From patchwork Sun May 5 16:06:27 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Rapoport X-Patchwork-Id: 13654587 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 7516FC04FFE for ; Sun, 5 May 2024 17:15:40 +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:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=L5TSMxcWfXn2V8m/GcJMT0oj/KDTOQuWzNXEnPZE33o=; b=Hlq+ItJ3ofaD4k GX0zlCFLUE4IKUe4/x28eEaL6ETMxztAP61BRR757mHJ4igABt4qhBiNzdMMC3P3kfbjW2PJgUR9o 1bAtc6EFf9SkmtzYxPCVL1E/XXG2cxj40co5h6CbQo22hmACZuDhetMZFHwhl0cDY0a7L9LoAuq+m oWWXSLABmOzqm2iyKqY7oiBChmpCcNOYFqE/L5v52snH2w40PM0H4tAhK+IWQv/sqO5UVMQIPBmD0 fx5LawrQ1WTiHzwvKK4iqUC3CvBz6aY1OdYD6E8Vo+SjDhUHdGsLFvwKYGxttZl7S2gJFuU1sW0x/ XHgNersiafPAsd0vkc5A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1s3fSS-00000004tkh-3cCF; Sun, 05 May 2024 17:15:28 +0000 Received: from sin.source.kernel.org ([145.40.73.55]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1s3eQu-00000004j7A-2ssc; Sun, 05 May 2024 16:10:03 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id 5E337CE0AB6; Sun, 5 May 2024 16:09:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5EA5FC113CC; Sun, 5 May 2024 16:09:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1714925385; bh=n6mgI0H/39mvE4gYkoCj3q2CT30/D9BQcnyPUkYmzdE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QCCxshquMQZIYmLR9BC2goOIG2WvDcQZSg4DMYmv4seH5u50FAyr5sSSu2cZTrq1k 1aq+DM7MtvC7uYy0L8lK7PUeKUGNcYzI26AhgX3k+r02BvoRIp85vYxuQwIqVSaqj2 hLeSFjrZkntdHxjj1YiwU+8/c+M2CdO9FTQ83Tem8TFxYi+7kYUCfmvU8yl0uDpd2x m78cxpLmGVeNZ571v7raPKrnKA0wMo/A7REebj23qa4T/Fhgzr+SGtEZsj8TQEZkpT W1OzDnAhQ8QtznLGNpOdi4R9Un20Sv+DQV1jy2eugEuIIQ+7oEtAwZhBh0k+TDvo2C r8YK/n2WwOQHw== From: Mike Rapoport To: linux-kernel@vger.kernel.org Cc: Alexandre Ghiti , Andrew Morton , =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= , Catalin Marinas , Christophe Leroy , "David S. Miller" , Dinh Nguyen , Donald Dutile , Eric Chanudet , Heiko Carstens , Helge Deller , Huacai Chen , Kent Overstreet , Liviu Dudau , Luis Chamberlain , Mark Rutland , Masami Hiramatsu , Michael Ellerman , Mike Rapoport , Nadav Amit , Palmer Dabbelt , Peter Zijlstra , =?utf-8?q?Philippe_Mathieu-Daud?= =?utf-8?q?=C3=A9?= , Rick Edgecombe , Russell King , Sam Ravnborg , Song Liu , Steven Rostedt , Thomas Bogendoerfer , Thomas Gleixner , Will Deacon , bpf@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mips@vger.kernel.org, linux-mm@kvack.org, linux-modules@vger.kernel.org, linux-parisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, loongarch@lists.linux.dev, netdev@vger.kernel.org, sparclinux@vger.kernel.org, x86@kernel.org Subject: [PATCH RESEND v8 15/16] kprobes: remove dependency on CONFIG_MODULES Date: Sun, 5 May 2024 19:06:27 +0300 Message-ID: <20240505160628.2323363-16-rppt@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240505160628.2323363-1-rppt@kernel.org> References: <20240505160628.2323363-1-rppt@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240505_090949_324595_9DC38C08 X-CRM114-Status: GOOD ( 21.37 ) X-BeenThere: linux-arm-kernel@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-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: "Mike Rapoport (IBM)" kprobes depended on CONFIG_MODULES because it has to allocate memory for code. Since code allocations are now implemented with execmem, kprobes can be enabled in non-modular kernels. Add #ifdef CONFIG_MODULE guards for the code dealing with kprobes inside modules, make CONFIG_KPROBES select CONFIG_EXECMEM and drop the dependency of CONFIG_KPROBES on CONFIG_MODULES. Signed-off-by: Mike Rapoport (IBM) Acked-by: Masami Hiramatsu (Google) --- arch/Kconfig | 2 +- include/linux/module.h | 9 ++++++ kernel/kprobes.c | 55 +++++++++++++++++++++++-------------- kernel/trace/trace_kprobe.c | 20 +++++++++++++- 4 files changed, 63 insertions(+), 23 deletions(-) diff --git a/arch/Kconfig b/arch/Kconfig index 4fd0daa54e6c..caa459964f09 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -52,9 +52,9 @@ config GENERIC_ENTRY config KPROBES bool "Kprobes" - depends on MODULES depends on HAVE_KPROBES select KALLSYMS + select EXECMEM select TASKS_RCU if PREEMPTION help Kprobes allows you to trap at almost any kernel address and diff --git a/include/linux/module.h b/include/linux/module.h index 1153b0d99a80..ffa1c603163c 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -605,6 +605,11 @@ static inline bool module_is_live(struct module *mod) return mod->state != MODULE_STATE_GOING; } +static inline bool module_is_coming(struct module *mod) +{ + return mod->state == MODULE_STATE_COMING; +} + struct module *__module_text_address(unsigned long addr); struct module *__module_address(unsigned long addr); bool is_module_address(unsigned long addr); @@ -857,6 +862,10 @@ void *dereference_module_function_descriptor(struct module *mod, void *ptr) return ptr; } +static inline bool module_is_coming(struct module *mod) +{ + return false; +} #endif /* CONFIG_MODULES */ #ifdef CONFIG_SYSFS diff --git a/kernel/kprobes.c b/kernel/kprobes.c index ddd7cdc16edf..ca2c6cbd42d2 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1588,7 +1588,7 @@ static int check_kprobe_address_safe(struct kprobe *p, } /* Get module refcount and reject __init functions for loaded modules. */ - if (*probed_mod) { + if (IS_ENABLED(CONFIG_MODULES) && *probed_mod) { /* * We must hold a refcount of the probed module while updating * its code to prohibit unexpected unloading. @@ -1603,12 +1603,13 @@ static int check_kprobe_address_safe(struct kprobe *p, * kprobes in there. */ if (within_module_init((unsigned long)p->addr, *probed_mod) && - (*probed_mod)->state != MODULE_STATE_COMING) { + !module_is_coming(*probed_mod)) { module_put(*probed_mod); *probed_mod = NULL; ret = -ENOENT; } } + out: preempt_enable(); jump_label_unlock(); @@ -2488,24 +2489,6 @@ int kprobe_add_area_blacklist(unsigned long start, unsigned long end) return 0; } -/* Remove all symbols in given area from kprobe blacklist */ -static void kprobe_remove_area_blacklist(unsigned long start, unsigned long end) -{ - struct kprobe_blacklist_entry *ent, *n; - - list_for_each_entry_safe(ent, n, &kprobe_blacklist, list) { - if (ent->start_addr < start || ent->start_addr >= end) - continue; - list_del(&ent->list); - kfree(ent); - } -} - -static void kprobe_remove_ksym_blacklist(unsigned long entry) -{ - kprobe_remove_area_blacklist(entry, entry + 1); -} - int __weak arch_kprobe_get_kallsym(unsigned int *symnum, unsigned long *value, char *type, char *sym) { @@ -2570,6 +2553,25 @@ static int __init populate_kprobe_blacklist(unsigned long *start, return ret ? : arch_populate_kprobe_blacklist(); } +#ifdef CONFIG_MODULES +/* Remove all symbols in given area from kprobe blacklist */ +static void kprobe_remove_area_blacklist(unsigned long start, unsigned long end) +{ + struct kprobe_blacklist_entry *ent, *n; + + list_for_each_entry_safe(ent, n, &kprobe_blacklist, list) { + if (ent->start_addr < start || ent->start_addr >= end) + continue; + list_del(&ent->list); + kfree(ent); + } +} + +static void kprobe_remove_ksym_blacklist(unsigned long entry) +{ + kprobe_remove_area_blacklist(entry, entry + 1); +} + static void add_module_kprobe_blacklist(struct module *mod) { unsigned long start, end; @@ -2672,6 +2674,17 @@ static struct notifier_block kprobe_module_nb = { .priority = 0 }; +static int kprobe_register_module_notifier(void) +{ + return register_module_notifier(&kprobe_module_nb); +} +#else +static int kprobe_register_module_notifier(void) +{ + return 0; +} +#endif /* CONFIG_MODULES */ + void kprobe_free_init_mem(void) { void *start = (void *)(&__init_begin); @@ -2731,7 +2744,7 @@ static int __init init_kprobes(void) if (!err) err = register_die_notifier(&kprobe_exceptions_nb); if (!err) - err = register_module_notifier(&kprobe_module_nb); + err = kprobe_register_module_notifier(); kprobes_initialized = (err == 0); kprobe_sysctls_init(); diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 14099cc17fc9..2cb2a3951b4f 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -111,6 +111,7 @@ static nokprobe_inline bool trace_kprobe_within_module(struct trace_kprobe *tk, return strncmp(module_name(mod), name, len) == 0 && name[len] == ':'; } +#ifdef CONFIG_MODULES static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk) { char *p; @@ -129,6 +130,12 @@ static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk) return ret; } +#else +static inline bool trace_kprobe_module_exist(struct trace_kprobe *tk) +{ + return false; +} +#endif static bool trace_kprobe_is_busy(struct dyn_event *ev) { @@ -670,6 +677,7 @@ static int register_trace_kprobe(struct trace_kprobe *tk) return ret; } +#ifdef CONFIG_MODULES /* Module notifier call back, checking event on the module */ static int trace_kprobe_module_callback(struct notifier_block *nb, unsigned long val, void *data) @@ -704,6 +712,16 @@ static struct notifier_block trace_kprobe_module_nb = { .notifier_call = trace_kprobe_module_callback, .priority = 1 /* Invoked after kprobe module callback */ }; +static int trace_kprobe_register_module_notifier(void) +{ + return register_module_notifier(&trace_kprobe_module_nb); +} +#else +static int trace_kprobe_register_module_notifier(void) +{ + return 0; +} +#endif /* CONFIG_MODULES */ static int count_symbols(void *data, unsigned long unused) { @@ -1933,7 +1951,7 @@ static __init int init_kprobe_trace_early(void) if (ret) return ret; - if (register_module_notifier(&trace_kprobe_module_nb)) + if (trace_kprobe_register_module_notifier()) return -EINVAL; return 0;