From patchwork Mon May 18 05:54:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 11554759 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 65C8290 for ; Mon, 18 May 2020 05:55:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4DD822067D for ; Mon, 18 May 2020 05:55:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="Kdpre7Ex" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726847AbgERFzH (ORCPT ); Mon, 18 May 2020 01:55:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33656 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726786AbgERFzG (ORCPT ); Mon, 18 May 2020 01:55:06 -0400 Received: from mail-pg1-x543.google.com (mail-pg1-x543.google.com [IPv6:2607:f8b0:4864:20::543]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 94CD3C05BD09 for ; Sun, 17 May 2020 22:55:06 -0700 (PDT) Received: by mail-pg1-x543.google.com with SMTP id f4so4308163pgi.10 for ; Sun, 17 May 2020 22:55:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=rPKPZdLWYhVxpx5jrV/H8h0jtqWmPX7wH6A62qnOkus=; b=Kdpre7Exr/pMZGU8QiObZ4ZYPthvQzzf5UzH9ShzOMaqB7qV271cLqRWRlDhna2jMb DVm/UT04r0HB83+/3jJJjOf0vEXktU3iLJWXT+ixvegZsUIA5oFmKv2L6Qos/AG5/Kr4 NUb7howiZnwR14Y8/i+ox9g0yzgIzizw7d/L0= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=rPKPZdLWYhVxpx5jrV/H8h0jtqWmPX7wH6A62qnOkus=; b=WeTq4dEYY+sRmKl2yL24kUvS4nS+frI2wvQpNwyu9lZgutgoqDGCVTpU76LsAafufL YQYf/G09f052+8VCewx5G/RDslBGbDmw3WgdVbXTc4vmLcd0xugDHZ6B4WSgqdMvs7SA rHpXrte+FH6uX/Ze4AzKz2r08c16YZNwX+/c/IfGRYiYGwEDNsJW6lLMYKEImRHnXPF6 VOh7OLGBK+BjwLWbGfDFv4+auUbHK/qSwck74Y4HU6tkNEoKUZ2wts+rTP2E7MdtGm9l /cIQyej/3Q7Qx0tL3ZyGaMj04Wi9sNAlEyzuiM6FNqI+AuVTDc37FJ2k1rpT/K12F4uN uddA== X-Gm-Message-State: AOAM532CAQfG2FMzD1Ku+Q9eTr6utyIX9u0z7ubaP0QWQ8lEazZpFWSZ tKNuSru6JyXpOcEC+f+mBk4m5Q== X-Google-Smtp-Source: ABdhPJxhtS996OCWMkgpeKohWlQufYcB+/tWiUrVycuLTEmz6Rc2lRetBKELSdXVfqF4RuGByiW3Pw== X-Received: by 2002:a63:2bd3:: with SMTP id r202mr13454738pgr.130.1589781306161; Sun, 17 May 2020 22:55:06 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id k5sm7490235pjl.32.2020.05.17.22.55.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 17 May 2020 22:55:03 -0700 (PDT) From: Kees Cook To: Al Viro Cc: Kees Cook , Andrew Morton , Tetsuo Handa , Eric Biggers , Dmitry Vyukov , linux-fsdevel@vger.kernel.org, linux-security-module@vger.kernel.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 1/4] exec: Change uselib(2) IS_SREG() failure to EACCES Date: Sun, 17 May 2020 22:54:54 -0700 Message-Id: <20200518055457.12302-2-keescook@chromium.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200518055457.12302-1-keescook@chromium.org> References: <20200518055457.12302-1-keescook@chromium.org> MIME-Version: 1.0 Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: Change uselib(2)' S_ISREG() error return to EACCES instead of EINVAL so the behavior matches execve(2), and the seemingly documented value. The "not a regular file" failure mode of execve(2) is explicitly documented[1], but it is not mentioned in uselib(2)[2] which does, however, say that open(2) and mmap(2) errors may apply. The documentation for open(2) does not include a "not a regular file" error[3], but mmap(2) does[4], and it is EACCES. [1] http://man7.org/linux/man-pages/man2/execve.2.html#ERRORS [2] http://man7.org/linux/man-pages/man2/uselib.2.html#ERRORS [3] http://man7.org/linux/man-pages/man2/open.2.html#ERRORS [4] http://man7.org/linux/man-pages/man2/mmap.2.html#ERRORS Signed-off-by: Kees Cook Acked-by: Christian Brauner --- fs/exec.