From patchwork Sun Mar 16 22:45:07 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michal Luczaj X-Patchwork-Id: 14018547 X-Patchwork-Delegate: kuba@kernel.org Received: from mailtransmit05.runbox.com (mailtransmit05.runbox.com [185.226.149.38]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DBD781A0728; Sun, 16 Mar 2025 22:46:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.226.149.38 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742165176; cv=none; b=s1I5Vo2+lhhNVbSzc4AfAAv9OkSbmYWEv4z+Gy215GdhnsU/82lGE+i/mmmU/Z87zwvTl2vSz+EnUQkJRzQK/7PqD/Jy+jJylDat6s1dUB72YcM3pKRIrNK5jzsePo8D9hDG8iUaMHjECSj+CS5v+Q6nI84gODsUE8ULTk/35Yg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742165176; c=relaxed/simple; bh=0Vuf4A7KemEmnxE1amJ/cuggcFCMtABwslfDy2lyxls=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=j0AITSBEYf+Gx24MaWoj0Ls45gniJkbbKvBUz1WLpgC0y91iS2lAbmAA5rGSEYO2CVIsJ5zKh7OWnEWsKoX6Vxl5c1LUzcbhvsuUbBPTBsE+HO9TKVhD2Tw7kGZqnZYHnQRTeH3RmsOfgTcx496Z5AJweFa7Jfk/htEaSKzHTDE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=rbox.co; spf=pass smtp.mailfrom=rbox.co; dkim=pass (2048-bit key) header.d=rbox.co header.i=@rbox.co header.b=aQOdWHZD; arc=none smtp.client-ip=185.226.149.38 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=rbox.co Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rbox.co Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=rbox.co header.i=@rbox.co header.b="aQOdWHZD" Received: from mailtransmit03.runbox ([10.9.9.163] helo=aibo.runbox.com) by mailtransmit05.runbox.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.93) (envelope-from ) id 1ttwkE-00CYQb-Fz; Sun, 16 Mar 2025 23:46:10 +0100 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=rbox.co; s=selector1; h=Cc:To:In-Reply-To:References:Message-Id: Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date:From; bh=Ju1FMTCjLE06/FL0/l7ykej6UKINCh4tTv7Js5hjLtQ=; b=aQOdWHZDgzVbdI2DzUXvS+cZzr uKm0rSnpFbjeClXOTir8h3uGMpDFMDFtj4Mdua1Yfmt3rX0e1PbtkdPNBZQkiVO+fw5G5n+fOqk6j yhFPSUq1sKW/3UnlFfZgXj9OEBtZgJdazlvidi9Rpd16BNBTQnOfhUojTiCisGb08WMMW1C/betba Qp6uD0M+SDmU5J0RQ6tKgQdZmfXfidbgAcS7EOAmYXM+WIkcUFFHsBkSyRsXYCgWMH6ljCE5zQ5MR eHOlj48kk3aA0w1mwKE0cNfht84TixosaQvZEpREFspXFvLO5mbHd3Y4BZOv5+uImlLKQ6HyybSSV d9YiacmA==; Received: from [10.9.9.74] (helo=submission03.runbox) by mailtransmit03.runbox with esmtp (Exim 4.86_2) (envelope-from ) id 1ttwkE-0000fn-4V; Sun, 16 Mar 2025 23:46:10 +0100 Received: by submission03.runbox with esmtpsa [Authenticated ID (604044)] (TLS1.2:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.93) id 1ttwjq-00AYw2-Eh; Sun, 16 Mar 2025 23:45:46 +0100 From: Michal Luczaj Date: Sun, 16 Mar 2025 23:45:07 +0100 Subject: [PATCH net v3 2/3] selftest/bpf: Add test for AF_VSOCK connect() racing sockmap update Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20250316-vsock-trans-signal-race-v3-2-17a6862277c9@rbox.co> References: <20250316-vsock-trans-signal-race-v3-0-17a6862277c9@rbox.co> In-Reply-To: <20250316-vsock-trans-signal-race-v3-0-17a6862277c9@rbox.co> To: Stefano Garzarella , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , "Michael S. Tsirkin" , Bobby Eshleman , Andrii Nakryiko , Eduard Zingerman , Mykola Lysenko , Alexei Starovoitov , Daniel Borkmann , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Shuah Khan Cc: netdev@vger.kernel.org, bpf@vger.kernel.org, virtualization@lists.linux.dev, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, Michal Luczaj X-Mailer: b4 