From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 0BE2822301; Thu, 16 Jul 2026 13:57:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784210244; cv=none; b=jW8pZLEsEsKAgZIEoKFeoq0YzMoao9/roXCPDNetuK8lGGc8IyKH6+oUm/bWDoS1HIax+Bp5VBTuTy2FknrNuPru2gAst6DCZMO5uA8wddTWMbzNWpyOqMAqru39xr69tN5Qga04EoeluIE8AVBeXyYSK5JZx5dRHm1+CC4mRzA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784210244; c=relaxed/simple; bh=W0QRMQGXBniCRTLBcywpeJ9FdH0kazi2jC9M9tc+oFw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=EFEcmxMUm3p2RoSjSmu2kcBsiKwbE+urtRbdE5dIoiXxAk1IRyjsUEtWlaaBrfDDs3ThrVho1DktloRPbNgVoQcd+Jwd5eFAmZ2M0qz4faCF/nAGT2NLibgHMyS3KMSQzsL35WVWfDUYJFdolQVSsrYUAI8WvXcVvc/7603Rj+w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=HWfmWlPn; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="HWfmWlPn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 727EB1F000E9; Thu, 16 Jul 2026 13:57:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784210242; bh=T+2WfNMQjbBkJtvSM40UAUnbp/kkFsXvkg1m28txXrI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=HWfmWlPn4uefEvyQDItbPZkmTL5nj1QZK39HW4jejIvt6Y849BBIxCQANM0fDlh03 2u6KDxONbsVbJRSvDNXO3TWIFzxmIDArS1ZabMNEOvTWd4k6Cmw1VfQRX0KD6VPyOF q05/WJP0dzSjXmvq/Xzw9GcOoeboOMZMfzVgve3k= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?G=C3=BCnther=20Noack?= , =?UTF-8?q?G=C3=BCnther=20Noack?= , =?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?= Subject: [PATCH 7.1 448/518] selftests/landlock: Filter dealloc records in audit_count_records() Date: Thu, 16 Jul 2026 15:31:56 +0200 Message-ID: <20260716133057.645448959@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260716133047.772246337@linuxfoundation.org> References: <20260716133047.772246337@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 7.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mickaël Salaün commit 26679fad81a471428707d2dd7b0418204c52b7e4 upstream. audit_count_records() counts both AUDIT_LANDLOCK_DOMAIN allocation and deallocation records in records.domain . Domain deallocation is tied to asynchronous credential freeing via kworker threads (landlock_put_ruleset_deferred), so the dealloc record can arrive after the drain in audit_init() and after the preceding audit_match_record() call. This causes flaky failures in tests that assert an exact records.domain count: a stale dealloc record from a previous test's domain inflates the count by one. Observed on x86_64 under build configurations that delay the kworker firing the dealloc callback (e.g. coverage instrumentation): the audit_layout1 tests in fs_test.c intermittently saw records.domain == 2 where 1 was expected. The fix is in the shared helper, so those existing checks become robust without needing a fs_test.c edit. Filter audit_count_records() with a regex to skip records containing deallocation status. The remaining domain records (allocation, emitted synchronously during landlock_log_denial()) are deterministic. Deallocation records are already tested explicitly via matches_log_domain_deallocated() in audit_test.c, which uses its own domain-ID-based filtering and longer timeout. With this filter in place, re-add the records.domain == 0 checks that were removed in commit 3647a4977fb7 ("selftests/landlock: Drain stale audit records on init") as a workaround for this race. Cc: Günther Noack Cc: stable@vger.kernel.org Depends-on: 07c2572a8757 ("selftests/landlock: Skip stale records in audit_match_record()") Fixes: 6a500b22971c ("selftests/landlock: Add tests for audit flags and domain IDs") Tested-by: Günther Noack Link: https://patch.msgid.link/20260513105112.140137-1-mic@digikod.net Signed-off-by: Mickaël Salaün Signed-off-by: Greg Kroah-Hartman --- tools/testing/selftests/landlock/audit.h | 39 +++++++---- tools/testing/selftests/landlock/audit_test.c | 2 tools/testing/selftests/landlock/ptrace_test.c | 1 tools/testing/selftests/landlock/scoped_abstract_unix_test.c | 1 4 files changed, 30 insertions(+), 13 deletions(-) --- a/tools/testing/selftests/landlock/audit.h +++ b/tools/testing/selftests/landlock/audit.h @@ -381,18 +381,24 @@ struct audit_records { }; /* - * WARNING: Do not assert records.domain == 0 without a preceding - * audit_match_record() call. Domain deallocation records are emitted - * asynchronously from kworker threads and can arrive after the drain in - * audit_init(), corrupting the domain count. A preceding audit_match_record() - * call consumes stale records while scanning, making the assertion safe in - * practice because stale deallocation records arrive before the expected access - * records. + * Counts remaining audit records by type, skipping domain deallocation records. + * Deallocation records are emitted asynchronously from kworker threads after a + * previous test's child has exited, so they can arrive after the drain in + * audit_init() and after the preceding audit_match_record() call. Allocation + * records are emitted synchronously during landlock_log_denial() in the current + * test's syscall context, so only those are counted in records->domain. */ static int audit_count_records(int audit_fd, struct audit_records *records) { + static const char dealloc_pattern[] = REGEX_LANDLOCK_PREFIX + " status=deallocated "; struct audit_message msg; - int err; + regex_t dealloc_re; + int ret, err = 0; + + ret = regcomp(&dealloc_re, dealloc_pattern, 0); + if (ret) + return -ENOMEM; records->access = 0; records->domain = 0; @@ -402,9 +408,8 @@ static int audit_count_records(int audit err = audit_recv(audit_fd, &msg); if (err) { if (err == -EAGAIN) - return 0; - else - return err; + err = 0; + break; } switch (msg.header.nlmsg_type) { @@ -412,12 +417,20 @@ static int audit_count_records(int audit records->access++; break; case AUDIT_LANDLOCK_DOMAIN: - records->domain++; + ret = regexec(&dealloc_re, msg.data, 0, NULL, 0); + if (ret == REG_NOMATCH) { + records->domain++; + } else if (ret != 0) { + err = -EIO; + goto out; + } break; } } while (true); - return 0; +out: + regfree(&dealloc_re); + return err; } static int audit_init(void) --- a/tools/testing/selftests/landlock/audit_test.c +++ b/tools/testing/selftests/landlock/audit_test.c @@ -730,6 +730,7 @@ TEST_F(audit_flags, signal) } else { EXPECT_EQ(1, records.access); } + EXPECT_EQ(0, records.domain); /* Updates filter rules to match the drop record. */ set_cap(_metadata, CAP_AUDIT_CONTROL); @@ -915,6 +916,7 @@ TEST_F(audit_exec, signal_and_open) /* Tests that there was no denial until now. */ EXPECT_EQ(0, audit_count_records(self->audit_fd, &records)); EXPECT_EQ(0, records.access); + EXPECT_EQ(0, records.domain); /* * Wait for the child to do a first denied action by layer1 and --- a/tools/testing/selftests/landlock/ptrace_test.c +++ b/tools/testing/selftests/landlock/ptrace_test.c @@ -342,6 +342,7 @@ TEST_F(audit, trace) /* Makes sure there is no superfluous logged records. */ EXPECT_EQ(0, audit_count_records(self->audit_fd, &records)); EXPECT_EQ(0, records.access); + EXPECT_EQ(0, records.domain); yama_ptrace_scope = get_yama_ptrace_scope(); ASSERT_LE(0, yama_ptrace_scope); --- a/tools/testing/selftests/landlock/scoped_abstract_unix_test.c +++ b/tools/testing/selftests/landlock/scoped_abstract_unix_test.c @@ -312,6 +312,7 @@ TEST_F(scoped_audit, connect_to_child) /* Makes sure there is no superfluous logged records. */ EXPECT_EQ(0, audit_count_records(self->audit_fd, &records)); EXPECT_EQ(0, records.access); + EXPECT_EQ(0, records.domain); ASSERT_EQ(0, pipe2(pipe_child, O_CLOEXEC)); ASSERT_EQ(0, pipe2(pipe_parent, O_CLOEXEC));