From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from conuserg-11.nifty.com (conuserg-11.nifty.com [210.131.2.78]) by sourceware.org (Postfix) with ESMTPS id E8EF23857C50 for ; Fri, 19 Nov 2021 18:39:28 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org E8EF23857C50 Authentication-Results: sourceware.org; dmarc=fail (p=none dis=none) header.from=nifty.ne.jp Authentication-Results: sourceware.org; spf=fail smtp.mailfrom=nifty.ne.jp Received: from localhost.localdomain (z221123.dynamic.ppp.asahi-net.or.jp [110.4.221.123]) (authenticated) by conuserg-11.nifty.com with ESMTP id 1AJId9cp019511; Sat, 20 Nov 2021 03:39:14 +0900 DKIM-Filter: OpenDKIM Filter v2.10.3 conuserg-11.nifty.com 1AJId9cp019511 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nifty.ne.jp; s=dec2015msa; t=1637347154; bh=57erYlq/U1dHBJmYotJns+Ypprv8mEmRUHgzaFgns38=; h=From:To:Cc:Subject:Date:From; b=iyl5RDECUyrIedv9SSfZC10AwlNzqlw5aE8ucPK/udePzpVQZFjOZt6D9GVnyZ7+6 uUfhTYpK3WRTfIjtULrwliSORKLohWCKsZ4SZXAt3trp1ElZYQ1T4etM3sw5XnYRgd 2Q3oDNh6wGBAcD0fVhj/URNwuEnqr2PHd8dv3YVI685RY7PMc8o6aqWkrenbqr86i9 kOOxMY2M++wTexgVsZkW6+uAJcmHtpL8mrEhqXRyh5KpaD3zOEgBpczCt+l/DWlMjy f5Q9awIq10G/tff1jyejvfb112TjzCBpg15frK7aFqDjk/nluQiP8NUiE5dn1tLkCS 513NpmFJTZAmQ== X-Nifty-SrcIP: [110.4.221.123] From: Takashi Yano To: cygwin-patches@cygwin.com Subject: [PATCH] Cygwin: sigproc: Fix potential race issue regarding exit_state. Date: Sat, 20 Nov 2021 03:39:05 +0900 Message-Id: <20211119183905.1878-1-takashi.yano@nifty.ne.jp> X-Mailer: git-send-email 2.33.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-10.4 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: cygwin-patches@cygwin.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Cygwin core component patch submission and discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 19 Nov 2021 18:39:33 -0000 - If sig_send() is called while another thread is processing exit(), race issue regarding exit_state may occur. This patch fixes the issue. --- winsup/cygwin/sigproc.cc | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/winsup/cygwin/sigproc.cc b/winsup/cygwin/sigproc.cc index fde41a9f6..02d875a7f 100644 --- a/winsup/cygwin/sigproc.cc +++ b/winsup/cygwin/sigproc.cc @@ -603,11 +603,6 @@ sig_send (_pinfo *p, siginfo_t& si, _cygtls *tls) its_me = false; } - /* Do not send signal to myself if exiting, which will be - ignored in wait_sig thread. */ - if (its_me && exit_state > ES_EXIT_STARTING && si.si_signo > 0) - goto out; - if (its_me) sendsig = my_sendsig; else @@ -1372,7 +1367,7 @@ wait_sig (VOID *) sigq.retry = false; /* Don't process signals when we start exiting */ if (exit_state > ES_EXIT_STARTING && pack.si.si_signo > 0) - continue; + goto skip_process_signal; sigset_t dummy_mask; threadlist_t *tl_entry; @@ -1384,8 +1379,10 @@ wait_sig (VOID *) pack.mask = &dummy_mask; } - sigpacket *q = &sigq.start; - bool clearwait = false; + sigpacket *q; + q = &sigq.start; + bool clearwait; + clearwait = false; switch (pack.si.si_signo) { case __SIGCOMMUNE: @@ -1482,6 +1479,7 @@ wait_sig (VOID *) } if (clearwait && !have_execed) proc_subproc (PROC_CLEARWAIT, 0); +skip_process_signal: if (pack.wakeup) { sigproc_printf ("signalling pack.wakeup %p", pack.wakeup); -- 2.33.0