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index 06b4c550af5d..30735ce1dc0e 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -139,11 +139,10 @@ SYSCALL_DEFINE1(uselib, const char __user *, library) if (IS_ERR(file)) goto out; - error = -EINVAL; + error = -EACCES; if (!S_ISREG(file_inode(file)->i_mode)) goto exit; - error = -EACCES; if (path_noexec(&file->f_path)) goto exit; From patchwork Mon May 18 05:54:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 11554753 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 C2B2F90 for ; Mon, 18 May 2020 05:55:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A47C1206D4 for ; Mon, 18 May 2020 05:55:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="PmmADXwv" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726919AbgERFzR (ORCPT ); Mon, 18 May 2020 01:55:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33672 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726876AbgERFzH (ORCPT ); Mon, 18 May 2020 01:55:07 -0400 Received: from mail-pg1-x541.google.com (mail-pg1-x541.google.com [IPv6:2607:f8b0:4864:20::541]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5F1A6C05BD0E for ; Sun, 17 May 2020 22:55:07 -0700 (PDT) Received: by mail-pg1-x541.google.com with SMTP id j21so4310492pgb.7 for ; Sun, 17 May 2020 22:55:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=5Q1i6oRikNLeZklgvYSkpM1EVlw/CTM/4XamXlqlvKw=; b=PmmADXwv4NMqpXwbOWvucRxbEW9uHuZYDIxA2TsDvioy03mFxkJduyC+qs3bYF9f9P RvWd0e5uTz+r6q0dgzc030QSXDeIb2IuAljXkzaNUw6EKUgZTTBgPxbOHwMbML23cg7F sB4mfaMCVqy2DoEsEuRAteyVH/1UNqIKq13s8= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=5Q1i6oRikNLeZklgvYSkpM1EVlw/CTM/4XamXlqlvKw=; b=g4jjJiREW+2dzm/Ip8zms8tPj9XpPabj21r7S9F11tchK5oirc33NyweA50hsB9Vfv EgLCrjen27fUaBU+exT58dEvbBz7kwHAzBjjOSWRmv7a0CFPiUVTaY+3gxQQ+NRTJSDX EM8Xc9dAL5pUrM+zJF5rObIUMd00QP/HoWM82/hRYAh/VuWOpBaW2hcb5yqj2Rbl+arb yeCQVAZUnxb/ZxTiWFzT5W8wHGWtfC7/F0akPGoxHcDqA+OU/JXedzqLkpMgsR3l3k1W Y42dhphYcLybWivG+LcMCD6BO4Ta+eCYr8+9QKn5C1UiQzK5qWV2FOxty+Zd0FPKOqdP stYw== X-Gm-Message-State: AOAM532nSwexjKvR+Q1gyIznN9nP4DdHiaE0kUFJwHSSgO1Mh1Wh2Caq ONqIPlCWZPNdcaLNddZemAcaAQ== X-Google-Smtp-Source: ABdhPJwH6ud9V9wj2fVaRFrgEB2v7VP/Tc4l2Vb30aDG6ICq9TytrkA9z9Q8L1Shdn9DcbSlyL70DQ== X-Received: by 2002:a63:3c53:: with SMTP id i19mr13366855pgn.147.1589781306926; Sun, 17 May 2020 22:55:06 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id t25sm4143998pgo.7.2020.05.17.22.55.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 17 May 2020 22:55:03 -0700 (PDT) From: Kees Cook To: Al Viro Cc: Kees Cook , Andrew Morton , Tetsuo Handa , Eric Biggers , Dmitry Vyukov , linux-fsdevel@vger.kernel.org, linux-security-module@vger.kernel.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 2/4] exec: Relocate S_ISREG() check Date: Sun, 17 May 2020 22:54:55 -0700 Message-Id: <20200518055457.12302-3-keescook@chromium.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200518055457.12302-1-keescook@chromium.org> References: <20200518055457.12302-1-keescook@chromium.org> MIME-Version: 1.0 Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: The execve(2)/uselib(2) syscalls have always rejected non-regular files. Recently, it was noticed that a deadlock was introduced when trying to execute pipes, as the S_ISREG() test was happening too late. This was fixed in commit 73601ea5b7b1 ("fs/open.c: allow opening only regular files during execve()"), but it was added after inode_permission() had already run, which meant LSMs could see bogus attempts to execute non-regular files. Move