From patchwork Thu Jan 6 22:00:38 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Patrick Leis X-Patchwork-Id: 1576345 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: bilbo.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=google.com header.i=@google.com header.a=rsa-sha256 header.s=20210112 header.b=P/8tnCzn; dkim-atps=neutral Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by bilbo.ozlabs.org (Postfix) with ESMTPS id 4JVL7P5x6mz9sSs for ; Fri, 7 Jan 2022 09:07:28 +1100 (AEDT) Received: from localhost ([::1]:59966 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1n5auq-0001dB-C0 for incoming@patchwork.ozlabs.org; Thu, 06 Jan 2022 17:07:24 -0500 Received: from eggs.gnu.org ([209.51.188.92]:49552) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from <3imbXYQcKCskAt2896tv33v0t.r315t19-stAt0232v29.36v@flex--venture.bounces.google.com>) id 1n5auQ-0001cy-6P for qemu-devel@nongnu.org; Thu, 06 Jan 2022 17:06:58 -0500 Received: from [2607:f8b0:4864:20::b4a] (port=52895 helo=mail-yb1-xb4a.google.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from <3imbXYQcKCskAt2896tv33v0t.r315t19-stAt0232v29.36v@flex--venture.bounces.google.com>) id 1n5auO-0004IU-J8 for qemu-devel@nongnu.org; Thu, 06 Jan 2022 17:06:57 -0500 Received: by mail-yb1-xb4a.google.com with SMTP id u130-20020a254788000000b0060a9645f781so7612976yba.19 for ; Thu, 06 Jan 2022 14:06:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:message-id:mime-version:subject:from:to:cc; bh=5IlEkjJ+ofJj0s6IViJPQp6sFty9w8jzIZpJGSxhSHM=; b=P/8tnCznF5ncUi1FaT6Hl5/UTWqvO7VUfhc/bkpuNH5aZjTYBt9aJZ90LsIVS0TNRh sSwWUdAQe7UwDneyEX2SftJq3w/uV1yY8Dna8zhzApbHYokdY/N0QZrhGc0Jt6fNbJHK 6UKKkhWISex+cbbzYJYyUzOj+a0c028mgx9IfT3PaxkrYLT9yD3RUalt219TCoZWcscE 2n0kWDKvnCzufkGLuhjHzXuljNZcG7UqxuR8A5eF/NU/XfUpvkttDBblozDf/URCfyWj 9zegMiu6UWXqRwiTvOGunZ+xxT37InTs10ojXjHT7DdbZsOmQsX4BV3WsuOL7SaLBjdb dyOQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=5IlEkjJ+ofJj0s6IViJPQp6sFty9w8jzIZpJGSxhSHM=; b=CwNv4m5f6LeNZ8Hqf+PQVkG1JwG43Y+kZg2OERwAmwlwUfUXeWI8fG1ucvQQ4M8WPI LLgeh4kLiG4KCHdSZA/syag5bhx/lOD/L7JPvJldwF0iO/cWsZR2kcZPq6crzUhJ5b5l MkVl4eEUpSQYh1Y11ZXaJ6FUu42UVssBLa6ao14eJQMB0ffSST8QJwshD4djdhQOaJKh ff1v8+PfNx5N7QL0B49UurSi9u+NWzrsjOpMn2K20cs4V2bNBm3N60WqZc+VS+OvMNRo J5eirModlQEWF4baagTecoGFfFhYln0EdRHYcRxO7nvGrUF4n8RrSdW0nyz/iC+1WkjZ NzYQ== X-Gm-Message-State: AOAM532kdvyzty+J3EYhYlYxpNuqFF+E1qE11vcFn4G+JEDKnMHiWQGc SYZyjWCxJhmVmXNf3aCFTdJPeuB2zsdW X-Google-Smtp-Source: ABdhPJzTYsWBUGdK72VvINl7XaD0PKLJ71mjf+qeZuZNJdzndAMby8QNmSvqOW5KMKvoINhM7keokK5HEni1 X-Received: from venture.svl.corp.google.com ([2620:15c:2a3:200:9986:338a:477f:1df7]) (user=venture job=sendgmr) by 2002:a05:6902:154d:: with SMTP id r13mr43465529ybu.314.1641506442894; Thu, 06 Jan 2022 14:00:42 -0800 (PST) Date: Thu, 6 Jan 2022 14:00:38 -0800 Message-Id: <20220106220038.3658586-1-venture@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.34.1.448.ga2b2bfdf31-goog Subject: [PATCH] linux-user: rt_sigprocmask, check read perms first From: Patrick Venture To: laurent@vivier.eu Cc: qemu-devel@nongnu.org, Shu-Chun Weng , Patrick Venture X-Host-Lookup-Failed: Reverse DNS lookup failed for 2607:f8b0:4864:20::b4a (failed) Received-SPF: pass client-ip=2607:f8b0:4864:20::b4a; envelope-from=3imbXYQcKCskAt2896tv33v0t.r315t19-stAt0232v29.36v@flex--venture.bounces.google.com; helo=mail-yb1-xb4a.google.com X-Spam_score_int: -87 X-Spam_score: -8.8 X-Spam_bar: -------- X-Spam_report: (-8.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_MED=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RDNS_NONE=0.793, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, USER_IN_DEF_DKIM_WL=-7.5 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Shu-Chun Weng Linux kernel does it this way (checks read permission before validating `how`) and the latest version of ABSL's `AddressIsReadable()` depends on this behavior. c.f. https://github.com/torvalds/linux/blob/9539ba4308ad5bdca6cb41c7b73cbb9f796dcdd7/kernel/signal.c#L3147 Reviewed-by: Patrick Venture Signed-off-by: Shu-Chun Weng --- linux-user/syscall.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/linux-user/syscall.c b/linux-user/syscall.c index ce9d64896c..3070d31f34 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -9491,6 +9491,11 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1, } if (arg2) { + if (!(p = lock_user(VERIFY_READ, arg2, sizeof(target_sigset_t), 1))) + return -TARGET_EFAULT; + target_to_host_sigset(&set, p); + unlock_user(p, arg2, 0); + set_ptr = &set; switch(how) { case TARGET_SIG_BLOCK: how = SIG_BLOCK; @@ -9504,11 +9509,6 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1, default: return -TARGET_EINVAL; } - if (!(p = lock_user(VERIFY_READ, arg2, sizeof(target_sigset_t), 1))) - return -TARGET_EFAULT; - target_to_host_sigset(&set, p); - unlock_user(p, arg2, 0); - set_ptr = &set; } else { how = 0; set_ptr = NULL;