From patchwork Sat Feb 3 12:26:01 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13544214 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 A5E11C4828F for ; Sat, 3 Feb 2024 12:35:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:In-Reply-To:References:Message-Id :MIME-Version:Subject:Date:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=dgjHWJGPEYijyaDINt1o3NKhHGTkHlNYLDOfQ2tDh7o=; b=ejOd1xM+viY2ts l9XaVNmMsAgC7lYfdIHQModUwt+jOVVytDe+yy6rhLIO3vaAKb8yAeChz2AiX+2eJBJADz5xT4B/C At4Kmkq0IzXNtIrNQTOrWhTCU4HpUf8HsDWy47iR8I/uDS8lmCpYDRgYrAa0iM69W/B2S6uH0YcMB TlQPD/b0vFqgpIh+06SoQJsVpA8jFtuHHSwWO6EKmq0u88yc/T+b5F7CuqvP2E5z7ublpcvgCNq3K rLi260g2hgx83CQaYso4MBMKD90tf6HKyKQpENhSgeSdsSbSxuQIQ+RzlUCPb+p5HKev01+vqgHTs FJPot/uyIOytVCuMvFpQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rWFEk-0000000GMbl-0hQh; Sat, 03 Feb 2024 12:35:10 +0000 Received: from desiato.infradead.org ([2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rWFDn-0000000GLhe-04yz; Sat, 03 Feb 2024 12:34:11 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Cc:To:In-Reply-To:References: Message-Id:Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date: From:Sender:Reply-To:Content-ID:Content-Description; bh=Q63bLDXkh15yQCdV0K5VqiZFNax7wobma8vbysoaWMs=; b=p2SA0+MGc1jJOQzm7hT/+gIPMZ tetmvcg/hxDAknGnJ7CoPP08OZM3Wc3vyVH5BzJwQD8oPc9SeaXCW8LPdEwfw6EukZLE8S/pMVPbF uCAstSkedMUc8nok/XljSC/7USE3wSASNkRr3zWEu9Jo+bfEWcA/QSFEMTMccRMPxNqe8QmvwVW7z qEG96KqUA3k+ILKrtM/o44v852iX/9HBWAfRNnWHZM6yIt7p5cQ86tTIBzprzkXBsxtumefmsoAbJ mp9LkoMoH8cp0vvYwuEBkas7jnE6FU2/tc/LQwL1shET43NBTxlzusIrPg24BUJfsqzMUXvqYAcV9 A1jUpvFQ==; Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by desiato.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rWFDK-0000000All6-3g7y; Sat, 03 Feb 2024 12:34:07 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 7C3116069B; Sat, 3 Feb 2024 12:33:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E16E0C433F1; Sat, 3 Feb 2024 12:33:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1706963621; bh=29MX4bFmi9RjszKvoThz75zOXEvMrbFZDv9wXNIm3c0=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=ou0+iCIHrfjXH8n3BCVtgt+iHJGGPftd3xtuxNQzXoESJCfCMvhUTf2x5E3rIuQXp Z7X1iVJst836kXKlagMfIlHB4EcQHl98pVo+QfyapUl9k537WYC6jKYvmBdZ8DuN4f swOLANkxDyBQO5rIaFMOPmeBkOOw6DHQ5/dWVmyJQJp3QN0dHZiqNYA1k3g+1/5HUb wikHa/mQQOEtYIMALYfqVSNvwK7Z7N4PoorqEccGi2S8fK3zwpvpkHwGYd7sUz7j0D IXCHps1tEZxuErKWv1XBKO/0kQVm6GNTaiMdxIaPagWkxXQwm+PO85dzIyxITFNfFD TgmaqF/7+K36g== From: Mark Brown Date: Sat, 03 Feb 2024 12:26:01 +0000 Subject: [PATCH v8 35/38] selftests/arm64: Add GCS signal tests MIME-Version: 1.0 Message-Id: <20240203-arm64-gcs-v8-35-c9fec77673ef@kernel.org> References: <20240203-arm64-gcs-v8-0-c9fec77673ef@kernel.org> In-Reply-To: <20240203-arm64-gcs-v8-0-c9fec77673ef@kernel.org> To: Catalin Marinas , Will Deacon , Jonathan Corbet , Andrew Morton , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Arnd Bergmann , Oleg Nesterov , Eric Biederman , Kees Cook , Shuah Khan , "Rick P. Edgecombe" , Deepak Gupta , Ard Biesheuvel , Szabolcs Nagy Cc: "H.J. Lu" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Florian Weimer , Christian Brauner , Thiago Jung Bauermann , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, kvmarm@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, Mark Brown X-Mailer: b4 0.13-dev-a684c X-Developer-Signature: v=1; a=openpgp-sha256; l=7609; i=broonie@kernel.org; h=from:subject:message-id; bh=29MX4bFmi9RjszKvoThz75zOXEvMrbFZDv9wXNIm3c0=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBlvjDsC+adCQ5LH7Db6WhjtpyGz4I1K5rQocla/DSr j0dGSSyJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZb4w7AAKCRAk1otyXVSH0Eh4B/ 