From patchwork Wed Mar 6 20:05:10 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Calvin Owens X-Patchwork-Id: 13584596 Received: from mail-pl1-f181.google.com (mail-pl1-f181.google.com [209.85.214.181]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5C19214373E; Wed, 6 Mar 2024 20:05:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.181 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709755552; cv=none; b=rNNdJgwaXZun7LqJeET6tPNBWjeCMzIz6XhaP5DkYwGDb9BulxgtPROrwrPYa1BJ3zViFoO5vPRb91CKhPQJWlWy+kjbJ137nqp/cG9EeoynJ+QbPfIzMyrtFQyib/NH9GAzqkvMzkJEOJkMNIYQs57hBm38JrakQF2MA7xW6Ds= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709755552; c=relaxed/simple; bh=plb56a5rhyamjhuFzBgg3vJIKSYIbdnXKncSM6kqvIY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=YSy6lM3l4AVYu5a4H0adjab5YKor7TWyl9hcOMfzyCp3u0cPIoDUrZ/cSAY94do0t3q6o3fZInAwAFnLphOTRkw1EyatNEDf6nWzlokWlo+Z9+ivKWqMoLrC0xAR6PhmGmwoaBeYcJyX5ZXOkhXEO7lcY9vQxpITusVR/cm9VRI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=eu1a2O/q; arc=none smtp.client-ip=209.85.214.181 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="eu1a2O/q" Received: by mail-pl1-f181.google.com with SMTP id d9443c01a7336-1dd2dca2007so932025ad.2; Wed, 06 Mar 2024 12:05:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1709755550; x=1710360350; darn=vger.kernel.org; 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=xXTKoLXqIrz4+7SOUgtyLjrSNsVHgUbwLacVV55lgdc=; b=eu1a2O/q0bN7//Bbb14Qr4gXMAIvb709kIX4hrk76lgNDhVX0HQNYzi5HByDk4ponA 2nj7FpTtjDJQrNYHxxmbN3dacBL6hKSuEES7tivholWkCXaEkJ39w+2CpHo6D1UcE/+r XaY8z3rhOgze1qUsDKKwU1wIRB1N6TrYZzounKKkg67hDqi2Ps/Ql5JOKBwZK3SGVzOI e3r84r/08YA/Fm7SXAhXI0xStJ0EvvETbEv/2e8Bma75QPTEPvCOW3YtLFjDrCjnZA/1 +vP0EBvaXHP6JLMwaGKYi5YfwuwB7DqJJ+UrnrgXYWznVuU/4VP+NHPl9d58DjWH/mdk roHQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1709755550; x=1710360350; 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=xXTKoLXqIrz4+7SOUgtyLjrSNsVHgUbwLacVV55lgdc=; b=s6HtjbRNHY6TeefpJGxwpvlxbi/fVGHQAHoLmm0yxHWmRQVv4FHiRVzwmzN4FTTLJS nypt1Q09HyMFbuxgT2qNQM62Q9nhhWYcpzz313QsivQldEuucBRPzIa+BPwQLGXysJ9a AvWzYApNRR/iUzTZ4cXOtW6nM24oL1lfTgSYuxhTTQHcAkLmiZdHlfcwq4rjh6FOpOvE SR/ESaTz117q/4Z2400Ipc8z4O8hvh0XF7s6vgrpilxJDLxcAPnOMABgRDec5/crpRvd mZhxbs+ReP6LFuzrI77q2VEIUTxl7QNi6s1tczVvmpdogp8urpkmW7ZIN/QT9gAi5A7u 4hEw== X-Forwarded-Encrypted: i=1; AJvYcCXpNA8Ie2DQmI2i3kHzk4uS0RHvHTTmKTzOgLc7Reeu//RHI9upkZk1gLix8rM2ba6ynEDdB6d3hB3/MqTja70uTpa5lhs+kmxDB/1eT9VO+sLsE5b1Mu4M5wdK1voS115cs1IwmgMA7eM9je7xtdu+FtqEvmDnzeLc/JtJekE0ug== X-Gm-Message-State: AOJu0Yzq5qt/szKJcaW/3w0HU8xsp4fBQcYAY4Ai6cTbj2rzzLlrV/Do 7oTxurxjEMV/bdLJmyAWTsH2d9tmwMS3+ozn3cGJB4IPbivf3pOL X-Google-Smtp-Source: AGHT+IEiJ2roCAI40K2a3VrS8d+2SDADw8E/cXlaEZMQDwqlxjJ7wW9UFJ/Gb5WylySCIDRIqvZdnA== X-Received: by 2002:a17:903:22c6:b0:1dc:fadb:4b1a with SMTP id y6-20020a17090322c600b001dcfadb4b1amr6868463plg.54.1709755549717; Wed, 06 Mar 2024 12:05:49 -0800 (PST) Received: from mozart.vkv.me ([192.184.166.229]) by smtp.gmail.com with ESMTPSA id n15-20020a170902e54f00b001dcfc88ccf6sm8869341plf.263.2024.03.06.12.05.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 06 Mar 2024 12:05:49 -0800 (PST) From: Calvin Owens To: Luis Chamberlain , Andrew Morton , Alexei Starovoitov , Steven Rostedt , Daniel Borkmann , Andrii Nakryiko , Masami Hiramatsu , Naveen N Rao , Anil S Keshavamurthy , David S Miller , Thomas Gleixner Cc: Calvin Owens , bpf@vger.kernel.org, linux-modules@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RFC][PATCH 3/4] kprobes: Allow kprobes with CONFIG_MODULES=n Date: Wed, 6 Mar 2024 12:05:10 -0800 Message-ID: <2af01251ca21d79fa29092505d192f1f1b746cff.1709676663.git.jcalvinowens@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: References: Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-State: RFC If something like this is merged down the road, it can go in at leisure once the module_alloc change is in: it's a one-way dependency. Signed-off-by: Calvin Owens --- arch/Kconfig | 2 +- kernel/kprobes.c | 22 ++++++++++++++++++++++ kernel/trace/trace_kprobe.c | 11 +++++++++++ 3 files changed, 34 insertions(+), 1 deletion(-) diff --git a/arch/Kconfig b/arch/Kconfig index cfc24ced16dd..e60ce984d095 