From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 66CE0C433FF for ; Tue, 6 Aug 2019 10:01:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3479520C01 for ; Tue, 6 Aug 2019 10:01:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="ryN6Ug8N" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732583AbfHFKBN (ORCPT ); Tue, 6 Aug 2019 06:01:13 -0400 Received: from mail-yw1-f67.google.com ([209.85.161.67]:36981 "EHLO mail-yw1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732585AbfHFKBM (ORCPT ); Tue, 6 Aug 2019 06:01:12 -0400 Received: by mail-yw1-f67.google.com with SMTP id u141so30625144ywe.4 for ; Tue, 06 Aug 2019 03:01:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=X1kq35amQF0eADWBqq2tRXGYPbvo4jnAQagrNi2mP5k=; b=ryN6Ug8NTpg6DdZSRbeCs9SgNy9VYtFjReXZvH386JZijbFKUzuZ1IjFN+pJi8xLPk LukM2OHMl1jpO+jAcXDzJzG1kaH2PnG+tcT5DoqbCGgCYAsjKehsHtqdpjk7TYaP+3CV HZ1GbOcghRxf92Hbf1SK5LK2/I8WDRR2FVLhSdgtj7ZW3y/uM0N3UDKoHjXcgpIcRbHD 1AYRQOWT3JC1YJ6kRjEADY9+WyGfW67uyh8F5pYDNBg65QJ+un2Ii1vzMKBODmSrobuN Vw2Yd3mHVNb3h8K0DrfYubyUTL2jde6CpXbbokcZVLtq5/WG2hhHq4YewOfhnaY442nK tnBg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=X1kq35amQF0eADWBqq2tRXGYPbvo4jnAQagrNi2mP5k=; b=R93NyosSnt+Q2Vob+wkvcfVR3Jk/x0V88xfkz4agVsRaMOq1YlJ9oEGQOcd3q2/WsZ IB6O+Ja37gsb80/kg4fXORZ0s9ITGeOFHp1KIHpkBofH0aq7V8TZCDoUJ4UXkY4Jxd3o gYd6K26wwM/gwB8VuLCj12jJZklBBkh2Frah09LoyjtVwEX1qDG13CCSXFsEDWyap3kS PwwBda8mjW+clcfrMEDY5Px3V/+WU1/IxZGH1/4UUIznJckMPpxe+nS8AO9AdMzUcx2t 3XDvwulCaV/ckPIpo7fal2T5dk/Lb2zaI6wGQ6LnM3gHVH6T+OYt98uZMqOXNLtQbWDt P8Aw== X-Gm-Message-State: APjAAAVydKWYMqpXczMqY+DOJI7NSRiaFA0cYFpF/1XUsFjJmmfLZMzO +U26HTAqtE8L1hKXJAt++SZ8MA== X-Google-Smtp-Source: APXvYqwIma0HV1pnR7Z1+fYCWlNvk6seDzFUGYoiNt+a7UQALBxCkV/06ohxlMAH3c2ynUJgGkffCA== X-Received: by 2002:a81:2545:: with SMTP id l66mr1596296ywl.489.1565085671977; Tue, 06 Aug 2019 03:01:11 -0700 (PDT) Received: from localhost.localdomain (li1322-146.members.linode.com. [45.79.223.146]) by smtp.gmail.com with ESMTPSA id h12sm18316685ywm.91.2019.08.06.03.01.02 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Tue, 06 Aug 2019 03:01:11 -0700 (PDT) From: Leo Yan To: Russell King , Oleg Nesterov , Catalin Marinas , Will Deacon , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , x86@kernel.org, Arnd Bergmann , Alexei Starovoitov , Daniel Borkmann , Martin KaFai Lau , Song Liu , Yonghong Song , "Naveen N. Rao" , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-arch@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, clang-built-linux@googlegroups.com, Masami Hiramatsu Cc: Leo Yan Subject: [PATCH v2 2/3] arm64: Add support for function error injection Date: Tue, 6 Aug 2019 18:00:14 +0800 Message-Id: <20190806100015.11256-3-leo.yan@linaro.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190806100015.11256-1-leo.yan@linaro.org> References: <20190806100015.11256-1-leo.yan@linaro.org> Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Inspired by the commit 7cd01b08d35f ("powerpc: Add support for function error injection"), this patch supports function error injection for Arm64. This patch mainly support two functions: one is regs_set_return_value() which is used to overwrite the return value; the another function is override_function_with_return() which is to override the probed function returning and jump to its caller. Signed-off-by: Leo Yan --- arch/arm64/Kconfig | 1 + arch/arm64/include/asm/ptrace.h | 5 +++++ arch/arm64/lib/Makefile | 2 ++ arch/arm64/lib/error-inject.c | 18 ++++++++++++++++++ 4 files changed, 26 insertions(+) create mode 100644 arch/arm64/lib/error-inject.c diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 3adcec05b1f6..b15803afb2a0 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -148,6 +148,7 @@ config ARM64 select HAVE_FAST_GUP select HAVE_FTRACE_MCOUNT_RECORD select HAVE_FUNCTION_TRACER + select HAVE_FUNCTION_ERROR_INJECTION select HAVE_FUNCTION_GRAPH_TRACER select HAVE_GCC_PLUGINS select HAVE_HW_BREAKPOINT if PERF_EVENTS diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h index b1dd039023ef..891b9995cb4b 100644 --- a/arch/arm64/include/asm/ptrace.h +++ b/arch/arm64/include/asm/ptrace.h @@ -301,6 +301,11 @@ static inline unsigned long regs_return_value(struct pt_regs *regs) return regs->regs[0]; } +static inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc) +{ + regs->regs[0] = rc; +} + /** * regs_get_kernel_argument() - get Nth function argument in kernel * @regs: pt_regs of that context diff --git a/arch/arm64/lib/Makefile b/arch/arm64/lib/Makefile index 33c2a4abda04..f182ccb0438e 100644 --- a/arch/arm64/lib/Makefile +++ b/arch/arm64/lib/Makefile @@ -33,3 +33,5 @@ UBSAN_SANITIZE_atomic_ll_sc.o := n lib-$(CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE) += uaccess_flushcache.o obj-$(CONFIG_CRC32) += crc32.o + +obj-$(CONFIG_FUNCTION_ERROR_INJECTION) += error-inject.o diff --git a/arch/arm64/lib/error-inject.c b/arch/arm64/lib/error-inject.c new file mode 100644 index 000000000000..ed15021da3ed --- /dev/null +++ b/arch/arm64/lib/error-inject.c @@ -0,0 +1,18 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include + +void override_function_with_return(struct pt_regs *regs) +{ + /* + * 'regs' represents the state on entry of a predefined function in + * the kernel/module and which is captured on a kprobe. + * + * When kprobe returns back from exception it will override the end + * of probed function and directly return to the predefined + * function's caller. + */ + instruction_pointer_set(regs, procedure_link_pointer(regs)); +} +NOKPROBE_SYMBOL(override_function_with_return); -- 2.17.1