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=-9.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 83E28C43331 for ; Fri, 27 Mar 2020 15:29:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 44ADE20578 for ; Fri, 27 Mar 2020 15:29:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="QC1S8I24" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727943AbgC0P32 (ORCPT ); Fri, 27 Mar 2020 11:29:28 -0400 Received: from us-smtp-delivery-74.mimecast.com ([63.128.21.74]:35690 "EHLO us-smtp-delivery-74.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727927AbgC0P3Z (ORCPT ); Fri, 27 Mar 2020 11:29:25 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1585322964; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/mEWeSwhR59yw9Ak8V6RZalo/Kp7qjssrQ2/0RA8kQE=; b=QC1S8I241sdGfzeKmnZ6htJBiNLZbdZbAqtFfLW0OqxOsvzGuazwylp0xhk7SvbKFgSmW6 hJc5C6xq4+LmRrxB+vE6d/eyUiGXmwVzUg89IO31RzX7uNmxY0JyHQxq8NZUaZgjkavNOe Ef9hc8XHDrdDp5Ll4tqFTREDIcHNLGY= Received: from mail-wr1-f71.google.com (mail-wr1-f71.google.com [209.85.221.71]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-286-Ct5hiuliP1qeOEhDg4yNag-1; Fri, 27 Mar 2020 11:29:23 -0400 X-MC-Unique: Ct5hiuliP1qeOEhDg4yNag-1 Received: by mail-wr1-f71.google.com with SMTP id y1so3589454wrp.5 for ; Fri, 27 Mar 2020 08:29:23 -0700 (PDT) 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:mime-version:content-transfer-encoding; bh=/mEWeSwhR59yw9Ak8V6RZalo/Kp7qjssrQ2/0RA8kQE=; b=X4CBsqqQYyugVOdiOxo44mY/MReXo8T2ra/Y2ZuaV+qnKSj3iAboIOcuQKKdg6N7fR o2Yokh6YvBaUyYJ9hzcDyUBMqnoT7JJpShjGyu9r9dT4WWaxtgOeSWHs9qxvYBUrgr2T yVUAv9Cdf62/H/PtaAJwxmF7s0PtSTyBG1RCgVcFvcGtoXzizncy9NweppRc4YGit5WT 3Fr8z1NvUQYY5Jsmjx5rm6m7r2BZwGyHxpXFlsuBwsAhdeVyu0vJ8VrPLpu82apBKIDI OMlWTTHRCRJZ/8k0QmAy7O+bdOtfLCoD6eFWYFFA75qtRcaDFBt0JFCqSXQ36hIevJV7 Aj1Q== X-Gm-Message-State: ANhLgQ0QpHY/7i296PK2fKV+iezwDKKzvLIKcvE3p2UFes8QysqKukif HS0GxZSOWVQT8Y8Ah+2k8PXvCqB78LVred0cnJyWJXVyNd/ljejES9dilC4saiv55gvoSYtKx2Y yu+Pb0a6s9ZNg3NtGj8V6sLCb X-Received: by 2002:adf:d088:: with SMTP id y8mr3526wrh.36.1585322961216; Fri, 27 Mar 2020 08:29:21 -0700 (PDT) X-Google-Smtp-Source: ADFU+vso9T96ctq68Z51Be1Hkx9c5NUtkarkImGuuD/l3NTlLR68LjZPrcYtr7unEOZvzpXGXwu3FA== X-Received: by 2002:adf:d088:: with SMTP id y8mr3497wrh.36.1585322960915; Fri, 27 Mar 2020 08:29:20 -0700 (PDT) Received: from redfedo.redhat.com ([2a01:cb14:58d:8400:ecf6:58e2:9c06:a308]) by smtp.gmail.com with ESMTPSA id i8sm8906856wrb.41.2020.03.27.08.29.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 27 Mar 2020 08:29:18 -0700 (PDT) From: Julien Thierry To: linux-kernel@vger.kernel.org Cc: jpoimboe@redhat.com, peterz@infradead.org, raphael.gault@arm.com, Julien Thierry Subject: [PATCH v2 10/10] objtool: Support multiple stack_op per instruction Date: Fri, 27 Mar 2020 15:28:47 +0000 Message-Id: <20200327152847.15294-11-jthierry@redhat.com> X-Mailer: git-send-email 2.21.1 In-Reply-To: <20200327152847.15294-1-jthierry@redhat.com> References: <20200327152847.15294-1-jthierry@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Instruction sets can include more or less complex operations which might not fit the currently defined set of stack_ops. Combining more than one stack_op provides more flexibility to describe