From patchwork Mon Aug 3 15:39:53 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miles Chen X-Patchwork-Id: 11698351 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 7C60713B6 for ; Mon, 3 Aug 2020 15:40:31 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 54BC720578 for ; Mon, 3 Aug 2020 15:40:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="u0M+C4tD"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=mediatek.com header.i=@mediatek.com header.b="FSH/bkb0" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 54BC720578 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-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.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=ZH4vkIIi/yWU+hXcBY7Dtc9WhUi+PAYY+kN6R7H7LdE=; b=u0M+C4tDg4Pi851RqZUL5w+Zth QdRbGj+xispsYtuWCd/lU4hZyoEgwKKulefgajDtU2jbtJfE7whWdM1PYWFswbpbcUzf2Mh3us9U9 wM2u/l6Xd4QKyWkv5Dh1E8f0uZOzgzNWwTGr19PBfsHB+MoizObVWNXtlF5wr0POl6ZgM1pwBrPde AYoIPNy/8yDjBPyDwwlvigHYBPcZlPAqIom2ZQtko6exiQlI0S2yD4TcHx/G0eXY+o98VWsKCufWZ ZpqVdcSAjG3E6NjfOUa1H9t7OUXE4PrxgjTf2KWsz0aN+FcxZvHC5RNBDZSPqzTLPU7uBrthGkhJg Y0mCOqmg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1k2cZZ-0002s1-P7; Mon, 03 Aug 2020 15:40:21 +0000 Received: from mailgw01.mediatek.com ([216.200.240.184]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1k2cZX-0002q4-0T; Mon, 03 Aug 2020 15:40:20 +0000 X-UUID: 73c3fc968597484ea789302eaa73063f-20200803 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=+W1pY9M613RDdoabjfIUPYlQHHrDntAsNM3ob88BJcY=; b=FSH/bkb0al/Q/U1KFmTzV8wUdTYCVrIFH7gtZ7abVZnGk1OH2iU5JXPWo3D45OfR9EfJ/em7Sg+A8NrMUaYD2ifpwikz8f7hETR0acvjj5jl7gI5VolLwwugouvnTjJ5tRRelkbfOb/1P33PRPNldattyA+wX5fGhNC1TjWbOf4=; X-UUID: 73c3fc968597484ea789302eaa73063f-20200803 Received: from mtkcas68.mediatek.inc [(172.29.94.19)] by mailgw01.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLS) with ESMTP id 1113573135; Mon, 03 Aug 2020 07:40:02 -0800 Received: from mtkmbs08n1.mediatek.inc (172.21.101.55) by MTKMBS62N1.mediatek.inc (172.29.193.41) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Mon, 3 Aug 2020 08:40:04 -0700 Received: from mtkcas07.mediatek.inc (172.21.101.84) by mtkmbs08n1.mediatek.inc (172.21.101.55) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Mon, 3 Aug 2020 23:39:50 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkcas07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Mon, 3 Aug 2020 23:39:52 +0800 From: Miles Chen To: Alexey Dobriyan Subject: [PATCH] proc: use untagged_addr() for pagemap_read addresses Date: Mon, 3 Aug 2020 23:39:53 +0800 Message-ID: <20200803153953.20364-1-miles.chen@mediatek.com> X-Mailer: git-send-email 2.18.0 MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200803_114019_180771_776C1F91 X-CRM114-Status: GOOD ( 13.70 ) X-Spam-Score: -0.2 (/) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-0.2 points) pts rule name description ---- ---------------------- -------------------------------------------------- 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record 0.0 MIME_BASE64_TEXT RAW: Message text disguised using base64 encoding -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain 0.0 UNPARSEABLE_RELAY Informational: message has unparseable relay lines X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: wsd_upstream@mediatek.com, linux-kernel@vger.kernel.org, Miles Chen , linux-mediatek@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org When we try to visit the pagemap of a tagged userspace pointer, we find that the start_vaddr is not correct because of the tag. To fix it, we should untag the usespace pointers in pagemap_read(). Signed-off-by: Miles Chen --- fs/proc/task_mmu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index dbda4499a859..d0c6e8e0cf37 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -1541,11 +1541,11 @@ static ssize_t pagemap_read(struct file *file, char __user *buf, src = *ppos; svpfn = src / PM_ENTRY_BYTES; - start_vaddr = svpfn << PAGE_SHIFT; + start_vaddr = untagged_addr(svpfn << PAGE_SHIFT); end_vaddr = mm->task_size; /* watch out for wraparound */ - if (svpfn > mm->task_size >> PAGE_SHIFT) + if (start_vaddr > mm->task_size) start_vaddr = end_vaddr; /*