From patchwork Mon Mar 1 16:11:50 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 388648 Delivered-To: patch@linaro.org Received: by 2002:a02:290e:0:0:0:0:0 with SMTP id p14csp3496209jap; Mon, 1 Mar 2021 08:34:11 -0800 (PST) X-Google-Smtp-Source: ABdhPJwjuIlnmDpBAjpWdASR7doTKfdIqidQfcJHZ+z/7UP1zCai1mEGBICR6GLnl5pDBUMWV1mD X-Received: by 2002:aa7:c78e:: with SMTP id n14mr16984578eds.31.1614616451277; Mon, 01 Mar 2021 08:34:11 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1614616451; cv=none; d=google.com; s=arc-20160816; b=OVLXRRDLHtTx4Tmo6ThrLA8ARQsot3/0OZrYjVlrEBo42y01YfDYwmTx0vYM2P8y8e f4jgQ15iUeXW6Ds0vCMCMDN9Z8o8pMIksa2mlZfIrHH4xaAU5uOpYz9TKFGS+Fnjz79+ 0euoXs2dvRIQPBCA3aEdJ020CZxYyRS1/QO8YD3I6tRE4B1TgUyqvpM3egMkU05LdS/H MSQjctCPMQkI4E2B7vMNE9NdFmIrbScBxusyaeQqMAeZ76xSN0fmKMHTWIMQI1Xt852p IJH1bkdksuHI597W+JAOgEZCadzRx1EBWjaGdpHWU1z4UFVoCKwKM0hhXVBPEWvcFB+0 7MRg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:message-id:date:subject:cc:to :from:dkim-signature; bh=305gEp1g9nAFPu3aVeuZSMWjeC/iVInZ1vgmhYfShYI=; b=UKRpWe0YuV1X6sp5+15GRY79gtRh/9E06d5QvObe6iWzIdrO5qnldAI1OzlvFYABqb Sg1Hf+xTQwUx5O20MwnQ2z5ILzqCKeq3euaAYpes6XJdjBQM67rKQpWXwnw2g6TbxkCI pCPoFQjevB2cRsX4dzf1pG59GYCIIp/ezugY+qAx6OZEd8I3+oxZr14JecVODRg5WVmG WrSh8lZGwuhhCJlyH6Ss7YfJ7LlCWR/gPNCGeazW9Xi8qdNoxNfmjHakb4Rsm/It0vt3 0dzcusuCCOrVdvdfN0iLkWeaZy40B7iuVr7/mM/XK++pfQuAlb6czkLw6ve5DRlfsaZy yTgg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b=wLDfInZw; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id z15si12153661ejr.160.2021.03.01.08.34.10; Mon, 01 Mar 2021 08:34:11 -0800 (PST) Received-SPF: pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b=wLDfInZw; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232439AbhCAQbv (ORCPT + 13 others); Mon, 1 Mar 2021 11:31:51 -0500 Received: from mail.kernel.org ([198.145.29.99]:60756 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234546AbhCAQ06 (ORCPT ); Mon, 1 Mar 2021 11:26:58 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 4525764E12; Mon, 1 Mar 2021 16:22:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614615727; bh=iPXy742P8sRdpLi3cQoN84MtFgXqylTY+KqIjcXKuNM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wLDfInZwEVvHmx0Cp/lYxgFpgDSN3A25pgPx1vgrT1/6n6VRqheg6HoWbMRMkYhZP +95VPCmRtaTnqBvgBC6g5twLPk4b+KiWDYalLO9/0/vXzW8jAxs/ofdP7u9dB7oebi 9onmbxpdE2GCjAr22vTiYfTBPCUU+lHiLvxYWkDg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sumit Garg , Daniel Thompson Subject: [PATCH 4.9 009/134] kdb: Make memory allocations more robust Date: Mon, 1 Mar 2021 17:11:50 +0100 Message-Id: <20210301161014.036724218@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210301161013.585393984@linuxfoundation.org> References: <20210301161013.585393984@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Sumit Garg commit 93f7a6d818deef69d0ba652d46bae6fbabbf365c upstream. Currently kdb uses in_interrupt() to determine whether its library code has been called from the kgdb trap handler or from a saner calling context such as driver init. This approach is broken because in_interrupt() alone isn't able to determine kgdb trap handler entry from normal task context. This can happen during normal use of basic features such as breakpoints and can also be trivially reproduced using: echo g > /proc/sysrq-trigger We can improve this by adding check for in_dbg_master() instead which explicitly determines if we are running in debugger context. Cc: stable@vger.kernel.org Signed-off-by: Sumit Garg Link: https://lore.kernel.org/r/1611313556-4004-1-git-send-email-sumit.garg@linaro.org Signed-off-by: Daniel Thompson Signed-off-by: Greg Kroah-Hartman --- kernel/debug/kdb/kdb_private.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/debug/kdb/kdb_private.h +++ b/kernel/debug/kdb/kdb_private.h @@ -234,7 +234,7 @@ extern struct task_struct *kdb_curr_task #define kdb_do_each_thread(g, p) do_each_thread(g, p) #define kdb_while_each_thread(g, p) while_each_thread(g, p) -#define GFP_KDB (in_interrupt() ? GFP_ATOMIC : GFP_KERNEL) +#define GFP_KDB (in_dbg_master() ? GFP_ATOMIC : GFP_KERNEL) extern void *debug_kmalloc(size_t size, gfp_t flags); extern void debug_kfree(void *);