the test earlier. Also include a comment with the redundant S_ISREG() checks at the end of execve(2)/uselib(2) to note that they are present to avoid any mistakes. Finally, instead of dereferencing the inode, use dcache for S_ISREG() test. My notes on the call path, and related arguments, checks, etc: do_open_execat() struct open_flags open_exec_flags = { .open_flag = O_LARGEFILE | O_RDONLY | __FMODE_EXEC, ... do_filp_open(dfd, filename, open_flags) path_openat(nameidata, open_flags, flags) /* f_mode populated from open_flags in alloc_empty_file() */ file = alloc_empty_file(open_flags, current_cred()); do_open(nameidata, file, open_flags) /* new location of FMODE_EXEC vs S_ISREG() test */ may_open(path, acc_mode, open_flag) inode_permission(inode, MAY_OPEN | acc_mode) security_inode_permission(inode, acc_mode) vfs_open(path, file) do_dentry_open(file, path->dentry->d_inode, open) /* old location of FMODE_EXEC vs S_ISREG() test */ security_file_open(f) open() Signed-off-by: Kees Cook --- fs/exec.c | 8 ++++++++ fs/namei.c | 4 ++++ fs/open.c | 6 ------ 3 files changed, 12 insertions(+), 6 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index 30735ce1dc0e..f0c80a8b9ccd 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -139,6 +139,10 @@ SYSCALL_DEFINE1(uselib, const char __user *, library) if (IS_ERR(file)) goto out; + /* + * do_open() has already checked for this, but we can be extra + * cautious and check again at the very end too. + */ error = -EACCES; if (!S_ISREG(file_inode(file)->i_mode)) goto exit; @@ -860,6 +864,10 @@ static struct file *do_open_execat(int fd, struct filename *name, int flags) if (IS_ERR(file)) goto out; + /* + * do_open() has already checked for this, but we can be extra + * cautious and check again at the very end too. + */ err = -EACCES; if (!S_ISREG(file_inode(file)->i_mode)) goto exit; diff --git a/fs/namei.c b/fs/namei.c index a320371899cf..b9408aacaaa4 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -3212,6 +3212,10 @@ static int do_open(struct nameidata *nd, if ((nd->flags & LOOKUP_DIRECTORY) && !d_can_lookup(nd->path.dentry)) return -ENOTDIR; + /* Any file opened for execution has to be a regular file. */ + if ((file->f_flags & FMODE_EXEC) && !d_is_reg(nd->path.dentry)) + return -EACCES; + do_truncate = false; acc_mode = op->acc_mode; if (file->f_mode & FMODE_CREATED) { diff --git a/fs/open.c b/fs/open.c index 719b320ede52..bb16e4e3cd57 100644 --- a/fs/open.c +++ b/fs/open.c @@ -753,12 +753,6 @@ static int do_dentry_open(struct file *f, return 0; } - /* Any file opened for execve()/uselib() has to be a regular file. */ - if (unlikely(f->f_flags & FMODE_EXEC && !S_ISREG(inode->i_mode))) { - error = -EACCES; - goto cleanup_file; - } - if (f->f_mode & FMODE_WRITE && !special_file(inode->i_mode)) { error = get_write_access(inode); if (unlikely(error)) From patchwork Mon May 18 05:54:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 11554767 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 D942290 for ; Mon, 18 May 2020 05:55:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C130C206D4 for ; Mon, 18 May 2020 05:55:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="iPdCIuod" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726658AbgERFzF (ORCPT ); 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[198.145.64.163]) by smtp.gmail.com with ESMTPSA id m18sm7591576pjl.14.2020.05.17.22.55.