From patchwork Tue Nov 12 13:29:38 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?TWFyay1QSyBUc2FpICjolKHmspvliZsp?= X-Patchwork-Id: 11239311 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DD4C114E5 for ; Tue, 12 Nov 2019 13:31:22 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BA28121A49 for ; Tue, 12 Nov 2019 13:31:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="esZ79em+"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=mediatek.com header.i=@mediatek.com header.b="l/h8OgTb" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BA28121A49 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=mediatek.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mediatek-bounces+patchwork-linux-mediatek=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-ID:Date:Subject:To :From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=M01YHk8irRi4mvsvZwu3buJ+gCAgQx72RUCJV1imiyE=; b=esZ79em+napexl lDStaXzFlJrK4gfs1LLEen5cJnAvYmZZdyAJLK67KkE+b1GPNOU8Jx4HEotm6j+sOxNRqDKfs2fY+ X2vl+2ACV2WIrOKWcZFqLUZiSYmMBuUuTVI5050EThwAmjLl/l63z6lEpma1yr+IGQ8p5nROcaO3l 0ADyTDuedRlI8Do9/5DCqWfwhk1DhHsW2R2h4kyxgX5E7tYTCGvXY3OWi2H4QvD7dtu1sjG/+xsIu mzxvRx34zRXrAqdS60T9KJB6LB4ciqE8m2YHsC4Mmqph2qLf4gYlv6NzwBTPW5ru381US6t3mU4hj lv6PpAkB3/gzh/zJ+Emg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iUWGN-0007Ym-BF; Tue, 12 Nov 2019 13:31:19 +0000 Received: from mailgw01.mediatek.com ([216.200.240.184]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iUWGF-0007Qv-1q; Tue, 12 Nov 2019 13:31:12 +0000 X-UUID: 6a700a19ae2546f4a36bbe1c9aad8a50-20191112 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Transfer-Encoding:Content-Type:MIME-Version:Message-ID:Date:Subject:CC:To:From; bh=hT9QBdG+LtUKaBpt4OHfKg/vmDyoLlBwacPEIY+C38w=; b=l/h8OgTbd9GX8WRcOrFoOu5PNXuzU9akznAB+2X9v2vhclOHI9JXoWV22TJ2xaskjLvfXHqDOvFOha6ZswtjU59oB6GJh6f7GDMPSp1nD/0RQZCMZ13ZIdpChBvf1tyNva4W7ugamIWh8uZOj1w8SV4/VNqGUjqWuIflcZddpZQ=; X-UUID: 6a700a19ae2546f4a36bbe1c9aad8a50-20191112 Received: from mtkcas66.mediatek.inc [(172.29.193.44)] by mailgw01.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLS) with ESMTP id 1381528894; Tue, 12 Nov 2019 05:31:04 -0800 Received: from MTKMBS06N2.mediatek.inc (172.21.101.130) by MTKMBS62DR.mediatek.inc (172.29.94.18) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Tue, 12 Nov 2019 05:31:02 -0800 Received: from mtkcas07.mediatek.inc (172.21.101.84) by mtkmbs06n2.mediatek.inc (172.21.101.130) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Tue, 12 Nov 2019 21:31:00 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkcas07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Tue, 12 Nov 2019 21:31:00 +0800 From: Mark-PK Tsai To: Subject: [PATCH] ARM: fix race in for_each_frame Date: Tue, 12 Nov 2019 21:29:38 +0800 Message-ID: <20191112132937.19335-1-mark-pk.tsai@mediatek.com> X-Mailer: git-send-email 2.18.0 MIME-Version: 1.0 X-TM-SNTS-SMTP: 323926A5FB2DE832EA31753876BD697D6E80BA9E1623AE50FC1C3E17F6D5373C2000:8 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191112_053111_102990_A72ABDFB X-CRM114-Status: UNSURE ( 8.46 ) X-CRM114-Notice: Please train this message. X-Spam-Score: -0.2 (/) X-Spam-Report: SpamAssassin version 3.4.2 on bombadil.infradead.org summary: Content analysis details: (-0.2 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at https://www.dnswl.org/, no trust [216.200.240.184 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record 0.0 MIME_BASE64_TEXT RAW: Message text disguised using base64 encoding -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid 0.0 UNPARSEABLE_RELAY Informational: message has unparseable relay lines X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kstewart@linuxfoundation.org, mike-sl.lin@mediatek.com, alix.wu@mediatek.com, eddy.lin@mediatek.com, gregkh@linuxfoundation.org, yj.chiang@mediatek.com, phil.chang@mediatek.com, linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-arm-kernel@lists.infradead.org, mark-pk.tsai@mediatek.com, matthias.bgg@gmail.com, tglx@linutronix.de, info@metux.net, lvqiang.huang@unisoc.com, allison@lohutok.net Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+patchwork-linux-mediatek=patchwork.kernel.org@lists.infradead.org The sv_pc, which is saved in the stack, may be an invalid address if the target thread is running on another processor in the meantime. It will cause kernel crash at `ldr r2, [sv_pc, #-4]`. Check if sv_pc is valid before use it like unwind_frame in arch/arm/kernel/unwind.c. Signed-off-by: Mike-SL Lin Signed-off-by: Mark-PK Tsai --- arch/arm/lib/backtrace.S | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/arm/lib/backtrace.S b/arch/arm/lib/backtrace.S index 582925238d65..84f06381bbfb 100644 --- a/arch/arm/lib/backtrace.S +++ b/arch/arm/lib/backtrace.S @@ -64,6 +64,11 @@ for_each_frame: tst frame, mask @ Check for address exceptions sub sv_pc, sv_pc, offset @ Correct PC for prefetching bic sv_pc, sv_pc, mask @ mask PC/LR for the mode + mov r0, sv_pc + bl kernel_text_address @ check if sv_pc is valid + cmp r0, #0 @ if sv_pc is not kernel text + beq 1006f @ address, abort backtrace + 1003: ldr r2, [sv_pc, #-4] @ if stmfd sp!, {args} exists, ldr r3, .Ldsi+4 @ adjust saved 'pc' back one teq r3, r2, lsr #11 @ instruction