From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-3704313-1519414327-2-2220707558894778378 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 en, 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=1519414326; b=VEiECHNuuNH1xy7BrwxHXnv0X0aMaS0HttXcCD3dAHnoZ1U oWX3wspsD0qsSzksWwmAFomlCg3wkN+MQBX8G5q1KMjaWUvYdzEBmUR8rwzHRvWm J6hgIfEppUaJGdUN5u7CdINvPMrm5w1fO3MczeJrABaXQlLcrlsQ0eHR9LQZ8vlO /fHXHW8B+1cc/8v1Lq/yL5nLz3LjxZHWGudaCM+qIWp9ww9NXLR8BTZ/oQUWnBGm Pz3pEmRK3LeULmjbutBMAmqwuI+L9FSMPt8nVeGVN89S18tR0bQp1Tzh4BbqLda+ D0OPS1ZGD94aEXVZrvwEf5M3bxgxsy33UJ4gWAA== 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=1519414326; bh=lyypm2p/KVnq5JoQpfNBWNghNG z2CTDPrlj0xlXY8uo=; b=LxKs4E/2pltofqNaggdGQc0R4oDgjxXfwzbDgPEOaJ cxygRhnnIQxmLkqgQhm3aaai/1ir4d4ct/vO8nxt+ANKHmU5TnpsDb05L0E+eV/d nShUwspiaulbDpqTKlJDdovyr6FrNsbdysPYhiXQ0iBIkDVoLI3/y7af/yga7CN1 CbdJOT32V+Iq05eIyJLFR9Z5UfDPFrRmZEG9u0wIy19+bO25hQ0US9RTGhmrLuKk 1YPZMh1cDCk64ZhcBwBiSzBPv8S+yCTWhn5Vuik0KzwYtoTYLXLUd5OfoXvKqv8g neUA2X2mJQmaMbg1UBeLa05/A4LFPAN+5kZKzrltFbEQ== ARC-Authentication-Results: i=1; mx4.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: mx4.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 S1754743AbeBWTbu (ORCPT ); Fri, 23 Feb 2018 14:31:50 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:46024 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934954AbeBWSv0 (ORCPT ); Fri, 23 Feb 2018 13:51:26 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+a2a3c4909716e271487e@syzkaller.appspotmail.com, Martijn Coenen Subject: [PATCH 4.14 051/159] ANDROID: binder: synchronize_rcu() when using POLLFREE. Date: Fri, 23 Feb 2018 19:25:59 +0100 Message-Id: <20180223170749.735086588@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: Martijn Coenen commit 5eeb2ca02a2f6084fc57ae5c244a38baab07033a upstream. To prevent races with ep_remove_waitqueue() removing the waitqueue at the same time. Reported-by: syzbot+a2a3c4909716e271487e@syzkaller.appspotmail.com Signed-off-by: Martijn Coenen Cc: stable # 4.14+ Signed-off-by: Greg Kroah-Hartman --- drivers/android/binder.c | 9 +++++++++ 1 file changed, 9 insertions(+) --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -4322,6 +4322,15 @@ static int binder_thread_release(struct binder_inner_proc_unlock(thread->proc); + /* + * This is needed to avoid races between wake_up_poll() above and + * and ep_remove_waitqueue() called for other reasons (eg the epoll file + * descriptor being closed); ep_remove_waitqueue() holds an RCU read + * lock, so we can be sure it's done after calling synchronize_rcu(). + */ + if (thread->looper & BINDER_LOOPER_STATE_POLL) + synchronize_rcu(); + if (send_reply) binder_send_failed_reply(send_reply, BR_DEAD_REPLY); binder_release_work(proc, &thread->todo);