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 17 May 2020 22:55:03 -0700 (PDT) From: Kees Cook To: Al Viro Cc: Kees Cook , Andrew Morton , Tetsuo Handa , Eric Biggers , Dmitry Vyukov , linux-fsdevel@vger.kernel.org, linux-security-module@vger.kernel.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 3/4] exec: Relocate path_noexec() check Date: Sun, 17 May 2020 22:54:56 -0700 Message-Id: <20200518055457.12302-4-keescook@chromium.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200518055457.12302-1-keescook@chromium.org> References: <20200518055457.12302-1-keescook@chromium.org> MIME-Version: 1.0 Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: The path_noexec() check, like the regular file check, was happening too late, letting LSMs see impossible execve()s. Check it earlier as well and collect the redundant fs/exec.c path_noexec() test under the same robustness comment as the S_ISREG() check. My notes on the call path, and related arguments, checks, etc: do_open_execat() struct open_flags open_exec_flags = { .open_flag = O_LARGEFILE | O_RDONLY | __FMODE_EXEC, ... do_filp_open(dfd, filename, open_flags) path_openat(nameidata, open_flags, flags) /* f_mode populated from open_flags in alloc_empty_file() */ file = alloc_empty_file(open_flags, current_cred()); do_open(nameidata, file, open_flags) /* new location of FMODE_EXEC vs path_noexec() test */ may_open(path, acc_mode, open_flag) inode_permission(inode, MAY_OPEN | acc_mode) security_inode_permission(inode, acc_mode) vfs_open(path, file) do_dentry_open(file, path->dentry->d_inode, open) security_file_open(f) open() /* old location of path_noexec() test */ Signed-off-by: Kees Cook --- fs/exec.c | 6 ++---- fs/namei.c | 5 +++-- 2 files changed, 5 insertions(+), 6 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index f0c80a8b9ccd..a34093323aa1 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -140,13 +140,12 @@ SYSCALL_DEFINE1(uselib, const char __user *, library) goto out; /* - * do_open() has already checked for this, but we can be extra + * do_open() has already checked for these, but we can be extra * cautious and check again at the very end too. */ error = -EACCES; if (!S_ISREG(file_inode(file)->i_mode)) goto exit; - if (path_noexec(&file->f_path)) goto exit; @@ -865,13 +864,12 @@ static struct file *do_open_execat(int fd, struct filename *name, int flags) goto out; /* - * do_open() has already checked for this, but we can be extra + * do_open() has already checked for these, but we can be extra * cautious and check again at the very end too. */ err = -EACCES; if (!S_ISREG(file_inode(file)->i_mode)) goto exit; - if (path_noexec(&file->f_path)) goto exit; diff --git a/fs/namei.c b/fs/namei.c index b9408aacaaa4..6bb1b6624bad 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -3212,8 +3212,9 @@ static int do_open(struct nameidata *nd, if ((nd->flags & LOOKUP_DIRECTORY) && !d_can_lookup(nd->path.dentry)) return -ENOTDIR; - /* Any file opened for execution has to be a regular file. */ - if ((file->f_flags & FMODE_EXEC) && !d_is_reg(nd->path.dentry)) + /* Opening for execution requires a regular file on an exec mnt. */ + if ((file->f_flags & FMODE_EXEC) && (!d_is_reg(nd->path.dentry) || + path_noexec(&nd->path))) return -EACCES; do_truncate = false; From patchwork Mon May 18 05:54:57 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 11554765 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 53BAF13B1 for ; Mon, 18 May 2020 05:55:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3CAEB20709 for ; Mon, 18 May 2020 05:55:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="lSJ7AfkV" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726705AbgERFzG (ORCPT ); Mon, 18 May 2020 01:55:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33660 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726573AbgERFzF (ORCPT ); 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[198.145.64.163]) by smtp.gmail.com with ESMTPSA id x66sm7653474pfb.173.2020.05.17.22.55.