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 Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (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 9FE93C4321E for ; Sun, 27 Nov 2022 13:03:35 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4NKpgp20bZz3cND for ; Mon, 28 Nov 2022 00:03:34 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20210112 header.b=DdzJ9fY/; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=gmail.com (client-ip=2607:f8b0:4864:20::52b; helo=mail-pg1-x52b.google.com; envelope-from=npiggin@gmail.com; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20210112 header.b=DdzJ9fY/; dkim-atps=neutral Received: from mail-pg1-x52b.google.com (mail-pg1-x52b.google.com [IPv6:2607:f8b0:4864:20::52b]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4NKpNd3912z3f3Y for ; Sun, 27 Nov 2022 23:50:25 +1100 (AEDT) Received: by mail-pg1-x52b.google.com with SMTP id v3so7648050pgh.4 for ; Sun, 27 Nov 2022 04:50:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=WvIGD2m1L4RbhSq+kD/Yyum0ENbCwI3WlJ1O1AI1zmI=; b=DdzJ9fY/7PUO8jIauYLgb3xiTo09RWLEIQav9s9cHPNSiLCBiRL93LPh70pT/Fo1DX HICnok1FWmJtDZNfoB/AE3CEiOWav3w4bhj1DKeWge6ZpdUhOrpvzoXjMycjhjI5ddyo JTBSbboHSNALVBZ/Jl7QWpjlbPkxdFv1PUSHCrrjw4jb+gjrw+YM9DEeQRynYwhA4RF1 2pGQYv75W3MgNexiwMyElbsK00Y2rvQdIkOk/QaE4lY7M3K6CLu0TcdOPvX0HKxnEVg3 qDZ+jJZQxOryx8pDm1YuKL97nLTvAcg5u24QbDtL/uzLxPhad80B9KmWjr39d3UGV00M llmg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=WvIGD2m1L4RbhSq+kD/Yyum0ENbCwI3WlJ1O1AI1zmI=; b=yFsUkqJErmKmdeBoaEvvZ8HSndW10DEDHzdOlPcxJQ9+XxKzPIvIJS0FjMdcn/OR2M VoSAjTSza+8B12X0Pxc480HdoF6STyWMcgcDLio9+asLz98f6jpzUc34JZGlzvxUAHd6 ru2w3q3WY0lPUwXUNCAF3XEggn7TsHELj4r0oCp7PFor4K7O1ckAkSXqaCyzarMoPSqp Ok7m27BRbQb6rCJdsI2GO3D3YHxqDOmb6m7BITuzVsx1ox6BvSgnUQNNAnAYFHcOzFEl Jyrxo8qYQcx7C/MctlhGDClYLV2Q8PzpNQYpsj8b3Idsn3CWOl0hKnwc3dKY1BN83xfy f2mA== X-Gm-Message-State: ANoB5plkfso7/y2S5XUiQxV/vXo9sBu3EKi3qZMMs+iLb9tAYGEAhx2o +3+RSRckI+EWq94yZm1FLzG4uSoiL1lSfw== X-Google-Smtp-Source: AA0mqf7czBiysUYNBBX4KR2fzrEJ5tyaAlKj07HNEiFWL069GyqZyIOC1nb92qdxdbBkm1zKpEMjuQ== X-Received: by 2002:a63:4043:0:b0:470:2ecd:333e with SMTP id n64-20020a634043000000b004702ecd333emr42124147pga.596.1669553422629; Sun, 27 Nov 2022 04:50:22 -0800 (PST) Received: from bobo.ozlabs.ibm.com ([220.240.231.60]) by smtp.gmail.com with ESMTPSA id q13-20020a63e20d000000b00473c36ea150sm5102287pgh.92.2022.11.27.04.50.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 27 Nov 2022 04:50:22 -0800 (PST) From: Nicholas Piggin To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH 14/17] powerpc: split validate_sp into two functions Date: Sun, 27 Nov 2022 22:49:39 +1000 Message-Id: <20221127124942.1665522-15-npiggin@gmail.com> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20221127124942.1665522-1-npiggin@gmail.com> References: <20221127124942.1665522-1-npiggin@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Nicholas Piggin Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Most callers just want to validate an arbitrary kernel stack pointer, some need a particular size. Make the size case the exceptional one with an extra function. Signed-off-by: Nicholas Piggin --- arch/powerpc/include/asm/processor.h | 15 ++++++++++++--- arch/powerpc/kernel/process.c | 23 ++++++++++++++--------- arch/powerpc/kernel/stacktrace.c | 2 +- arch/powerpc/perf/callchain.c | 6 +++--- 4 files changed, 30 insertions(+), 16 deletions(-) diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h index 631802999d59..e96c9b8c2a60 100644 --- a/arch/powerpc/include/asm/processor.h +++ b/arch/powerpc/include/asm/processor.h @@ -374,9 +374,18 @@ static inline unsigned long __pack_fe01(unsigned int fpmode) #endif -/* Check that a certain kernel stack pointer is valid in task_struct p */ -int validate_sp(unsigned long sp, struct task_struct *p, - unsigned long nbytes); +/* + * Check that a certain kernel stack pointer is a valid (minimum sized) + * stack frame in task_struct p. + */ +int validate_sp(unsigned long sp, struct