From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 45EACEB8FA5 for ; Wed, 6 Sep 2023 10:26:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230389AbjIFK0Y (ORCPT ); Wed, 6 Sep 2023 06:26:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53500 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238852AbjIFK0X (ORCPT ); Wed, 6 Sep 2023 06:26:23 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E703110C7 for ; Wed, 6 Sep 2023 03:26:19 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id 3f1490d57ef6-d7ec9300c51so2924092276.3 for ; Wed, 06 Sep 2023 03:26:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1693995979; x=1694600779; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=bd8xPMJuwIaL4g5So5Hpw2FKK/Xq7RuyWEq/PvNzxXE=; b=bd3P5L2QfUWkrIhT2st/O48iS8Ew2tRAYPpzoyBE2S2T5Nex+LsZHGVxfdbPO9P8R5 +25y3HAaekcS809uNaqHU2VXed4HB3GA0awjBb//vogVM7eZ+C5h2GFI3MU6bBcZ+x3q fyhsyvYTmdLK/QODO4R/C9onqZqddqdpeEcQ9jh9Q3A4JTAxwCJUYIocWDHz1d5Mxnmg +48aJ5b9JV5yr2xCrWcrTVIC4I3FMdihSEfcASYkYIa9LdcSG0J1cU1kiUsFH67zvGBL w4T1ysNJeR+saPZc5grIGMNYlrlL/tD2Oc20AiPP8JgIWR4Shr+cXgLjekNq6Tus/Z/9 3MyQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1693995979; x=1694600779; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=bd8xPMJuwIaL4g5So5Hpw2FKK/Xq7RuyWEq/PvNzxXE=; b=auE5DfDORT0mkgI5FfYDcvzm6jNMjjZN6rKMQRzos1OASHDEo/iezCcgDFVZRvFilz WyK0Q6zbvBS9YgDrALAyYadl7+AvoCyxh8+vWpn+uyjWCbSrncb4AXusDCSLvLz9S1p+ AVTzMeGKIf0TtyhbXGDjdC+MFOtCqV39y14s/DFEWQWY9aLxqNqKx+K8icsgWUAPlmVe 9V1i3Q0RbddAS7wA93CxKfLhKw+mPfAEyPXNPduw548A9X/9Cx+jHc/fQeFDlQj41P1+ ZcQecluDFWFrqUpyXVxK/BUyC/vgK7twlI0MrSat88t36OvrfsMfHG6esxwbps82c2ju SB6g== X-Gm-Message-State: AOJu0YxYV5ZtVyTeyXAR0BWpaqGV6dq5BXv0y4sOFiMRGQVjC82pbOw8 5zIHxTy2lmbgRsPxVMjR02uX6oiL9Q== X-Google-Smtp-Source: AGHT+IE/UnZx+PImE5pc+JUOpSk02v87E9WHzmFRHcOsG8fNZn7gy5TZNBqX0sBQuSywALVf2UHXb/I+GQ== X-Received: from alpic.c.googlers.com ([fda3:e722:ac3:cc00:28:9cb1:c0a8:1bf2]) (user=alpic job=sendgmr) by 2002:a25:ca87:0:b0:cb6:6c22:d0f8 with SMTP id a129-20020a25ca87000000b00cb66c22d0f8mr383370ybg.4.1693995979209; Wed, 06 Sep 2023 03:26:19 -0700 (PDT) Date: Wed, 6 Sep 2023 12:25:57 +0200 Mime-Version: 1.0 X-Mailer: git-send-email 2.42.0.283.g2d96d420d3-goog Message-ID: <20230906102557.3432236-1-alpic@google.com> Subject: [PATCH] SELinux: Check correct permissions for FS_IOC32_* From: Alfred Piccioni To: Paul Moore , Stephen Smalley , Eric Paris Cc: stable@vger.kernel.org, selinux@vger.kernel.org, linux-kernel@vger.kernel.org, Alfred Piccioni Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Some ioctl commands do not require ioctl permission, but are routed to other permissions such as FILE_GETATTR or FILE_SETATTR. This routing is done by comparing the ioctl cmd to a set of 64-bit flags (FS_IOC_*). However, if a 32-bit process is running on a 64-bit kernel, it emmits 32-bit flags (FS_IOC32_*) for certain ioctl operations. These flags are being checked erroneoulsy, which leads to these ioctl operations being routed to the ioctl permission, rather than the correct file permissions. Two possible solutions exist: - Trim parameter "cmd" to a u16 so that only the last two bytes are checked in the case statement. - Explicitily add the FS_IOC32_* codes to the case statement. Solution 2 was chosen because it is a minimal explicit change. Solution 1 is a more elegant change, but is less explicit, as the switch statement appears to only check the FS_IOC_* codes upon first reading. Fixes: 0b24dcb7f2f7 ("Revert "selinux: simplify ioctl checking"") Signed-off-by: Alfred Piccioni --- security/selinux/hooks.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index d06e350fedee..bba83f437a1d 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -3644,11 +3644,15 @@ static int selinux_file_ioctl(struct file *file, unsigned int cmd, case FIGETBSZ: case FS_IOC_GETFLAGS: case FS_IOC_GETVERSION: + case FS_IOC32_GETFLAGS: + case FS_IOC32_GETVERSION: error = file_has_perm(cred, file, FILE__GETATTR); break; case FS_IOC_SETFLAGS: case FS_IOC_SETVERSION: + case FS_IOC32_SETFLAGS: + case FS_IOC32_SETVERSION: error = file_has_perm(cred, file, FILE__SETATTR); break; base-commit: 50a510a78287c15cee644f345ef8bac8977986a7 -- 2.42.0.283.g2d96d420d3-goog