9VPWk1n8iVrCOX/tNVqSxjuteZ6BZ4SFxLj1NSvlrss8g9uHuY3fK+z7N8fegHs6CpMUqAp5Ps4noG T4tDEHp1kDKvUgiKBiVS/th0nhCtsneRDl884ghHbL+4WQ3Y9i1VA+bGTN6+/AcTuHtst3o84jo4SX f9Yxd4zSCAFbTw6hOzwQKUbzkj32Xtj9V05+803T5/Tbq0j6cSrjLqzF10edbtBlDaHE7owmUzqKvm 6IhK3sBOJrT7uwbvUzBqfobQza7tQY9E2LBIzVe7WG1yqVOkKxRh0x6kji2WRdMCkL+evutA5AC/in +eWj3fFSAwg70jXfu4I5F02Wt9/uK7 X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240203_123347_228369_FDF4CE20 X-CRM114-Status: GOOD ( 21.18 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Do some testing of the signal handling for GCS, checking that a GCS frame has the expected information in it and that the expected signals are delivered with invalid operations. Signed-off-by: Mark Brown --- tools/testing/selftests/arm64/signal/.gitignore | 1 + .../selftests/arm64/signal/test_signals_utils.h | 10 +++ .../arm64/signal/testcases/gcs_exception_fault.c | 62 +++++++++++++++ .../selftests/arm64/signal/testcases/gcs_frame.c | 88 ++++++++++++++++++++++ .../arm64/signal/testcases/gcs_write_fault.c | 67 ++++++++++++++++ 5 files changed, 228 insertions(+) diff --git a/tools/testing/selftests/arm64/signal/.gitignore b/tools/testing/selftests/arm64/signal/.gitignore index 839e3a252629..26de12918890 100644 --- a/tools/testing/selftests/arm64/signal/.gitignore +++ b/tools/testing/selftests/arm64/signal/.gitignore @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0-only mangle_* fake_sigreturn_* +gcs_* sme_* ssve_* sve_* diff --git a/tools/testing/selftests/arm64/signal/test_signals_utils.h b/tools/testing/selftests/arm64/signal/test_signals_utils.h index 1e80808ee105..36fc12b3cd60 100644 --- a/tools/testing/selftests/arm64/signal/test_signals_utils.h +++ b/tools/testing/selftests/arm64/signal/test_signals_utils.h @@ -6,6 +6,7 @@ #include #include +#include #include #include @@ -47,6 +48,15 @@ void test_result(struct tdescr *td); _arg1; \ }) +static inline __attribute__((always_inline)) uint64_t get_gcspr_el0(void) +{ + uint64_t val; + + asm volatile("mrs %0, S3_3_C2_C5_1" : "=r" (val)); + + return val; +} + static inline bool feats_ok(struct tdescr *td) { if (td->feats_incompatible & td->feats_supported) diff --git a/tools/testing/selftests/arm64/signal/testcases/gcs_exception_fault.c b/tools/testing/selftests/arm64/signal/testcases/gcs_exception_fault.c new file mode 100644 index 000000000000..6228448b2ae7 --- /dev/null +++ b/tools/testing/selftests/arm64/signal/testcases/gcs_exception_fault.c @@ -0,0 +1,62 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2023 ARM Limited + */ + +#include +#include +#include + +#include +#include + +#include "test_signals_utils.h" +#include "testcases.h" + +/* + * We should get this from asm/siginfo.h but the testsuite is being + * clever with redefining siginfo_t. + */ +#ifndef SEGV_CPERR +#define SEGV_CPERR 10 +#endif + +static inline void gcsss1(uint64_t Xt) +{ + asm volatile ( + "sys #3, C7, C7, #2, %0\n" + : + : "rZ" (Xt) + : "memory"); +} + +static int gcs_op_fault_trigger(struct tdescr *td) +{ + /* + * The slot below our current GCS should be in a valid GCS but + * must not have a valid cap in it. + */ + gcsss1(get_gcspr_el0() - 8); + + return 0; +} + +static int gcs_op_fault_signal(struct tdescr *td, siginfo_t *si, + ucontext_t *uc) +{ + ASSERT_GOOD_CONTEXT(uc); + + return 1; +} + +struct tdescr tde = { + .name = "Invalid GCS operation", + .descr = "An invalid GCS operation generates the expected signal", + .feats_required = FEAT_GCS, + .timeout = 3, + .sig_ok = SIGSEGV, + .sig_ok_code = SEGV_CPERR, + .sanity_disabled = true, + .trigger = gcs_op_fault_trigger, + .run = gcs_op_fault_signal, +}; diff --git a/tools/testing/selftests/arm64/signal/testcases/gcs_frame.c b/tools/testing/selftests/arm64/signal/testcases/gcs_frame.c