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -52,8 +52,8 @@ config GENERIC_ENTRY config KPROBES bool "Kprobes" - depends on MODULES depends on HAVE_KPROBES + select MODULE_ALLOC select KALLSYMS select TASKS_RCU if PREEMPTION help diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 9d9095e81792..194270e17d57 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1556,8 +1556,12 @@ static bool is_cfi_preamble_symbol(unsigned long addr) str_has_prefix("__pfx_", symbuf); } +#if IS_ENABLED(CONFIG_MODULES) static int check_kprobe_address_safe(struct kprobe *p, struct module **probed_mod) +#else +static int check_kprobe_address_safe(struct kprobe *p) +#endif { int ret; @@ -1580,6 +1584,7 @@ static int check_kprobe_address_safe(struct kprobe *p, goto out; } +#if IS_ENABLED(CONFIG_MODULES) /* Check if 'p' is probing a module. */ *probed_mod = __module_text_address((unsigned long) p->addr); if (*probed_mod) { @@ -1603,6 +1608,8 @@ static int check_kprobe_address_safe(struct kprobe *p, ret = -ENOENT; } } +#endif + out: preempt_enable(); jump_label_unlock(); @@ -1614,7 +1621,9 @@ int register_kprobe(struct kprobe *p) { int ret; struct kprobe *old_p; +#if IS_ENABLED(CONFIG_MODULES) struct module *probed_mod; +#endif kprobe_opcode_t *addr; bool on_func_entry; @@ -1633,7 +1642,11 @@ int register_kprobe(struct kprobe *p) p->nmissed = 0; INIT_LIST_HEAD(&p->list); +#if IS_ENABLED(CONFIG_MODULES) ret = check_kprobe_address_safe(p, &probed_mod); +#else + ret = check_kprobe_address_safe(p); +#endif if (ret) return ret; @@ -1676,8 +1689,10 @@ int register_kprobe(struct kprobe *p) out: mutex_unlock(&kprobe_mutex); +#if IS_ENABLED(CONFIG_MODULES) if (probed_mod) module_put(probed_mod); +#endif return ret; } @@ -2482,6 +2497,7 @@ int kprobe_add_area_blacklist(unsigned long start, unsigned long end) return 0; } +#if IS_ENABLED(CONFIG_MODULES) /* Remove all symbols in given area from kprobe blacklist */ static void kprobe_remove_area_blacklist(unsigned long start, unsigned long end) { @@ -2499,6 +2515,7 @@ static void kprobe_remove_ksym_blacklist(unsigned long entry) { kprobe_remove_area_blacklist(entry, entry + 1); } +#endif int __weak arch_kprobe_get_kallsym(unsigned int *symnum, unsigned long *value, char *type, char *sym) @@ -2564,6 +2581,7 @@ static int __init populate_kprobe_blacklist(unsigned long *start, return ret ? : arch_populate_kprobe_blacklist(); } +#if IS_ENABLED(CONFIG_MODULES) static void add_module_kprobe_blacklist(struct module *mod) { unsigned long start, end; @@ -2665,6 +2683,7 @@ static struct notifier_block kprobe_module_nb = { .notifier_call = kprobes_module_callback, .priority = 0 }; +#endif /* IS_ENABLED(CONFIG_MODULES) */ void kprobe_free_init_mem(void) { @@ -2724,8 +2743,11 @@ static int __init init_kprobes(void) err = arch_init_kprobes(); if (!err) err = register_die_notifier(&kprobe_exceptions_nb); + +#if IS_ENABLED(CONFIG_MODULES) if (!err) err = register_module_notifier(&kprobe_module_nb); +#endif kprobes_initialized = (err == 0); kprobe_sysctls_init(); diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index c4c6e0e0068b..dd4598f775b9 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -102,6 +102,7 @@ static nokprobe_inline bool trace_kprobe_has_gone(struct trace_kprobe *tk) return kprobe_gone(&tk->rp.kp); } +#if IS_ENABLED(CONFIG_MODULES) static nokprobe_inline bool trace_kprobe_within_module(struct trace_kprobe *tk, struct module *mod) { @@ -129,6 +130,12 @@ static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk) return ret; } +#else +static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk) +{ + return true; +} +#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; } +#if IS_ENABLED(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 +712,7 @@ static struct notifier_block trace_kprobe_module_nb = { .notifier_call = trace_kprobe_module_callback, .priority = 1 /* Invoked after kprobe module callback */ }; +#endif /* IS_ENABLED(CONFIG_MODULES) */ static int count_symbols(void *data, unsigned long unused) { @@ -1897,8 +1906,10 @@ static __init int init_kprobe_trace_early(void) if (ret) return ret; +#if IS_ENABLED(CONFIG_MODULES) if (register_module_notifier(&trace_kprobe_module_nb)) return -EINVAL; +#endif return 0; }