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 17 May 2020 22:55:03 -0700 (PDT) From: Kees Cook To: Al Viro Cc: Kees Cook , Andrew Morton , Tetsuo Handa , Eric Biggers , Dmitry Vyukov , linux-fsdevel@vger.kernel.org, linux-security-module@vger.kernel.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 4/4] fs: Include FMODE_EXEC when converting flags to f_mode Date: Sun, 17 May 2020 22:54:57 -0700 Message-Id: <20200518055457.12302-5-keescook@chromium.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200518055457.12302-1-keescook@chromium.org> References: <20200518055457.12302-1-keescook@chromium.org> MIME-Version: 1.0 Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: Include FMODE_EXEC when building the f_mode field, so that code can actually test the correct field and values. Only three places actually examine f_flags for FMODE_EXEC: fs/open.c: if (unlikely((f->f_mode & FMODE_EXEC) && !S_ISREG(inode->i_mode))) { include/linux/fsnotify.h: if (file->f_mode & FMODE_EXEC) { include/linux/fsnotify.h: if (file->f_mode & FMODE_EXEC) Signed-off-by: Kees Cook --- I assume there must be some reason for FMODE_EXEC not being pulled into f_mode, but I couldn't find it. I guess this is my attempt to either fix an oversight or to learn by flames. :) --- fs/namei.c | 4 ++-- include/linux/fs.h | 3 ++- include/linux/fsnotify.h | 4 ++-- 3 files changed, 6 insertions(+), 5 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index 6bb1b6624bad..362b1cc75f5c 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -3213,8 +3213,8 @@ static int do_open(struct nameidata *nd, return -ENOTDIR; /* Opening for execution requires a regular file on an exec mnt. */ - if ((file->f_flags & FMODE_EXEC) && (!d_is_reg(nd->path.dentry) || - path_noexec(&nd->path))) + if ((file->f_mode & FMODE_EXEC) && (!d_is_reg(nd->path.dentry) || + path_noexec(&nd->path))) return -EACCES; do_truncate = false; diff --git a/include/linux/fs.h b/include/linux/fs.h index 4f6f59b4f22a..8a2cabdcf531 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3545,10 +3545,11 @@ int __init get_filesystem_list(char *buf); #define __FMODE_EXEC ((__force int) FMODE_EXEC) #define __FMODE_NONOTIFY ((__force int) FMODE_NONOTIFY) +#define __SMUGGLED_FMODE_FLAGS (__FMODE_EXEC | __FMODE_NONOTIFY) #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE]) #define OPEN_FMODE(flag) ((__force fmode_t)(((flag + 1) & O_ACCMODE) | \ - (flag & __FMODE_NONOTIFY))) + (flag & __SMUGGLED_FMODE_FLAGS))) static inline bool is_sxid(umode_t mode) { diff --git a/include/linux/fsnotify.h b/include/linux/fsnotify.h index 5ab28f6c7d26..86761ed4b434 100644 --- a/include/linux/fsnotify.h +++ b/include/linux/fsnotify.h @@ -90,7 +90,7 @@ static inline int fsnotify_perm(struct file *file, int mask) if (mask & MAY_OPEN) { fsnotify_mask = FS_OPEN_PERM; - if (file->f_flags & __FMODE_EXEC) { + if (file->f_mode & FMODE_EXEC) { ret = fsnotify_file(file, FS_OPEN_EXEC_PERM); if (ret) @@ -264,7 +264,7 @@ static inline void fsnotify_open(struct file *file) { __u32 mask = FS_OPEN; - if (file->f_flags & __FMODE_EXEC) + if (file->f_mode & FMODE_EXEC) mask |= FS_OPEN_EXEC; fsnotify_file(file, mask);