From patchwork Sun Jan 30 21:32:11 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aaron Tomlin X-Patchwork-Id: 12730177 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id ECE30C433EF for ; Sun, 30 Jan 2022 21:33:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356468AbiA3Vdg (ORCPT ); Sun, 30 Jan 2022 16:33:36 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:35310 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1356475AbiA3Vcd (ORCPT ); Sun, 30 Jan 2022 16:32:33 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1643578353; 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=al/jYJxi8UyrW4mEBmLd1lyNjLUXPonhqIBGpMy93Lw=; b=ZHgSOhdfic7wHsAQ2xR+1KSFavYbZV6igYvbZYdjn0p5mo7AVdQ+fC9N1Xl3BGhz3/CP9k pnssGgvZT1a1M8qYyDzzNfVA7tbK9XTe2pZhruZbY8YdjUmLDF0J1drsryhw1ftxSlAnc1 PsF7hD3xmuCjzwhJAy+fMx6C8qzuavk= Received: from mail-wm1-f72.google.com (mail-wm1-f72.google.com [209.85.128.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-101-L_dbbdW7OZ-DyRNZM_Xt_g-1; Sun, 30 Jan 2022 16:32:31 -0500 X-MC-Unique: L_dbbdW7OZ-DyRNZM_Xt_g-1 Received: by mail-wm1-f72.google.com with SMTP id d140-20020a1c1d92000000b0034edefd55caso9338992wmd.4 for ; Sun, 30 Jan 2022 13:32:31 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=al/jYJxi8UyrW4mEBmLd1lyNjLUXPonhqIBGpMy93Lw=; b=A5ZXne4dOJfTGMndnlJQGD1Z2IvXEPfiD98fqSZ4jlKiUMxRR3gnUzl1hci10dt0+n ILKrmXYFTAAGxHd11OEgYSViHCs1nsvaONqPPzT5Z5G5GXMVyZsRLVFdEV0O/iix2Wqj FsHabvo58tRjL91vQ+tBsFW5iovvczW8PI2MhlwlMISbZE2lpWYWksbtcmBKrikbWvIh YUCyGWdEmdqoSX2NUF/ercnLCiLndRg/kDCpIZ66OeNLV448jZvp6QyQHW0o1+J3MmKD lnokk4k20mmX9ez6LYpu+AkPmPavWnblZlVcXXV68L7XFkoJPYwXj4LNK6gT30mTDAS/ 3xOw== X-Gm-Message-State: AOAM533nu9fmFNk/sumJKaRS2xzXgDRb1df8Yld4B/56q016vkLOF6JW XfZdUNQsLnC+CXDIKqJ552+QfgIhD1nVI2e6+Y4hz9Q1zZ/N4cJTECAotmCFqvg07Y+PHBb7MDp MlP1j051vTTaYbsu0slBFetYD X-Received: by 2002:a5d:4f08:: with SMTP id c8mr15236685wru.710.1643578350371; Sun, 30 Jan 2022 13:32:30 -0800 (PST) X-Google-Smtp-Source: ABdhPJwU0FmzRtmHVNoE9ddKC8OpTlksQWrPP2QV0qL/lMtoozpTHWYbo2UIdJxcVd9J5gyWDMSz8w== X-Received: by 2002:a5d:4f08:: with SMTP id c8mr15236666wru.710.1643578350053; Sun, 30 Jan 2022 13:32:30 -0800 (PST) Received: from localhost (cpc111743-lutn13-2-0-cust979.9-3.cable.virginm.net. [82.17.115.212]) by smtp.gmail.com with ESMTPSA id 5sm11630584wrb.113.2022.01.30.13.32.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 30 Jan 2022 13:32:29 -0800 (PST) From: Aaron Tomlin To: mcgrof@kernel.org Cc: cl@linux.com, pmladek@suse.com, mbenes@suse.cz, akpm@linux-foundation.org, jeyu@kernel.org, linux-kernel@vger.kernel.org, linux-modules@vger.kernel.org, live-patching@vger.kernel.org, atomlin@atomlin.com, ghalat@redhat.com, allen.lkml@gmail.com, void@manifault.com, joe@perches.com Subject: [RFC PATCH v4 10/13] module: Move procfs support into a separate file Date: Sun, 30 Jan 2022 21:32:11 +0000 Message-Id: <20220130213214.1042497-11-atomlin@redhat.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220130213214.1042497-1-atomlin@redhat.com> References: <20220130213214.1042497-1-atomlin@redhat.com> MIME-Version: 1.0 Precedence: bulk List-ID: No functional change. This patch migrates code that allows one to generate a list of loaded/or linked modules via /proc when procfs support is enabled into kernel/module/procfs.c. Signed-off-by: Aaron Tomlin --- kernel/module/Makefile | 1 + kernel/module/internal.h | 1 + kernel/module/main.c | 131 +----------------------------------- kernel/module/procfs.c | 142 +++++++++++++++++++++++++++++++++++++++ 4 files changed, 145 insertions(+), 130 deletions(-) create mode 100644 kernel/module/procfs.c diff --git a/kernel/module/Makefile b/kernel/module/Makefile index 906f83e1931b..812f11ad090e 100644 --- a/kernel/module/Makefile +++ b/kernel/module/Makefile @@ -14,4 +14,5 @@ obj-$(CONFIG_ARCH_HAS_STRICT_MODULE_RWX) += arch_strict_rwx.o obj-$(CONFIG_STRICT_MODULE_RWX) += strict_rwx.o obj-$(CONFIG_DEBUG_KMEMLEAK) += debug_kmemleak.o obj-$(CONFIG_KALLSYMS) += kallsyms.o +obj-$(CONFIG_PROC_FS) += procfs.o endif diff --git a/kernel/module/internal.h b/kernel/module/internal.h index 866fce7c1a33..09484a9382bc 100644 --- a/kernel/module/internal.h +++ b/kernel/module/internal.h @@ -62,6 +62,7 @@ extern unsigned long kernel_symbol_value(const struct kernel_symbol *sym); extern int cmp_name(const void *name, const void *sym); extern long get_offset(struct module *mod, unsigned int *size, Elf_Shdr *sechdr, unsigned int section); +extern char *module_flags(struct module *mod, char *buf); #ifdef CONFIG_LIVEPATCH extern int copy_module_elf(struct module *mod, struct load_info *info); diff --git a/kernel/module/main.c b/kernel/module/main.c index 363a54298f7e..1c20393ab76d 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -21,7 +21,6 @@ #include #include #include -#include #include #include #include @@ -810,31 +809,6 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user, return ret; } -static inline void print_unload_info(struct seq_file *m, struct module *mod) -{ - struct module_use *use; - int printed_something = 0; - - seq_printf(m, " %i ", module_refcount(mod)); - - /* - * Always include a trailing , so userspace can differentiate - * between this and the old multi-field proc format. - */ - list_for_each_entry(use, &mod->source_list, source_list) { - printed_something = 1; - seq_printf(m, "%s,", use->source->name); - } - - if (mod->init != NULL && mod->exit == NULL) { - printed_something = 1; - seq_puts(m, "[permanent],"); - } - - if (!printed_something) - seq_puts(m, "-"); -} - void __symbol_put(const char *symbol) { struct find_symbol_arg fsa = { @@ -924,12 +898,6 @@ void module_put(struct module *module) EXPORT_SYMBOL(module_put); #else /* !CONFIG_MODULE_UNLOAD */ -static inline void print_unload_info(struct seq_file *m, struct module *mod) -{ - /* We don't know the usage count, or what modules are using. */ - seq_puts(m, " - -"); -} - static inline void module_unload_free(struct module *mod) { } @@ -3576,7 +3544,7 @@ static void cfi_cleanup(struct module *mod) } /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */ -static char *module_flags(struct module *mod, char *buf) +char *module_flags(struct module *mod, char *buf) { int bx = 0; @@ -3599,103 +3567,6 @@ static char *module_flags(struct module *mod, char *buf) return buf; } -#ifdef CONFIG_PROC_FS -/* Called by the /proc file system to return a list of modules. */ -static void *m_start(struct seq_file *m, loff_t *pos) -{ - mutex_lock(&module_mutex); - return seq_list_start(&modules, *pos); -} - -static void *m_next(struct seq_file *m, void *p, loff_t *pos) -{ - return seq_list_next(p, &modules, pos); -} - -static void m_stop(struct seq_file *m, void *p) -{ - mutex_unlock(&module_mutex); -} - -static int m_show(struct seq_file *m, void *p) -{ - struct module *mod = list_entry(p, struct module, list); - char buf[MODULE_FLAGS_BUF_SIZE]; - void *value; - - /* We always ignore unformed modules. */ - if (mod->state == MODULE_STATE_UNFORMED) - return 0; - - seq_printf(m, "%s %u", - mod->name, mod->init_layout.size + mod->core_layout.size); - print_unload_info(m, mod); - - /* Informative for users. */ - seq_printf(m, " %s", - mod->state == MODULE_STATE_GOING ? "Unloading" : - mod->state == MODULE_STATE_COMING ? "Loading" : - "Live"); - /* Used by oprofile and other similar tools. */ - value = m->private ? NULL : mod->core_layout.base; - seq_printf(m, " 0x%px", value); - - /* Taints info */ - if (mod->taints) - seq_printf(m, " %s", module_flags(mod, buf)); - - seq_puts(m, "\n"); - return 0; -} - -/* - * Format: modulename size refcount deps address - * - * Where refcount is a number or -, and deps is a comma-separated list - * of depends or -. - */ -static const struct seq_operations modules_op = { - .start = m_start, - .next = m_next, - .stop = m_stop, - .show = m_show -}; - -/* - * This also sets the "private" pointer to non-NULL if the - * kernel pointers should be hidden (so you can just test - * "m->private" to see if you should keep the values private). - * - * We use the same logic as for /proc/kallsyms. - */ -static int modules_open(struct inode *inode, struct file *file) -{ - int err = seq_open(file, &modules_op); - - if (!err) { - struct seq_file *m = file->private_data; - m->private = kallsyms_show_value(file->f_cred) ? NULL : (void *)8ul; - } - - return err; -} - -static const struct proc_ops modules_proc_ops = { - .proc_flags = PROC_ENTRY_PERMANENT, - .proc_open = modules_open, - .proc_read = seq_read, - .proc_lseek = seq_lseek, - .proc_release = seq_release, -}; - -static int __init proc_modules_init(void) -{ - proc_create("modules", 0, NULL, &modules_proc_ops); - return 0; -} -module_init(proc_modules_init); -#endif - /* Given an address, look for it in the module exception tables. */ const struct exception_table_entry *search_module_extables(unsigned long addr) { diff --git a/kernel/module/procfs.c b/kernel/module/procfs.c new file mode 100644 index 000000000000..d706a798b52e --- /dev/null +++ b/kernel/module/procfs.c @@ -0,0 +1,142 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Module proc support + * + * Copyright (C) 2008 Alexey Dobriyan + */ + +#include +#include +#include +#include +#include +#include "internal.h" + +#ifdef CONFIG_MODULE_UNLOAD +static inline void print_unload_info(struct seq_file *m, struct module *mod) +{ + struct module_use *use; + int printed_something = 0; + + seq_printf(m, " %i ", module_refcount(mod)); + + /* + * Always include a trailing , so userspace can differentiate + * between this and the old multi-field proc format. + */ + list_for_each_entry(use, &mod->source_list, source_list) { + printed_something = 1; + seq_printf(m, "%s,", use->source->name); + } + + if (mod->init != NULL && mod->exit == NULL) { + printed_something = 1; + seq_puts(m, "[permanent],"); + } + + if (!printed_something) + seq_puts(m, "-"); +} +#else /* !CONFIG_MODULE_UNLOAD */ +static inline void print_unload_info(struct seq_file *m, struct module *mod) +{ + /* We don't know the usage count, or what modules are using. */ + seq_puts(m, " - -"); +} +#endif /* CONFIG_MODULE_UNLOAD */ + +/* Called by the /proc file system to return a list of modules. */ +static void *m_start(struct seq_file *m, loff_t *pos) +{ + mutex_lock(&module_mutex); + return seq_list_start(&modules, *pos); +} + +static void *m_next(struct seq_file *m, void *p, loff_t *pos) +{ + return seq_list_next(p, &modules, pos); +} + +static void m_stop(struct seq_file *m, void *p) +{ + mutex_unlock(&module_mutex); +} + +static int m_show(struct seq_file *m, void *p) +{ + struct module *mod = list_entry(p, struct module, list); + char buf[MODULE_FLAGS_BUF_SIZE]; + void *value; + + /* We always ignore unformed modules. */ + if (mod->state == MODULE_STATE_UNFORMED) + return 0; + + seq_printf(m, "%s %u", + mod->name, mod->init_layout.size + mod->core_layout.size); + print_unload_info(m, mod); + + /* Informative for users. */ + seq_printf(m, " %s", + mod->state == MODULE_STATE_GOING ? "Unloading" : + mod->state == MODULE_STATE_COMING ? "Loading" : + "Live"); + /* Used by oprofile and other similar tools. */ + value = m->private ? NULL : mod->core_layout.base; + seq_printf(m, " 0x%px", value); + + /* Taints info */ + if (mod->taints) + seq_printf(m, " %s", module_flags(mod, buf)); + + seq_puts(m, "\n"); + return 0; +} + +/* + * Format: modulename size refcount deps address + * + * Where refcount is a number or -, and deps is a comma-separated list + * of depends or -. + */ +static const struct seq_operations modules_op = { + .start = m_start, + .next = m_next, + .stop = m_stop, + .show = m_show +}; + +/* + * This also sets the "private" pointer to non-NULL if the + * kernel pointers should be hidden (so you can just test + * "m->private" to see if you should keep the values private). + * + * We use the same logic as for /proc/kallsyms. + */ +static int modules_open(struct inode *inode, struct file *file) +{ + int err = seq_open(file, &modules_op); + + if (!err) { + struct seq_file *m = file->private_data; + + m->private = kallsyms_show_value(file->f_cred) ? NULL : (void *)8ul; + } + + return err; +} + +static const struct proc_ops modules_proc_ops = { + .proc_flags = PROC_ENTRY_PERMANENT, + .proc_open = modules_open, + .proc_read = seq_read, + .proc_lseek = seq_lseek, + .proc_release = seq_release, +}; + +static int __init proc_modules_init(void) +{ + proc_create("modules", 0, NULL, &modules_proc_ops); + return 0; +} +module_init(proc_modules_init);