From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-3704313-1519414842-2-399967384613194161 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.001, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES encaro, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1519414842; b=Fzti4XN/DhLU1cDuAKK2aWDX1LHHZP2Qlt0liuO8g0cRASI aU/0dJYoYglXEKLQxguQG4RJ/Cjqxva8/ZKMRQEyc+t950nVaOHPf25Qp1Eksj+z KEFhQgJIBS+Z3OkXzvlb4mcp/z3D5a+JhQCnwdlv4LxwXYxy/+wgfKa6XU7euWDG 0FAcbaPGdX746Xe+9W84+VhcqCvISE2ne+thFJkSgdhl8BX2i5MH0KqAumX2DNws vQ6BmqI1VLWszSjAKWGj2iLDjmQpg9YevbrIOeDNAiyLK6oyzxiFZabhXDzP94bJ D1Aw22dpLwt8Dw+QlHXHbUNheFtuSUAlJ6766mQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-type:sender :list-id; s=arctest; t=1519414842; bh=iLtjd20SHaFlAZ3LR+oKKplS/m lOvvwjtZqi62p2R7E=; b=kswX9239QECVMaPnlDhMEXgHk1S0u2lyQmImdPtUTG 8LU1Hkd60KFpcIX39PamsgFWUrx9X9jt9fCGGfHI4Lmk90kjXGycJ2qa0alt8ZaM Fit52ZFTr1vFXLtfSxuDN8juROYfrjZkyEjVZvDlpJU19CnnK9wLzHtGV5AgZgJI KWagNrWZyNwIqD3b8sbC0ZuSmkMwzzy6oPpgl77pA93Kbw1u7xDovmGOFtsdw4iI ELUy57MTfDAxsvIntX80VbezZvrWG7Ki3xOUM6ab77kG8X+goOgoOYwtYT2ZGgx/ zN4AiskoAPlVOsvrpBJOp2VaEgtmpLJ1OlBmn4F11MOA== ARC-Authentication-Results: i=1; mx5.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Authentication-Results: mx5.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934265AbeBWStY (ORCPT ); Fri, 23 Feb 2018 13:49:24 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:45262 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934016AbeBWStX (ORCPT ); Fri, 23 Feb 2018 13:49:23 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+ca425f44816d749e8eb49755567a75ee48cf4a30@syzkaller.appspotmail.com, Sabrina Dubroca , Steffen Klassert Subject: [PATCH 4.14 010/159] xfrm: fix rcu usage in xfrm_get_type_offload Date: Fri, 23 Feb 2018 19:25:18 +0100 Message-Id: <20180223170744.432128760@linuxfoundation.org> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180223170743.086611315@linuxfoundation.org> References: <20180223170743.086611315@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sabrina Dubroca commit 2f10a61cee8fdb9f8da90f5db687e1862b22cf06 upstream. request_module can sleep, thus we cannot hold rcu_read_lock() while calling it. The function also jumps back and takes rcu_read_lock() again (in xfrm_state_get_afinfo()), resulting in an imbalance. This codepath is triggered whenever a new offloaded state is created. Fixes: ffdb5211da1c ("xfrm: Auto-load xfrm offload modules") Reported-by: syzbot+ca425f44816d749e8eb49755567a75ee48cf4a30@syzkaller.appspotmail.com Signed-off-by: Sabrina Dubroca Signed-off-by: Steffen Klassert Signed-off-by: Greg Kroah-Hartman --- net/xfrm/xfrm_state.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/xfrm/xfrm_state.c +++ b/net/xfrm/xfrm_state.c @@ -313,13 +313,14 @@ retry: if ((type && !try_module_get(type->owner))) type = NULL; + rcu_read_unlock(); + if (!type && try_load) { request_module("xfrm-offload-%d-%d", family, proto); try_load = 0; goto retry; } - rcu_read_unlock(); return type; }