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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 81843C433EF for ; Sun, 19 Dec 2021 15:57:16 +0000 (UTC) Received: from localhost ([::1]:41518 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1myyYk-0003qV-UU for qemu-devel@archiver.kernel.org; Sun, 19 Dec 2021 10:57:14 -0500 Received: from eggs.gnu.org ([209.51.188.92]:50316) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1myyX7-00026N-Lv for qemu-devel@nongnu.org; Sun, 19 Dec 2021 10:55:35 -0500 Received: from mout.kundenserver.de ([217.72.192.74]:59747) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1myyX5-0004PM-SN for qemu-devel@nongnu.org; Sun, 19 Dec 2021 10:55:33 -0500 Received: from [192.168.100.1] ([82.142.30.186]) by mrelayeu.kundenserver.de (mreue108 [213.165.67.119]) with ESMTPSA (Nemesis) id 1MtwMc-1me9I91ZcK-00uJL6; Sun, 19 Dec 2021 16:55:17 +0100 Message-ID: <87c9f71f-ed9d-03e4-9a0e-594b649525b5@vivier.eu> Date: Sun, 19 Dec 2021 16:55:16 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.3.0 Subject: Re: [PATCH] linux-user/signal: Map exit signals in SIGCHLD siginfo_t Content-Language: fr To: qemu-devel@nongnu.org References: <81534fde7cdfc6acea4889d886fbefdd606630fb.1635019124.git.mschiffer@universe-factory.net> From: Laurent Vivier In-Reply-To: <81534fde7cdfc6acea4889d886fbefdd606630fb.1635019124.git.mschiffer@universe-factory.net> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Provags-ID: V03:K1:gTH7pc6Gt6fMjLsvhaiF/gEVb1clsh5UqB1j+llR+aos7ZnCih1 Myp49c4bDGtB/f5rAT+VXN48CCv9uIU0gOUkW6Um4doYOWHa9avw8zS1hReqzYKMSErlPm3 Hz7wv9zY0IthF5vcISRrXednHKdP410M99uLU+7FAH2ba46PnK++58plNJjXiczcmc6Lt88 4FWoKcNH5PquBG2/uggoA== X-UI-Out-Filterresults: notjunk:1;V03:K0:748EMlj/Uz0=:q+28O1UmWqQRNvpjNeLKwU GiWLhIDRqjBJ4dBux+U0aEDYB8igqv6gckKOJLvGOy3eFF+BR/iSdWM8bBYOhWAmPq8qgqYIN lZ4ds+JHsqgNprRYn7eBXr0saK4XJeIEAwaoVNYEaZfaVv9vw/9kq4+5Wos6OAmU75LITE5uY SgevVaPqJ6HYHgW+ZJNECeNrouAUap6EhcYlaLAoiTk4xmEQE51I9n0GLNGCzB8koYHr3Z+IZ scbzSK9ERZYTJaNakvLy1JxR2WyZaaKgDRFa4i5LrP58DW5hoMlW3S2rk+FcAY903mz7qdP6j lxAA7vjhsrw9Ak0RMRyKVeMALaOFqaKUQtH5XQvViCf7oxJEWLZrENlf87fUq1Ei3ZZdhZ8P3 mCA5bmXULmnJTtIqFLgSwM1mrBhSlIaxpzdpwLiXsnitWT1D4ow+S81D91W8LFspw1SD7kXB7 SkFVf2/3JBVV6RUKxbjg/cyM3bNrCf40YpjkFViqtel6bKVfB7feKNxlOr3r104KhY9yAODxT y+9G/guWi7GLYFp1AeB/VDu+iDheSkdDYQ9RIn9HzDres0JApP6uho3G9nrnqEqmwpCYhV8J/ PMgQtTXLLwxDWpTAiDNoBxM3u/gS2/yPyM4WMzxHxC1z2RiiRIX+SgvXCUaZ3qBjUztv7pHaw lGFU+38SJxKMimQQrin7D5/MIkT4FLpNZhoTS1LAlj+6yBT6w9qhHjRfR5PB8JMqEfTU= Received-SPF: none client-ip=217.72.192.74; envelope-from=laurent@vivier.eu; helo=mout.kundenserver.de X-Spam_score_int: -24 X-Spam_score: -2.5 X-Spam_bar: -- X-Spam_report: (-2.5 / 5.0 requ) BAYES_00=-1.9, NICE_REPLY_A=-0.563, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_NONE=0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: =?UTF-8?Q?Andreas_K=2e_H=c3=bcttel?= , Alistair Francis , Matthias Schiffer Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" CC'ing Alistair and Andreas that were involved in original fix 1c3dfb506ea3 ("linux-user/signal: Decode waitid si_code") Thanks, Laurent Le 23/10/2021 à 21:59, Matthias Schiffer a écrit : > When converting a siginfo_t from waitid(), the interpretation of si_status > depends on the value of si_code: For CLD_EXITED, it is an exit code and > should be copied verbatim. For other codes, it is a signal number > (possibly with additional high bits from ptrace) that should be mapped. > > This code was previously changed in commit 1c3dfb506ea3 > ("linux-user/signal: Decode waitid si_code"), but the fix was > incomplete. > > Tested with the following test program: > > #include > #include > #include > #include > > int main() { > pid_t pid = fork(); > if (pid == 0) { > exit(12); > } else { > siginfo_t siginfo = {}; > waitid(P_PID, pid, &siginfo, WEXITED); > printf("Code: %d, status: %d\n", (int)siginfo.si_code, (int)siginfo.si_status); > } > > pid = fork(); > if (pid == 0) { > raise(SIGUSR2); > } else { > siginfo_t siginfo = {}; > waitid(P_PID, pid, &siginfo, WEXITED); > printf("Code: %d, status: %d\n", (int)siginfo.si_code, (int)siginfo.si_status); > } > } > > Output with an x86_64 host and mips64el target before 1c3dfb506ea3 > (incorrect: exit code 12 is translated like a signal): > > Code: 1, status: 17 > Code: 2, status: 17 > > After 1c3dfb506ea3 (incorrect: signal number is not translated): > > Code: 1, status: 12 > Code: 2, status: 12 > > With this patch: > > Code: 1, status: 12 > Code: 2, status: 17 > > Signed-off-by: Matthias Schiffer > --- > linux-user/signal.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/linux-user/signal.c b/linux-user/signal.c > index 14d8fdfde152..8e3af98ec0a7 100644 > --- a/linux-user/signal.c > +++ b/linux-user/signal.c > @@ -403,7 +403,12 @@ static inline void host_to_target_siginfo_noswap(target_siginfo_t *tinfo, > case TARGET_SIGCHLD: > tinfo->_sifields._sigchld._pid = info->si_pid; > tinfo->_sifields._sigchld._uid = info->si_uid; > - tinfo->_sifields._sigchld._status = info->si_status; > + if (si_code == CLD_EXITED) > + tinfo->_sifields._sigchld._status = info->si_status; > + else > + tinfo->_sifields._sigchld._status > + = host_to_target_signal(info->si_status & 0x7f) > + | (info->si_status & ~0x7f); > tinfo->_sifields._sigchld._utime = info->si_utime; > tinfo->_sifields._sigchld._stime = info->si_stime; > si_type = QEMU_SI_CHLD; >