From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yw1-f169.google.com (mail-yw1-f169.google.com [209.85.128.169]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F3B954C2247 for ; Mon, 5 Oct 2026 15:10:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.169 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791213006; cv=none; b=KOj1xu1E8H0aZKMT5MzOOu8ffB/XYGoVJR3KRYGmiMlxh2L3zuhblu6UPY1vXilzC2acSTznwevn+A3ltJDxQBMp/u2eGWfRFbXR21gsEwpL6aFe/zTIXU/ye6KhQl2aYF6CCZ8jOQs2q70S56lfeDrgC+T1IjNrUPtL18Du9Wc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791213006; c=relaxed/simple; bh=sj6IvvpiH4G5HeXtQ/w8rgZEYm6Vebo2GQ/VGeptjoQ=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=REEs9AQ39ds7LNCuDazmYk9UvzYhSEIidMWkhjpJONB4uXwwdktU/Pmm2z5Mdh4jSIcUZOEzXwb0nWG3s5s9K7GpVgcfQDcJdsR6p4VegZuHD0MGWBe+7HlJo+j/9d4om/nTY0fIRicHMqBLPtdb3ScWPUH/aRBPAydZHurnsbg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=amutable.com; spf=pass smtp.mailfrom=amutable.com; dkim=pass (2048-bit key) header.d=amutable-com.20251104.gappssmtp.com header.i=@amutable-com.20251104.gappssmtp.com header.b=00kxn9kE; arc=none smtp.client-ip=209.85.128.169 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=amutable.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=amutable.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=amutable-com.20251104.gappssmtp.com header.i=@amutable-com.20251104.gappssmtp.com header.b="00kxn9kE" Received: by mail-yw1-f169.google.com with SMTP id 00721157ae682-8ac525c1f05so16175807b3.1 for ; Mon, 05 Oct 2026 08:10:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amutable-com.20251104.gappssmtp.com; s=20251104; t=1791212999; x=1791817799; darn=vger.kernel.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :content-type:mime-version:subject:date:from:from:to:cc:subject:date :message-id:reply-to:content-type; bh=OiZ06e1bwcFWfpqrqmzoNBYBcxZ/+ZVmZd6FQIzN/qM=; b=00kxn9kE3vGTHtl3bKE8JrlY8b1mc/tt6MK3NzlWUmXSjEwgMtwbmTrv8kmJf3fzEb U7wuDL1ptAf6j3Ea+P/peJnhnXRzK/IbPIFNVvRJEd/7PlEg/A5C1rddBp3t6UCIUKtu X5BFR5C8lkP2VjvAg38calf5QJD70Cb2/0mDa9xyhgRfB38NZRqbKjXVQG7ViVE+Vr8l 62psLmdkXu1b8miz5uNvIBGibmsi+ul6v5uU6nQAwGXU5xjCLLFiWAheUkYCp/ti1wCv zBqd8opwdrJuDrvOUODIPx4zc+R6+VhM0qj0MV2seu/Q+wAVXyZwfYDIcTtUzcBjx+zm KGTQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1791212999; x=1791817799; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :content-type:mime-version:subject:date:from:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=OiZ06e1bwcFWfpqrqmzoNBYBcxZ/+ZVmZd6FQIzN/qM=; b=Z0ybxPdyhNqK5Blca3jLh0UP/pXYxt3PC51nB7beDI62Rq5EqoD6SnsTw/IfgqpwDm 4N9j47VIWtf9yPehMicWgyH2o5liPKvLm0tw3QbzwItMQayHdiIpEMNw0HVFwiNITuzf