdEbvIY5+C7Owy9xwXQasc2RVcDWFRpfErv5ZPiVVNTQ hiOpqyTFeRyFjzBsQ76imV9aQVVquDN72z9AD0sR2532MQ6KnBfG6Y3HdI+0afv5J5 RAuKIJEIAewdEUGUD3HFscNrCAxgpMPnUaf0QFY8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Carpenter , Douglas Anderson , Daniel Thompson , Sasha Levin Subject: [PATCH 4.14 207/343] kdb: do a sanity check on the cpu in kdb_per_cpu() Date: Fri, 24 Jan 2020 10:30:25 +0100 Message-Id: <20200124092947.325355495@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200124092919.490687572@linuxfoundation.org> References: <20200124092919.490687572@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Dan Carpenter [ Upstream commit b586627e10f57ee3aa8f0cfab0d6f7dc4ae63760 ] The "whichcpu" comes from argv[3]. The cpu_online() macro looks up the cpu in a bitmap of online cpus, but if the value is too high then it could read beyond the end of the bitmap and possibly Oops. Fixes: 5d5314d6795f ("kdb: core for kgdb back end (1 of 2)") Signed-off-by: Dan Carpenter Reviewed-by: Douglas Anderson Signed-off-by: Daniel Thompson Signed-off-by: Sasha Levin --- kernel/debug/kdb/kdb_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index 993db6b2348e7..15d902daeef6c 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -2634,7 +2634,7 @@ static int kdb_per_cpu(int argc, const char **argv) diag = kdbgetularg(argv[3], &whichcpu); if (diag) return diag; - if (!cpu_online(whichcpu)) { + if (whichcpu >= nr_cpu_ids || !cpu_online(whichcpu)) { kdb_printf("cpu %ld is not online\n", whichcpu); return KDB_BADCPUNUM; }