new file mode 100644 index 000000000000..b405d82321da --- /dev/null +++ b/tools/testing/selftests/arm64/signal/testcases/gcs_frame.c @@ -0,0 +1,88 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2023 ARM Limited + */ + +#include +#include +#include + +#include "test_signals_utils.h" +#include "testcases.h" + +static union { + ucontext_t uc; + char buf[1024 * 64]; +} context; + +static int gcs_regs(struct tdescr *td, siginfo_t *si, ucontext_t *uc) +{ + size_t offset; + struct _aarch64_ctx *head = GET_BUF_RESV_HEAD(context); + struct gcs_context *gcs; + unsigned long expected, gcspr; + uint64_t *u64_val; + int ret; + + ret = prctl(PR_GET_SHADOW_STACK_STATUS, &expected, 0, 0, 0); + if (ret != 0) { + fprintf(stderr, "Unable to query GCS status\n"); + return 1; + } + + /* We expect a cap to be added to the GCS in the signal frame */ + gcspr = get_gcspr_el0(); + gcspr -= 8; + fprintf(stderr, "Expecting GCSPR_EL0 %lx\n", gcspr); + + if (!get_current_context(td, &context.uc, sizeof(context))) { + fprintf(stderr, "Failed getting context\n"); + return 1; + } + + /* Ensure that the signal restore token was consumed */ + u64_val = (uint64_t *)get_gcspr_el0() + 1; + if (*u64_val) { + fprintf(stderr, "GCS value at %p is %lx not 0\n", + u64_val, *u64_val); + return 1; + } + + fprintf(stderr, "Got context\n"); + + head = get_header(head, GCS_MAGIC, GET_BUF_RESV_SIZE(context), + &offset); + if (!head) { + fprintf(stderr, "No GCS context\n"); + return 1; + } + + gcs = (struct gcs_context *)head; + + /* Basic size validation is done in get_current_context() */ + + if (gcs->features_enabled != expected) { + fprintf(stderr, "Features enabled %llx but expected %lx\n", + gcs->features_enabled, expected); + return 1; + } + + if (gcs->gcspr != gcspr) { + fprintf(stderr, "Got GCSPR %llx but expected %lx\n", + gcs->gcspr, gcspr); + return 1; + } + + fprintf(stderr, "GCS context validated\n"); + td->pass = 1; + + return 0; +} + +struct tdescr tde = { + .name = "GCS basics", + .descr = "Validate a GCS signal context", + .feats_required = FEAT_GCS, + .timeout = 3, + .run = gcs_regs, +}; diff --git a/tools/testing/selftests/arm64/signal/testcases/gcs_write_fault.c b/tools/testing/selftests/arm64/signal/testcases/gcs_write_fault.c new file mode 100644 index 000000000000..faeabb18c4b2 --- /dev/null +++ b/tools/testing/selftests/arm64/signal/testcases/gcs_write_fault.c @@ -0,0 +1,67 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2023 ARM Limited + */ + +#include +#include +#include + +#include +#include + +#include "test_signals_utils.h" +#include "testcases.h" + +static uint64_t *gcs_page; + +#ifndef __NR_map_shadow_stack +#define __NR_map_shadow_stack 453 +#endif + +static bool alloc_gcs(struct tdescr *td) +{ + long page_size = sysconf(_SC_PAGE_SIZE); + + gcs_page = (void *)syscall(__NR_map_shadow_stack, 0, + page_size, 0); + if (gcs_page == MAP_FAILED) { + fprintf(stderr, "Failed to map %ld byte GCS: %d\n", + page_size, errno); + return false; + } + + return true; +} + +static int gcs_write_fault_trigger(struct tdescr *td) +{ + /* Verify that the page is readable (ie, not completely unmapped) */ + fprintf(stderr, "Read value 0x%lx\n", gcs_page[0]); + + /* A regular write should trigger a fault */ + gcs_page[0] = EINVAL; + + return 0; +} + +static int gcs_write_fault_signal(struct tdescr *td, siginfo_t *si, + ucontext_t *uc) +{ + ASSERT_GOOD_CONTEXT(uc); + + return 1; +} + + +struct tdescr tde = { + .name = "GCS write fault", + .descr = "Normal writes to a GCS segfault", + .feats_required = FEAT_GCS, + .timeout = 3, + .sig_ok = SIGSEGV, + .sanity_disabled = true, + .init = alloc_gcs, + .trigger = gcs_write_fault_trigger, + .run = gcs_write_fault_signal, +};