From patchwork Fri Mar 14 15:19:35 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michal Luczaj X-Patchwork-Id: 14017044 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 D31F61FFC50; Fri, 14 Mar 2025 15:20:40 +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=1741965643; cv=none; b=hlL0U+9QjCPec7GZl+P85hK8A2Z3UOyBqYXcIGviJEeqrzcLtAcKmxvxxmOykSxqU87IW7PsCvhRIxJLJKIECLmZNSEf5PdcdFFIxt9ul4WwINMiTiEMlxtg2Pg1vdqsfg1BgglTbUwJ6TuS0IdjVa5mxp1tvxtTp53T/yAhW5Y= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741965643; c=relaxed/simple; bh=L+KTJGvZZL6WNwZ6CkOfjghyQtuOOIuC3o33rScf4Sk=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=ndiYMlmRGIOkW5sCVS40XEXRV9TCgBP0wYeHebeabHvi2NN9RC17dbFx1P44fuU3Kh6vJrlsRM3gCVPHNvYxjwKFpYtvj9KKobV20F3In4Js6ePxHmF73g8ThD4+OPWU1k8IDguajVIoUq76SJ+wNp/WRtiDWCX/P88MLW8jlfY= 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=SyABiwyg; 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="SyABiwyg" Received: from mailtransmit02.runbox ([10.9.9.162] 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 1tt6pt-006FJv-7C; Fri, 14 Mar 2025 16:20:33 +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=75aQS4EfbBkL1uqPvlHJ3IbPh6aVg1PW4sCCjIyt6CQ=; b=SyABiwyg3y0nW0o10MYkGiGD+7 28/m8lG0cfTxXOSaZbC3zjJSVTvxQzl1BsznqpICN5TSaPSP4/rSE7YMT4rktiKA3W1DLaN+pDE33 hdbUoBcI6pIGsY9FQGA0mtT5RV6Vs1h0NCQB6o98XpXLqNQU49SRmFP8bnMDGfEl3qPRM3/YugacX b44w1uj9GMxNHycB+OXP76Pxq3/wP7DyDw7pVSoS/nZJV71X5DAoD9TKi46OwZgweOkUaAtRohfCG O9D7AGM4gjVJkwr9MavKK2nbdmHDLAnnTRyZfeTL96sAYZdXf2yNKflX0L91JBQZoCSnJh8zJApK2 8jRC7Nrw==; Received: from [10.9.9.73] (helo=submission02.runbox) by mailtransmit02.runbox with esmtp (Exim 4.86_2) (envelope-from ) id 1tt6pn-0007cc-H8; Fri, 14 Mar 2025 16:20:27 +0100 Received: by submission02.runbox with esmtpsa [Authenticated ID (604044)] (TLS1.2:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.93) id 1tt6pc-00H06E-2g; Fri, 14 Mar 2025 16:20:16 +0100 From: Michal Luczaj Date: Fri, 14 Mar 2025 16:19:35 +0100 Subject: [PATCH net v2 2/3] selftest/bpf: Add test for AF_VSOCK connect() racing sockmap update Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20250314-vsock-trans-signal-race-v2-2-421a41f60f42@rbox.co> References: <20250314-vsock-trans-signal-race-v2-0-421a41f60f42@rbox.co> In-Reply-To: <20250314-vsock-trans-signal-race-v2-0-421a41f60f42@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 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 | 111 +++++++++++++++++++++ 1 file changed, 111 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..5c278353a924294a1452f650634cec0539804b1a 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 +1043,114 @@ 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; + } + + pthread_testcancel(); + } + + pthread_cleanup_pop(1); + + return NULL; +} + +static void test_sockmap_vsock_connect_signal_race(void) +{ + struct sockaddr_vm addr = { + .svm_family = AF_VSOCK, + .svm_cid = VMADDR_CID_LOCAL, + .svm_port = VMADDR_PORT_ANY + }; + struct sockaddr_vm bad_addr; + sighandler_t orig_handler; + pthread_t thread; + socklen_t alen; + 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; + + alen = sizeof(addr); + if (xgetsockname(s, (struct sockaddr *)&addr, &alen) < 0) + 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) + goto retry; + + if (!connect(c, (struct sockaddr *)&bad_addr, alen) || + errno != ESOCKTNOSUPPORT) + goto retry; + + if ((recv(c, &(char){0}, 1, MSG_DONTWAIT) < 0) && + errno == ENODEV) { + FAIL_ERRNO("recv"); + tout = 0; + } +retry: + 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 +1217,6 @@ 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(); }