From patchwork Tue Aug 13 12:17:01 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?q?Matthias_M=C3=A4nnich?= X-Patchwork-Id: 11092045 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A464814D5 for ; Tue, 13 Aug 2019 12:19:49 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 94F8628429 for ; Tue, 13 Aug 2019 12:19:49 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 87729284AA; Tue, 13 Aug 2019 12:19:49 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.5 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, USER_IN_DEF_DKIM_WL autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id ECEE328438 for ; Tue, 13 Aug 2019 12:19:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727993AbfHMMTY (ORCPT ); Tue, 13 Aug 2019 08:19:24 -0400 Received: from mail-yw1-f74.google.com ([209.85.161.74]:42995 "EHLO mail-yw1-f74.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727972AbfHMMTX (ORCPT ); Tue, 13 Aug 2019 08:19:23 -0400 Received: by mail-yw1-f74.google.com with SMTP id p2so3381798ywp.9 for ; Tue, 13 Aug 2019 05:19:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=HpxTJ+Mr7aDpwqzbuLs57072o/YccUWCimGiPU7phnE=; b=OuyQ94/nt804hp61UoeUchuI/aqRMg28mHd7oABDF2Cyczt1mZCejkwL7lB+sBjdRh JAn6sAoGvscDOqO8dVL8RzgR1whtoXFnsyxj4TWmnyGy7w4SZ+Jc4F1/kCO6Z382X8+7 Fant1MoHm+8dS+xoQd0/s+JhPToCNP72HL2M/fhmJ53vRsjhSbJKhBWKnHIhAmc7/jS+ vrJsSITVktiKz1s2yI8r8cYq1PIXBhqT5oHzgqd96ySMvbKwXwUsdfKclqnTAJlS7IcT 02OLaAfbdo54ZbNBZ6/eJ+z2eqPKlHe8LXReE+t6e+0lHZSjRsZwcz/QzIxC8YpUiD+p bDXg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=HpxTJ+Mr7aDpwqzbuLs57072o/YccUWCimGiPU7phnE=; b=UlZemv6RCA5uOoTYaKYvjPu4WopY1K6ndD3DeMuU5dzfrPak6X4egqObnuCQqCA2ul 9TwmkwKSp/wMsEnMpnf1hDkaRKljLWQ0GuwSgFRgSkrLAuXn1FXEqFkun9ogLXMnVR8W E6Ee3PNh+NfByjNf/NtRJpVNCSf0hx0woNZmEkpi+r7yuJVTAaU7Gg3WUHb1Yzt5xO3N 4hO1lP0XWUJ4/4N4Q3iTGTyzlst4gHYe9lounf2bv9XYkKjvEAJ60Gt8EuqDWFBr+tEu et6JIb3DmgJwgbx/EKc+1UWKAoFD9cI26OeNcxH5DAFrhb5ySDbwpd9U9Q40HJ8s7cGQ axMA== X-Gm-Message-State: APjAAAXdeBZCW4JmnGnGFUicBi+xO1jLqlbtFyTiMCE4eZMgSlkHIiul f9EsxG49O6FQ1UW+KuxUQhVHIM7kjLWf4Q== X-Google-Smtp-Source: APXvYqyL7MKtHQIe71quZqFSoY/CnTVLPr3iZJYHCupohaJ0tbBkfxJQEvLSzQWyrQooOYAtOrznKBjVq25+nA== X-Received: by 2002:a81:6a8a:: with SMTP id f132mr27823621ywc.358.1565698761694; Tue, 13 Aug 2019 05:19:21 -0700 (PDT) Date: Tue, 13 Aug 2019 13:17:01 +0100 In-Reply-To: <20190813121733.52480-1-maennich@google.com> Message-Id: <20190813121733.52480-5-maennich@google.com> Mime-Version: 1.0 References: <20180716122125.175792-1-maco@android.com> <20190813121733.52480-1-maennich@google.com> X-Mailer: git-send-email 2.23.0.rc1.153.gdeed80330f-goog Subject: [PATCH v2 04/10] modpost: add support for symbol namespaces From: Matthias Maennich To: linux-kernel@vger.kernel.org, maco@android.com Cc: kernel-team@android.com, maennich@google.com, arnd@arndb.de, geert@linux-m68k.org, gregkh@linuxfoundation.org, hpa@zytor.com, jeyu@kernel.org, joel@joelfernandes.org, kstewart@linuxfoundation.org, linux-arch@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-modules@vger.kernel.org, linux-scsi@vger.kernel.org, linux-usb@vger.kernel.org, lucas.de.marchi@gmail.com, maco@google.com, michal.lkml@markovi.net, mingo@redhat.com, oneukum@suse.com, pombredanne@nexb.com, sam@ravnborg.org, sboyd@codeaurora.org, sspatil@google.com, stern@rowland.harvard.edu, tglx@linutronix.de, usb-storage@lists.one-eyed-alien.net, x86@kernel.org, yamada.masahiro@socionext.com Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Add support for symbols that are exported into namespaces. For that, extract any namespace suffix from the symbol name. In addition, emit a warning whenever a module refers to an exported symbol without explicitly importing the namespace that it is defined in. This patch consistently adds the namespace suffix to symbol names exported into Module.symvers. Example warning emitted by modpost in case of the above violation: WARNING: module ums-usbat uses symbol usb_stor_resume from namespace USB_STORAGE, but does not import it. Co-developed-by: Martijn Coenen Signed-off-by: Martijn Coenen Reviewed-by: Joel Fernandes (Google) Signed-off-by: Matthias Maennich Reviewed-by: Greg Kroah-Hartman --- scripts/mod/modpost.c | 91 +++++++++++++++++++++++++++++++++++++------ scripts/mod/modpost.h | 7 ++++ 2 files changed, 87 insertions(+), 11 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index f277e116e0eb..538bb24ffee3 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -164,6 +164,7 @@ struct symbol { struct module *module; unsigned int crc; int crc_valid; + const char *namespace; unsigned int weak:1; unsigned int vmlinux:1; /* 1 if symbol is defined in vmlinux */ unsigned int kernel:1; /* 1 if symbol is from kernel @@ -233,6 +234,37 @@ static