task_struct *p); + +/* + * validate the stack frame of a particular minimum size, used for when we are + * looking at a certain object in the stack beyond the minimum. + */ +int validate_sp_size(unsigned long sp, struct task_struct *p, + unsigned long nbytes); /* * Prefetch macros. diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index 6cb3982a11ef..6820d90744c3 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -2128,9 +2128,12 @@ static inline int valid_emergency_stack(unsigned long sp, struct task_struct *p, return 0; } - -int validate_sp(unsigned long sp, struct task_struct *p, - unsigned long nbytes) +/* + * validate the stack frame of a particular minimum size, used for when we are + * looking at a certain object in the stack beyond the minimum. + */ +int validate_sp_size(unsigned long sp, struct task_struct *p, + unsigned long nbytes) { unsigned long stack_page = (unsigned long)task_stack_page(p); @@ -2146,7 +2149,10 @@ int validate_sp(unsigned long sp, struct task_struct *p, return valid_emergency_stack(sp, p, nbytes); } -EXPORT_SYMBOL(validate_sp); +int validate_sp(unsigned long sp, struct task_struct *p) +{ + return validate_sp_size(sp, p, STACK_FRAME_OVERHEAD); +} static unsigned long ___get_wchan(struct task_struct *p) { @@ -2154,13 +2160,12 @@ static unsigned long ___get_wchan(struct task_struct *p) int count = 0; sp = p->thread.ksp; - if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD)) + if (!validate_sp(sp, p)) return 0; do { sp = READ_ONCE_NOCHECK(*(unsigned long *)sp); - if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD) || - task_is_running(p)) + if (!validate_sp(sp, p) || task_is_running(p)) return 0; if (count > 0) { ip = READ_ONCE_NOCHECK(((unsigned long *)sp)[STACK_FRAME_LR_SAVE]); @@ -2214,7 +2219,7 @@ void __no_sanitize_address show_stack(struct task_struct *tsk, lr = 0; printk("%sCall Trace:\n", loglvl); do { - if (!validate_sp(sp, tsk, STACK_FRAME_OVERHEAD)) + if (!validate_sp(sp, tsk)) break; stack = (unsigned long *) sp; @@ -2241,7 +2246,7 @@ void __no_sanitize_address show_stack(struct task_struct *tsk, * could hold a pt_regs, if that does not fit then it can't * have regs. */ - if (validate_sp(sp, tsk, STACK_SWITCH_FRAME_SIZE) + if (validate_sp_size(sp, tsk, STACK_SWITCH_FRAME_SIZE) && stack[STACK_INT_FRAME_MARKER_LONGS] == STACK_FRAME_REGS_MARKER) { struct pt_regs *regs = (struct pt_regs *) (sp + STACK_INT_FRAME_REGS); diff --git a/arch/powerpc/kernel/stacktrace.c b/arch/powerpc/kernel/stacktrace.c index 453ac317a6cf..1dbbf30f265e 100644 --- a/arch/powerpc/kernel/stacktrace.c +++ b/arch/powerpc/kernel/stacktrace.c @@ -43,7 +43,7 @@ void __no_sanitize_address arch_stack_walk(stack_trace_consume_fn consume_entry, unsigned long *stack = (unsigned long *) sp; unsigned long newsp, ip; - if (!validate_sp(sp, task, STACK_FRAME_OVERHEAD)) + if (!validate_sp(sp, task)) return; newsp = stack[0]; diff --git a/arch/powerpc/perf/callchain.c b/arch/powerpc/perf/callchain.c index b01497ed5173..6b4434dd0ff3 100644 --- a/arch/powerpc/perf/callchain.c +++ b/arch/powerpc/perf/callchain.c @@ -27,7 +27,7 @@ static int valid_next_sp(unsigned long sp, unsigned long prev_sp) { if (sp & 0xf) return 0; /* must be 16-byte aligned */ - if (!validate_sp(sp, current, STACK_FRAME_OVERHEAD)) + if (!validate_sp(sp, current)) return 0; if (sp >= prev_sp + STACK_FRAME_MIN_SIZE) return 1; @@ -53,7 +53,7 @@ perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *re sp = regs->gpr[1]; perf_callchain_store(entry, perf_instruction_pointer(regs)); - if (!validate_sp(sp, current, STACK_FRAME_OVERHEAD)) + if (!validate_sp(sp, current)) return; for (;;) { @@ -61,7 +61,7 @@ perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *re next_sp = fp[0]; if (next_sp == sp + STACK_INT_FRAME_SIZE && - validate_sp(sp, current, STACK_INT_FRAME_SIZE) && + validate_sp_size(sp, current, STACK_INT_FRAME_SIZE) && fp[STACK_INT_FRAME_MARKER_LONGS] == STACK_FRAME_REGS_MARKER) { /* * This looks like an interrupt frame for an -- 2.37.2