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 5F6F8C4360C for ; Sun, 6 Oct 2019 17:27:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 356132133F for ; Sun, 6 Oct 2019 17:27:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570382866; bh=Fn6xdpVicpmIoavvVgPu3S525wzdDrcZykep2c8pD+E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=TM8LjgbCWnwebXIbWp1l691tEewlsBgk/i0YjOGRkQux41k3tvIrPXq2QX+ReMaYc FPJ4UTRnnu/UWzTPU39sEyX9zlkNs5WC5WlJGbX/wYUFE92WGEsNzDs25id1cPdg1+ gki/VGNlnp4ANajCV0dGi9xYZpjbXOmklkD7h0dw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728575AbfJFR1p (ORCPT ); Sun, 6 Oct 2019 13:27:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:53172 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727541AbfJFR1n (ORCPT ); Sun, 6 Oct 2019 13:27:43 -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 F28D62133F; Sun, 6 Oct 2019 17:27:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570382862; bh=Fn6xdpVicpmIoavvVgPu3S525wzdDrcZykep2c8pD+E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=l77dlHJHGkWQZbP71bT+MmOPjWM4bWjI8Bk4+gTuWpAWTE2Z7XjhlVVsB3k0ThsTK tCwjgGnKHQt6NI4mLtEkO2lACja8A6LvdtVCnQRGi6XCNs8sbaJ7e3pXZ+4um2z7DF JL0EDW/tQgBvoV5dvp2kYy+W1ZHPl7LXUWFrIGQo= 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 4.14 66/68] smack: use GFP_NOFS while holding inode_smack::smk_lock Date: Sun, 6 Oct 2019 19:21:42 +0200 Message-Id: <20191006171138.981578804@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191006171108.150129403@linuxfoundation.org> References: <20191006171108.150129403@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 @@ -469,7 +469,7 @@ 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); @@ -504,7 +504,7 @@ 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; @@ -540,7 +540,7 @@ 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 @@ -269,7 +269,7 @@ 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);