From patchwork Wed Mar 20 14:51:27 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrey Konovalov X-Patchwork-Id: 10861997 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B2E7F14DE for ; Wed, 20 Mar 2019 14:54:04 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A0E1029D86 for ; Wed, 20 Mar 2019 14:54:04 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9E91229DA5; Wed, 20 Mar 2019 14:54:04 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.5 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, USER_IN_DEF_DKIM_WL autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2C89C29D86 for ; Wed, 20 Mar 2019 14:54:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728597AbfCTOw2 (ORCPT ); Wed, 20 Mar 2019 10:52:28 -0400 Received: from mail-qt1-f201.google.com ([209.85.160.201]:42504 "EHLO mail-qt1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728590AbfCTOw1 (ORCPT ); Wed, 20 Mar 2019 10:52:27 -0400 Received: by mail-qt1-f201.google.com with SMTP id n10so2670562qtk.9 for ; Wed, 20 Mar 2019 07:52:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=BhVJ8uqyuZN/RhYo8e4D2Wo6j82d4Ue7nF7755mNwHM=; b=JN7peWS7Nez+2uGYBenvD1URtgpAIqAee70ib/k/sIrShjHTRTOTS60cMewca4/dl+ dG9NPJL3RBHz+jByCPy9VsQpiotQxDiag9Y5aB1mow2uCgebTPUHJtgOnmaSI9Vr/YIx hQI/v/gR0GvyO5deZUXNGQI2iRQRxhpRf4qspE3jPUxJjXOAuD/wl6/iqPcyOgYmtLKK MWpwP9BARDOkmKwS67XX82wJzNDDELNK9gdSeTBhBvMrWdTjib0F+nJEJKUwKFoB/pDB SXeryLoUidHqjz93zv8BQ7DsI9WVz5TfwJy9iV6N2sA8iMykCz2Q8F38PNgxFh8B+8WB 8apg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=BhVJ8uqyuZN/RhYo8e4D2Wo6j82d4Ue7nF7755mNwHM=; b=e9Tp910NzONY4EIbUMQqxEDqjaP9flvUEq73iY5oDafHrBJ5MZcJmiMvrw9slwBeln IMeD/tM+BF7easeVcNG9jE+QIKasSw6BMRR01up/3nss9Vhvmbhc3C69kmOC+t75HhZ2 QSDq7ZDR55x5ELs0cVlSzLhaR01WhuAjSCDANspWU4+CX5tZBwsmtAREoDwzkb92qple beF+YmQR3vGwzMJwdPvwEdvSkuUEvXe8Wh0N3PrgU7tFzbyUGYygVSpj3D4FGonKye3j b3tfiiQ0MRiJAZUG9l1tqgJKykqFEoC5guIXXkuVK/NZCo2BdlDBkVlstQJpGzO1mHFE kcEg== X-Gm-Message-State: APjAAAWiBw2shNk2ffjznU1zy20IEW+3rOaz/Ga55qOXZ5ey6IcC/kJx UnTASsnhNuaphq8/cXz9UPGuWbr/wup6BqjP X-Google-Smtp-Source: APXvYqwzO9qScb+3DLKygLOG3z91c2IWDiaev09n3TsGmqkOq4NcQ5CsSt3t0f+AffnIIDyplmnedU704klPsHau X-Received: by 2002:a05:620a:15fa:: with SMTP id p26mr919440qkm.51.1553093546857; Wed, 20 Mar 2019 07:52:26 -0700 (PDT) Date: Wed, 20 Mar 2019 15:51:27 +0100 In-Reply-To: Message-Id: <09d6b8e5c8275de85c7aba716578fbcb3cbce924.1553093421.git.andreyknvl@google.com> Mime-Version: 1.0 References: X-Mailer: git-send-email 2.21.0.225.g810b269d1ac-goog Subject: [PATCH v13 13/20] bpf, arm64: untag user pointers in stack_map_get_build_id_offset From: Andrey Konovalov To: Catalin Marinas , Will Deacon , Mark Rutland , Robin Murphy , Kees Cook , Kate Stewart , Greg Kroah-Hartman , Andrew Morton , Ingo Molnar , "Kirill A . Shutemov" , Shuah Khan , Vincenzo Frascino , Eric Dumazet , "David S. Miller" , Alexei Starovoitov , Daniel Borkmann , Steven Rostedt , Ingo Molnar , Peter Zijlstra , Arnaldo Carvalho de Melo , Alex Deucher , " =?utf-8?q?Christian_K=C3=B6nig?= " , "David (ChunMing) Zhou" , Yishai Hadas , Mauro Carvalho Chehab , Jens Wiklander , Alex Williamson , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-rdma@vger.kernel.org, linux-media@vger.kernel.org, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Dmitry Vyukov , Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Chintan Pandya , Luc Van Oostenryck , Dave Martin , Kevin Brodsky , Szabolcs Nagy , Andrey Konovalov Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch is a part of a series that extends arm64 kernel ABI to allow to pass tagged user pointers (with the top byte set to something else other than 0x00) as syscall arguments. stack_map_get_build_id_offset() uses provided user pointers for vma lookups, which can only by done with untagged pointers. Untag user pointers in this function for doing the lookup and calculating the offset, but save as is in the bpf_stack_build_id struct. Signed-off-by: Andrey Konovalov --- kernel/bpf/stackmap.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c index 950ab2f28922..bb89341d3faf 100644 --- a/kernel/bpf/stackmap.c +++ b/kernel/bpf/stackmap.c @@ -320,7 +320,9 @@ static void stack_map_get_build_id_offset(struct bpf_stack_build_id *id_offs, } for (i = 0; i < trace_nr; i++) { - vma = find_vma(current->mm, ips[i]); + u64 untagged_ip = untagged_addr(ips[i]); + + vma = find_vma(current->mm, untagged_ip); if (!vma || stack_map_get_build_id(vma, id_offs[i].build_id)) { /* per entry fall back to ips */ id_offs[i].status = BPF_STACK_BUILD_ID_IP; @@ -328,7 +330,7 @@ static void stack_map_get_build_id_offset(struct bpf_stack_build_id *id_offs, memset(id_offs[i].build_id, 0, BPF_BUILD_ID_SIZE); continue; } - id_offs[i].offset = (vma->vm_pgoff << PAGE_SHIFT) + ips[i] + id_offs[i].offset = (vma->vm_pgoff << PAGE_SHIFT) + untagged_ip - vma->vm_start; id_offs[i].status = BPF_STACK_BUILD_ID_VALID; }