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 C5C1AEB8FB7 for ; Wed, 6 Sep 2023 10:26:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238889AbjIFK0Z (ORCPT ); Wed, 6 Sep 2023 06:26:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53510 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238847AbjIFK0X (ORCPT ); Wed, 6 Sep 2023 06:26:23 -0400 Received: from mail-yw1-x1149.google.com (mail-yw1-x1149.google.com [IPv6:2607:f8b0:4864:20::1149]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E7AAB10C8 for ; Wed, 6 Sep 2023 03:26:19 -0700 (PDT) Received: by mail-yw1-x1149.google.com with SMTP id 00721157ae682-58cb845f2f2so36102387b3.1 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=KxGC2WvjXRBYAzBVLQL7FgnpvA/ATWhmSQeTosHzI/Q0Sx9Y2M1N4vFGFHDVW4ucbY 7EUmQwf18UiGnlHFTXQMs7ZXDE6IFqHpgE8KvjGq1ryQ2Y9uADYKsHzdziCmwz/2dFTU i9PeUjVsjzZZJ+G2E7wi7a060hw5mLl/1iaFSDMNmJ4L93sEFGuU1MpAUxhAW/cFhatN 5FUnqoqCF5rspPAuuRhh/cZsslJ1s3hJ3VNsxjLZXNjfEsxFRAbrKoVvpbI+Od6cwW3r PZT3bOTiHbM9WlduXrgMiPZq8GCENDUsmphMWZ3tJ2HJPAUUU/kF8fMAZsyn4r9ucCuO Pv+g== X-Gm-Message-State: AOJu0YzPRbDWGTds0Qgms07uSwED/1GUak2N02REkXXiyoSAtpCqsedE szsqK1TGYPPYGPIVF5Bk1UWi8wuElA== 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: linux-kernel@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