From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: + fs-filesystemsc-downgrade-user-reachable-warn_once-to-pr_warn_once.patch added to -mm tree Date: Thu, 12 Mar 2020 15:29:43 -0700 Message-ID: <20200312222943.O1sOXgoTP%akpm@linux-foundation.org> References: <20200305222751.6d781a3f2802d79510941e4e@linux-foundation.org> Reply-To: linux-kernel@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.29.99]:52266 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727064AbgCLW3p (ORCPT ); Thu, 12 Mar 2020 18:29:45 -0400 In-Reply-To: <20200305222751.6d781a3f2802d79510941e4e@linux-foundation.org> Sender: mm-commits-owner@vger.kernel.org List-Id: mm-commits@vger.kernel.org To: ast@kernel.org, ebiggers@google.com, gregkh@linuxfoundation.org, jeffv@google.com, jeyu@kernel.org, keescook@chromium.org, mcgrof@kernel.org, mm-commits@vger.kernel.org, neilb@suse.com, stable@vger.kernel.org The patch titled Subject: fs/filesystems.c: downgrade user-reachable WARN_ONCE() to pr_warn_once() has been added to the -mm tree. Its filename is fs-filesystemsc-downgrade-user-reachable-warn_once-to-pr_warn_once.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/fs-filesystemsc-downgrade-user-reachable-warn_once-to-pr_warn_once.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/fs-filesystemsc-downgrade-user-reachable-warn_once-to-pr_warn_once.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Eric Biggers Subject: fs/filesystems.c: downgrade user-reachable WARN_ONCE() to pr_warn_once() After request_module(), nothing is stopping the module from being unloaded until someone takes a reference to it via try_get_module(). The WARN_ONCE() in get_fs_type() is thus user-reachable, via userspace running 'rmmod' concurrently. Since WARN_ONCE() is for kernel bugs only, not for user-reachable situations, downgrade this warning to pr_warn_once(). Link: http://lkml.kernel.org/r/20200312202552.241885-3-ebiggers@kernel.org Signed-off-by: Eric Biggers Cc: Alexei Starovoitov Cc: Greg Kroah-Hartman Cc: Jeff Vander Stoep Cc: Jessica Yu Cc: Kees Cook Cc: Luis Chamberlain Cc: NeilBrown Cc: Signed-off-by: Andrew Morton --- fs/filesystems.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/fs/filesystems.c~fs-filesystemsc-downgrade-user-reachable-warn_once-to-pr_warn_once +++ a/fs/filesystems.c @@ -272,7 +272,9 @@ struct file_system_type *get_fs_type(con fs = __get_fs_type(name, len); if (!fs && (request_module("fs-%.*s", len, name) == 0)) { fs = __get_fs_type(name, len); - WARN_ONCE(!fs, "request_module fs-%.*s succeeded, but still no fs?\n", len, name); + if (!fs) + pr_warn_once("request_module fs-%.*s succeeded, but still no fs?\n", + len, name); } if (dot && fs && !(fs->fs_flags & FS_HAS_SUBTYPE)) { _ Patches currently in -mm which might be from ebiggers@google.com are kmod-make-request_module-return-an-error-when-autoloading-is-disabled.patch fs-filesystemsc-downgrade-user-reachable-warn_once-to-pr_warn_once.patch docs-admin-guide-document-the-kernelmodprobe-sysctl.patch selftests-kmod-test-disabling-module-autoloading.patch