DnypasEMGorcgtcN2hV6IRVxKFKVHTtmS5bPdHB0UQV9walDeLD6tza+kmwhznTvMrt3 ep1R1idtc/t/sKayd9u0/FjSdEa+zGk6899XAyCEsIzcF01KTzQNTSjF6E0I35AeZKhB YNodxSk7MB4wPIIHiq0Vo+LGYMLXH57wBJ7pM7eRcF0XdPhlEYW5jrrpDzPslxJsYHcj ylKA== X-Forwarded-Encrypted: i=1; AKwUvBxduLDss2WanpAR0svIc7z/8bqmvp7vU+b00CKNYQFhmdXuA3RjVkmU54xVGxJmgyExnEvJvt6J/67mp20=@vger.kernel.org X-Gm-Message-State: AFq9FYJw0lhsoe/0s7O+4rmUajsaYvCxSYCbTCJPO/etDsd78NMpdNwP 5h+1Ge6nb9qu4B1gNCtSMEN8iisguVjIIslNUsR9YaI/ldzXuzgbSyGZEHieQANxzUjs X-Gm-Gg: AYBFou3DCEbKsshsAeG0AKUiocV2hGWTHfvLEdkI0y8Gsk15IUCldt1WYWLptUQa67Y dxSksNelfplw+uG/zFTI1mWKMeI4zqiI1JlM/BSEEUoLdKT4d53k5pSXplsSZ04QhBz//E8V2Sa kxO8QAojc9mBcm+Q3KTcijFGbBtW+TyfHOdAOMHARM4V1zeXW7pg6MnXghBtsEe0anhE+d9qVZL CIZftk312hvFM8tPBuZ8golz/PIgqVmzs857g9unOyuhDx4OzUVQzsNoq8uRcG5y6fQI3cYZ9Qn HfnwOOiW2tPk8P6VttSNubMGq+rSnR0q0N4y90oyf3JSOSE/ZwqO1OkiYc+tz9JNoxeYGSn3T9h +F+sUhHum/TQIhVpDPL1oXBorh55UtwTITtl/tTvjJTWM9xX/IO0KlID7JbWuZno1m5VAVMyTyz i4E8215tCY2+FQgpGxboFcDHF5idlAtf4Gf/nOc6X1UEolxaAYdP8gBM/PHZNXDogg5XxXi+lYf SeYd4c5Xd/g/jlgBxzorMWaTDNftUXS14yhYoVx/NRYOW86oOzulNiU X-Received: by 2002:a05:690c:4d49:b0:8ac:46ff:d3a5 with SMTP id 00721157ae682-8ae959d6dc1mr29681427b3.64.1791212998716; Mon, 05 Oct 2026 08:09:58 -0700 (PDT) Received: from [192.168.1.110] (104-53-165-62.lightspeed.stlsmo.sbcglobal.net. [104.53.165.62]) by smtp.gmail.com with ESMTPSA id 00721157ae682-8ae33fe81fdsm41210467b3.47.2026.10.05.08.09.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 05 Oct 2026 08:09:58 -0700 (PDT) From: Andrew Halaney Date: Mon, 05 Oct 2026 10:09:38 -0500 Subject: [PATCH v4 08/10] selftests/net: SO_PEERPIDFD_THREAD Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20261005-work-unix-passpidfd-v4-8-350183b6e02a@amutable.com> References: <20261005-work-unix-passpidfd-v4-0-350183b6e02a@amutable.com> In-Reply-To: <20261005-work-unix-passpidfd-v4-0-350183b6e02a@amutable.com> To: Jakub Kicinski , Kuniyuki Iwashima , Oleg Nesterov Cc: "David S. Miller" , Paolo Abeni , Simon Horman , Willem de Bruijn , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Alexander Viro , Jan Kara , linux-fsdevel@vger.kernel.org, Alexander Mikhalitsyn , "Christian Brauner (Amutable)" , Andrew Halaney , Eric Dumazet , Alexander Mikhalitsyn X-Mailer: b4 0.14.3 From: Christian Brauner Add tests for SO_PEERPIDFD_THREAD. Signed-off-by: Christian Brauner (Amutable) Reviewed-by: Alexander Mikhalitsyn Signed-off-by: Andrew Halaney --- tools/testing/selftests/net/af_unix/scm_pidfd.c | 97 +++++++++++++++++++++++++ 1 file changed, 97 insertions(+) diff --git a/tools/testing/selftests/net/af_unix/scm_pidfd.c b/tools/testing/selftests/net/af_unix/scm_pidfd.c index