the behaviour of an instruction. This also reduces the need to define new stack_ops specific to a single instruction set. Allow instruction decoders to generate multiple stack_op per instruction. Signed-off-by: Julien Thierry --- tools/objtool/arch.h | 4 +- tools/objtool/arch/x86/decode.c | 13 +++++- tools/objtool/check.c | 74 ++++++++++++++++++++------------- tools/objtool/check.h | 2 +- 4 files changed, 62 insertions(+), 31 deletions(-) diff --git a/tools/objtool/arch.h b/tools/objtool/arch.h index a9a50a25ca66..f9883c431949 100644 --- a/tools/objtool/arch.h +++ b/tools/objtool/arch.h @@ -64,6 +64,7 @@ struct op_src { struct stack_op { struct op_dest dest; struct op_src src; + struct list_head list; }; struct instruction; @@ -73,7 +74,8 @@ void arch_initial_func_cfi_state(struct cfi_state *state); int arch_decode_instruction(struct elf *elf, struct section *sec, unsigned long offset, unsigned int maxlen, unsigned int *len, enum insn_type *type, - unsigned long *immediate, struct stack_op *op); + unsigned long *immediate, + struct list_head *ops_list); bool arch_callee_saved_reg(unsigned char reg); diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c index 7ce8650cf085..199b4084a13c 100644 --- a/tools/objtool/arch/x86/decode.c +++ b/tools/objtool/arch/x86/decode.c @@ -80,13 +80,15 @@ unsigned long arch_jump_destination(struct instruction *insn) int arch_decode_instruction(struct elf *elf, struct section *sec, unsigned long offset, unsigned int maxlen, unsigned int *len, enum insn_type *type, - unsigned long *immediate, struct stack_op *op) + unsigned long *immediate, + struct list_head *ops_list) { struct insn insn; int x86_64, sign; unsigned char op1, op2, rex = 0, rex_b = 0, rex_r = 0, rex_w = 0, rex_x = 0, modrm = 0, modrm_mod = 0, modrm_rm = 0, modrm_reg = 0, sib = 0; + struct stack_op *op; x86_64 = is_x86_64(elf); if (x86_64 == -1) @@ -127,6 +129,10 @@ int arch_decode_instruction(struct elf *elf, struct section *sec, if (insn.sib.nbytes) sib = insn.sib.bytes[0]; + op = calloc(1, sizeof(*op)); + if (!op) + return -1; + switch (op1) { case 0x1: @@ -488,6 +494,11 @@ int arch_decode_instruction(struct elf *elf, struct section *sec, *immediate = insn.immediate.nbytes ? insn.immediate.value : 0; + if (*type == INSN_STACK) + list_add_tail(&op->list, ops_list); + else + free(op); + return 0; } diff --git a/tools/objtool/check.c b/tools/objtool/check.c index dbfd1f5d06f7..30d916dcc2a8 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -260,6 +260,7 @@ static int decode_instructions(struct objtool_file *file) } memset(insn, 0, sizeof(*insn)); INIT_LIST_HEAD(&insn->alts); + INIT_LIST_HEAD(&insn->stack_ops); clear_insn_state(&insn->state); insn->sec = sec; @@ -269,7 +270,7 @@ static int decode_instructions(struct objtool_file *file) sec->len - offset, &insn->len, &insn->type, &insn->immediate, - &insn->stack_op); + &insn->stack_ops); if (ret) goto err; @@ -757,6 +758,7 @@ static int handle_group_alt(struct objtool_file *file, } memset(fake_jump, 0, sizeof(*fake_jump)); INIT_LIST_HEAD(&fake_jump->alts); + INIT_LIST_HEAD(&fake_jump->stack_ops); clear_insn_state(&fake_jump->state); fake_jump->sec = special_alt->new_sec; @@ -1459,10 +1461,11 @@ static bool