0.14.2 X-Patchwork-Delegate: kuba@kernel.org Racing signal-interrupted connect() and sockmap update may result in an unconnected (and missing vsock transport) socket in a sockmap. Test spends 2 seconds attempting to reach WARN_ON_ONCE(). connect / state = SS_CONNECTED / sock_map_update_elem if signal_pending state = SS_UNCONNECTED connect transport = NULL vsock_bpf_recvmsg WARN_ON_ONCE(!vsk->transport) Signed-off-by: Michal Luczaj --- .../selftests/bpf/prog_tests/sockmap_basic.c | 97 ++++++++++++++++++++++ 1 file changed, 97 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c b/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c index 1e3e4392dcca0e1722c1982ecc649a80c27443b2..d9cd20d1fbc25cc56d37f06522c5b805004fa884 100644 --- a/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c +++ b/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c @@ -3,6 +3,7 @@ #include #include #include +#include #include "test_progs.h" #include "test_skmsg_load_helpers.skel.h" @@ -1042,6 +1043,100 @@ static void test_sockmap_vsock_unconnected(void) xclose(map); } +#define CONNECT_SIGNAL_RACE_TIMEOUT 2 /* seconds */ + +static void sig_handler(int signum) +{ + /* nop */ +} + +static void connect_signal_racer_cleanup(void *map) +{ + xclose(*(int *)map); +} + +static void *connect_signal_racer(void *arg) +{ + int map; + + map = bpf_map_create(BPF_MAP_TYPE_SOCKMAP, NULL, sizeof(int), + sizeof(int), 1, NULL); + if (!ASSERT_OK_FD(map, "bpf_map_create")) + return NULL; + + pthread_cleanup_push(connect_signal_racer_cleanup, &map); + + for (;;) { + int c = *(int *)arg; + int zero = 0; + + (void)bpf_map_update_elem(map, &zero, &c, BPF_ANY); + + if (kill(0, SIGUSR1)) { + FAIL_ERRNO("kill"); + break; + } + + if ((recv(c, NULL, 0, MSG_DONTWAIT) < 0) && errno == ENODEV) { + FAIL_ERRNO("recv"); + break; + } + } + + pthread_cleanup_pop(1); + + return NULL; +} + +static void test_sockmap_vsock_connect_signal_race(void) +{ + struct sockaddr_vm addr, bad_addr; + socklen_t alen = sizeof(addr); + sighandler_t orig_handler; + pthread_t thread; + int s, c, p; + __u64 tout; + + orig_handler = signal(SIGUSR1, sig_handler); + if (!ASSERT_NEQ(orig_handler, SIG_ERR, "signal handler setup")) + return; + + s = socket_loopback(AF_VSOCK, SOCK_SEQPACKET | SOCK_NONBLOCK); + if (s < 0) + goto restore; + + if (xgetsockname(s, (struct sockaddr *)&addr, &alen)) + goto close; + + bad_addr = addr; + bad_addr.svm_cid = 0x42424242; /* non-existing */ + + if (xpthread_create(&thread, 0, connect_signal_racer, &c)) + goto close; + + tout = get_time_ns() + CONNECT_SIGNAL_RACE_TIMEOUT * NSEC_PER_SEC; + do { + c = xsocket(AF_VSOCK, SOCK_SEQPACKET, 0); + if (c < 0) + break; + + if (connect(c, (struct sockaddr *)&addr, alen) && errno == EINTR) + (void)connect(c, (struct sockaddr *)&bad_addr, alen); + + xclose(c); + p = accept(s, NULL, NULL); + if (p >= 0) + xclose(p); + } while (get_time_ns() < tout); + + ASSERT_OK(pthread_cancel(thread), "pthread_cancel"); + xpthread_join(thread, NULL); +close: + xclose(s); +restore: + ASSERT_NEQ(signal(SIGUSR1, orig_handler), SIG_ERR, "handler restore"); +} + void test_sockmap_basic(void) { if (test__start_subtest("sockmap create_update_free")) @@ -1108,4 +1203,6 @@ void test_sockmap_basic(void) test_sockmap_skb_verdict_vsock_poll(); if (test__start_subtest("sockmap vsock unconnected")) test_sockmap_vsock_unconnected(); + if (test__start_subtest("sockmap vsock connect signal race")) + test_sockmap_vsock_connect_signal_race(); }