d73ae9d27a48..cbe53fab44fc 100644 --- a/tools/testing/selftests/net/af_unix/scm_pidfd.c +++ b/tools/testing/selftests/net/af_unix/scm_pidfd.c @@ -36,6 +36,10 @@ #define SO_PASSPIDFD_THREAD 86 #endif +#ifndef SO_PEERPIDFD_THREAD +#define SO_PEERPIDFD_THREAD 87 +#endif + #define CHILD_EXIT_CODE_OK 123 static void child_die() @@ -1058,4 +1062,97 @@ TEST(scm_pidfd_thread_creds) EXPECT_EQ(msg.ids.pid, msg.thread_info.tgid); } +static void *peer_connect_thread(void *arg) +{ + struct sock_addr *sa = arg; + struct thread_ids ids = { + .pid = getpid(), + .tid = gettid(), + }; + int fd; + char sync; + + fd = socket(AF_UNIX, SOCK_STREAM, 0); + if (fd < 0) + return (void *)1; + + if (connect(fd, (struct sockaddr *)&sa->listen_addr, sa->addrlen)) + return (void *)1; + + if (send(fd, &ids, sizeof(ids), 0) != sizeof(ids)) + return (void *)1; + + /* stay alive until the server has looked at our pidfd */ + if (read(fd, &sync, 1) != 1) + return (void *)1; + + close(fd); + return NULL; +} + +static int peer_pidfd_info(int fd, int optname, struct pidfd_info *info) +{ + int pidfd; + socklen_t len = sizeof(pidfd); + + if (getsockopt(fd, SOL_SOCKET, optname, &pidfd, &len)) { + log_err("getsockopt(SO_PEERPIDFD*)"); + return -1; + } + + info->mask = PIDFD_INFO_PID; + if (ioctl(pidfd, PIDFD_GET_INFO, info)) { + log_err("ioctl(PIDFD_GET_INFO)"); + close(pidfd); + return -1; + } + + close(pidfd); + return 0; +} + +/* SO_PEERPIDFD_THREAD returns a pidfd for the peer's connecting thread. */ +TEST(so_peerpidfd_thread) +{ + struct sock_addr sa; + struct thread_ids ids; + struct pidfd_info info; + pthread_t thread; + void *tret; + int server, cfd; + + server = socket(AF_UNIX, SOCK_STREAM, 0); + ASSERT_LE(0, server); + + fill_sockaddr(&sa, true); + ASSERT_EQ(0, bind(server, (struct sockaddr *)&sa.listen_addr, sa.addrlen)); + ASSERT_EQ(0, listen(server, 1)); + + ASSERT_EQ(0, pthread_create(&thread, NULL, peer_connect_thread, &sa)); + + cfd = accept(server, NULL, NULL); + ASSERT_LE(0, cfd); + + ASSERT_EQ(sizeof(ids), recv(cfd, &ids, sizeof(ids), MSG_WAITALL)); + ASSERT_NE(ids.pid, ids.tid); + + /* SO_PEERPIDFD refers to the peer's thread-group. */ + ASSERT_EQ(0, peer_pidfd_info(cfd, SO_PEERPIDFD, &info)); + EXPECT_EQ(ids.pid, info.pid); + EXPECT_EQ(ids.pid, info.tgid); + + /* SO_PEERPIDFD_THREAD refers to the connecting thread. */ + ASSERT_EQ(0, peer_pidfd_info(cfd, SO_PEERPIDFD_THREAD, &info)); + EXPECT_EQ(ids.tid, info.pid); + EXPECT_EQ(ids.pid, info.tgid); + + /* release the connecting thread */ + ASSERT_EQ(1, write(cfd, "x", 1)); + ASSERT_EQ(0, pthread_join(thread, &tret)); + ASSERT_EQ(NULL, tret); + + close(cfd); + close(server); +} + TEST_HARNESS_MAIN -- 2.55.0