struct symbol *find_symbol(const char *name) return NULL; } +static bool contains_namespace(struct namespace_list *list, + const char *namespace) +{ + struct namespace_list *ns_entry; + + for (ns_entry = list; ns_entry != NULL; ns_entry = ns_entry->next) + if (strcmp(ns_entry->namespace, namespace) == 0) + return true; + + return false; +} + +static void add_namespace(struct namespace_list **list, const char *namespace) +{ + struct namespace_list *ns_entry; + + if (!contains_namespace(*list, namespace)) { + ns_entry = NOFAIL(malloc(sizeof(struct namespace_list) + + strlen(namespace) + 1)); + strcpy(ns_entry->namespace, namespace); + ns_entry->next = *list; + *list = ns_entry; + } +} + +static bool module_imports_namespace(struct module *module, + const char *namespace) +{ + return contains_namespace(module->imported_namespaces, namespace); +} + static const struct { const char *str; enum export export; @@ -312,6 +344,22 @@ static enum export export_from_sec(struct elf_info *elf, unsigned int sec) return export_unknown; } +static const char *sym_extract_namespace(const char **symname) +{ + size_t n; + char *dupsymname; + + n = strcspn(*symname, "."); + if (n < strlen(*symname) - 1) { + dupsymname = NOFAIL(strdup(*symname)); + dupsymname[n] = '\0'; + *symname = dupsymname; + return dupsymname + n + 1; + } + + return NULL; +} + /** * Add an exported symbol - it may have already been added without a * CRC, in this case just update the CRC @@ -319,16 +367,18 @@ static enum export export_from_sec(struct elf_info *elf, unsigned int sec) static struct symbol *sym_add_exported(const char *name, struct module *mod, enum export export) { - struct symbol *s = find_symbol(name); + const char *symbol_name = name; + const char *namespace = sym_extract_namespace(&symbol_name); + struct symbol *s = find_symbol(symbol_name); if (!s) { - s = new_symbol(name, mod, export); + s = new_symbol(symbol_name, mod, export); + s->namespace = namespace; } else { if (!s->preloaded) { - warn("%s: '%s' exported twice. Previous export " - "was in %s%s\n", mod->name, name, - s->module->name, - is_vmlinux(s->module->name) ?"":".ko"); + warn("%s: '%s' exported twice. Previous export was in %s%s\n", + mod->name, symbol_name, s->module->name, + is_vmlinux(s->module->name) ? "" : ".ko"); } else { /* In case Module.symvers was out of date */ s->module = mod; @@ -1943,6 +1993,7 @@ static void read_symbols(const char *modname) const char *symname; char *version; char *license; + char *namespace; struct module *mod; struct elf_info info = { }; Elf_Sym *sym; @@ -1974,6 +2025,12 @@ static void read_symbols(const char *modname) license = get_next_modinfo(&info, "license", license); } + namespace = get_modinfo(&info, "import_ns"); + while (namespace) { + add_namespace(&mod->imported_namespaces, namespace); + namespace = get_next_modinfo(&info, "import_ns", namespace); + } + for (sym = info.symtab_start; sym < info.symtab_stop; sym++) { symname = remove_dot(info.strtab + sym->st_name); @@ -2118,6 +2175,13 @@ static int check_exports(struct module *mod) basename++; else basename = mod->name; + + if (exp->namespace && + !module_imports_namespace(mod, exp->namespace)) { + warn("module %s uses symbol %s from namespace %s, but does not import it.\n", + basename, exp->name, exp->namespace); + } + if (!mod->gpl_compatible) check_for_gpl_usage(exp->export, basename, exp->name); check_for_unused(exp->export, basename, exp->name); @@ -2395,16 +2459,21 @@ static void write_dump(const char *fname) { struct buffer buf = { }; struct symbol *symbol; + const char *namespace; int n; for (n = 0; n < SYMBOL_HASH_SIZE ; n++) { symbol = symbolhash[n]; while (symbol) { - if (dump_sym(symbol)) - buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n", - symbol->crc, symbol->name, - symbol->module->name, - export_str(symbol->export)); + if (dump_sym(symbol)) { + namespace = symbol->namespace; + buf_printf(&buf, "0x%08x\t%s%s%s\t%s\t%s\n", + symbol->crc, symbol->name, + namespace ? "." : "", + namespace ? namespace : "", + symbol->module->name, + export_str(symbol->export)); + } symbol = symbol->next; } } diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h index 8453d6ac2f77..9626bf3e7424 100644 --- a/scripts/mod/modpost.h +++ b/scripts/mod/modpost.h @@ -109,6 +109,11 @@ buf_printf(struct buffer *buf, const char *fmt, ...); void buf_write(struct buffer *buf, const char *s, int len); +struct namespace_list { + struct namespace_list *next; + char namespace[0]; +}; + struct module { struct module *next; const char *name; @@ -121,6 +126,8 @@ struct module { struct buffer dev_table_buf; char srcversion[25]; int is_dot_o; + // Actual imported namespaces + struct namespace_list *imported_namespaces; }; struct elf_info {