has_valid_stack_frame(struct insn_state *state) return false; } -static int update_insn_state_regs(struct instruction *insn, struct insn_state *state) +static int update_insn_state_regs(struct instruction *insn, + struct insn_state *state, + struct stack_op *op) { struct cfi_reg *cfa = &state->cfa; - struct stack_op *op = &insn->stack_op; if (cfa->base != CFI_SP) return 0; @@ -1552,9 +1555,9 @@ static void restore_reg(struct insn_state *state, unsigned char reg) * 41 5d pop %r13 * c3 retq */ -static int update_insn_state(struct instruction *insn, struct insn_state *state) +static int update_insn_state(struct instruction *insn, struct insn_state *state, + struct stack_op *op) { - struct stack_op *op = &insn->stack_op; struct cfi_reg *cfa = &state->cfa; struct cfi_reg *regs = state->regs; @@ -1568,7 +1571,7 @@ static int update_insn_state(struct instruction *insn, struct insn_state *state) } if (state->type == ORC_TYPE_REGS || state->type == ORC_TYPE_REGS_IRET) - return update_insn_state_regs(insn, state); + return update_insn_state_regs(insn, state, op); switch (op->dest.type) { @@ -1905,6 +1908,42 @@ static int update_insn_state(struct instruction *insn, struct insn_state *state) return 0; } +static int handle_insn_ops(struct instruction *insn, struct insn_state *state) +{ + struct stack_op *op; + + list_for_each_entry(op, &insn->stack_ops, list) { + int res; + + res = update_insn_state(insn, state, op); + if (res) + return res; + + if (op->dest.type == OP_DEST_PUSHF) { + if (!state->uaccess_stack) { + state->uaccess_stack = 1; + } else if (state->uaccess_stack >> 31) { + WARN_FUNC("PUSHF stack exhausted", + insn->sec, insn->offset); + return 1; + } + state->uaccess_stack <<= 1; + state->uaccess_stack |= state->uaccess; + } + + if (op->src.type == OP_SRC_POPF) { + if (state->uaccess_stack) { + state->uaccess = state->uaccess_stack & 1; + state->uaccess_stack >>= 1; + if (state->uaccess_stack == 1) + state->uaccess_stack = 0; + } + } + } + + return 0; +} + static bool insn_state_match(struct instruction *insn, struct insn_state *state) { struct insn_state *state1 = &insn->state, *state2 = state; @@ -2205,29 +2244,8 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, return 0; case INSN_STACK: - if (update_insn_state(insn, &state)) + if (handle_insn_ops(insn, &state)) return 1; - - if (insn->stack_op.dest.type == OP_DEST_PUSHF) { - if (!state.uaccess_stack) { - state.uaccess_stack = 1; - } else if (state.uaccess_stack >> 31) { - WARN_FUNC("PUSHF stack exhausted", sec, insn->offset); - return 1; - } - state.uaccess_stack <<= 1; - state.uaccess_stack |= state.uaccess; - } - - if (insn->stack_op.src.type == OP_SRC_POPF) { - if (state.uaccess_stack) { - state.uaccess = state.uaccess_stack & 1; - state.uaccess_stack >>= 1; - if (state.uaccess_stack == 1) - state.uaccess_stack = 0; - } - } - break; case INSN_STAC: diff --git a/tools/objtool/check.h b/tools/objtool/check.h index d1b55961474c..1a089fc0bd23 100644 --- a/tools/objtool/check.h +++ b/tools/objtool/check.h @@ -43,7 +43,7 @@ struct instruction { struct list_head alts; struct symbol *func; struct symbol *code_sym; - struct stack_op stack_op; + struct list_head stack_ops; struct insn_state state; struct orc_entry orc; }; -- 2.21.1