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 X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B5955C10F14 for ; Sun, 6 Oct 2019 17:38:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8B3EE2087E for ; Sun, 6 Oct 2019 17:38:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570383536; bh=axRY1t3IiJXvhDfhisGregAKW7gK5qc9mX5zwfxCozw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=z1+NzVirIMkYvkaA4uIxq1O/jT+58ouoM6ycMsyvSltlChb7OdQyiZ2ermzPHDWn8 R+YHbAUTDwjZkftubJ7QQJy1RIwoqxTOPpLr0jU193obz6xWxKybJE/GJHcBmzzV1l c3tm0ClbTQXxgf4Z/EtmtoJwLj8ongHlHOVaoy1s= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730704AbfJFRiz (ORCPT ); Sun, 6 Oct 2019 13:38:55 -0400 Received: from mail.kernel.org ([198.145.29.99]:38244 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730664AbfJFRiu (ORCPT ); Sun, 6 Oct 2019 13:38:50 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2C0542053B; Sun, 6 Oct 2019 17:38:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570383529; bh=axRY1t3IiJXvhDfhisGregAKW7gK5qc9mX5zwfxCozw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=koMUuhrcKwwOWO53tUYUKVKDM5I37/WO4Naoccrv5h5D+1sQUt3hZPyfOl8wQO1VS /KL3o4+Fo7Zm74D5SBdUXmVJOpXedXhErgdJO14IppC+qyANhQLmr3qasgsChwN7zo 5fNK9YEm93OOSDJ9h6hoBjhVcD5j4yFciDUVrYpg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+0eefc1e06a77d327a056@syzkaller.appspotmail.com, Eric Biggers , Casey Schaufler Subject: [PATCH 5.2 131/137] smack: use GFP_NOFS while holding inode_smack::smk_lock Date: Sun, 6 Oct 2019 19:21:55 +0200 Message-Id: <20191006171220.281965824@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191006171209.403038733@linuxfoundation.org> References: <20191006171209.403038733@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric Biggers commit e5bfad3d7acc5702f32aafeb388362994f4d7bd0 upstream. inode_smack::smk_lock is taken during smack_d_instantiate(), which is called during a filesystem transaction when creating a file on ext4. Therefore to avoid a deadlock, all code that takes this lock must use GFP_NOFS, to prevent memory reclaim from waiting for the filesystem transaction to complete. Reported-by: syzbot+0eefc1e06a77d327a056@syzkaller.appspotmail.com Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers Signed-off-by: Casey Schaufler Signed-off-by: Greg Kroah-Hartman --- security/smack/smack_access.c | 6 +++--- security/smack/smack_lsm.c | 2 +- 2 files changed, 4 insertions(+), 4 deletions(-) --- a/security/smack/smack_access.c +++ b/security/smack/smack_access.c @@ -465,7 +465,7 @@ char *smk_parse_smack(const char *string if (i == 0 || i >= SMK_LONGLABEL) return ERR_PTR(-EINVAL); - smack = kzalloc(i + 1, GFP_KERNEL); + smack = kzalloc(i + 1, GFP_NOFS); if (smack == NULL) return ERR_PTR(-ENOMEM); @@ -500,7 +500,7 @@ int smk_netlbl_mls(int level, char *cats if ((m & *cp) == 0) continue; rc = netlbl_catmap_setbit(&sap->attr.mls.cat, - cat, GFP_KERNEL); + cat, GFP_NOFS); if (rc < 0) { netlbl_catmap_free(sap->attr.mls.cat); return rc; @@ -536,7 +536,7 @@ struct smack_known *smk_import_entry(con if (skp != NULL) goto freeout; - skp = kzalloc(sizeof(*skp), GFP_KERNEL); + skp = kzalloc(sizeof(*skp), GFP_NOFS); if (skp == NULL) { skp = ERR_PTR(-ENOMEM); goto freeout; --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -288,7 +288,7 @@ static struct smack_known *smk_fetch(con if (!(ip->i_opflags & IOP_XATTR)) return ERR_PTR(-EOPNOTSUPP); - buffer = kzalloc(SMK_LONGLABEL, GFP_KERNEL); + buffer = kzalloc(SMK_LONGLABEL, GFP_NOFS); if (buffer == NULL) return ERR_PTR(-ENOMEM);