Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751929AbdF3OHL (ORCPT ); Fri, 30 Jun 2017 10:07:11 -0400 Received: from mail-pg0-f66.google.com ([74.125.83.66]:33153 "EHLO mail-pg0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751560AbdF3OHK (ORCPT ); Fri, 30 Jun 2017 10:07:10 -0400 From: Wanlong Gao To: jeyu@redhat.com Cc: linux-kernel@vger.kernel.org, gaowanlong@huawei.com, john.wanghui@huawei.com, wencongyang2@huawei.com, guijianfeng@huawei.com, xiexiuqi@huawei.com, Wanlong Gao Subject: [PATCH v2] modpost: abort if module name is too long Date: Fri, 30 Jun 2017 22:07:03 +0800 Message-Id: <20170630140703.21839-1-wanlong.gao@gmail.com> X-Mailer: git-send-email 2.9.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2328 Lines: 82 Module name has a limited length, but currently the build system allows the build finishing even if the module name is too long. CC /root/kprobe_example/abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz.mod.o /root/kprobe_example/abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz.mod.c:9:2: warning: initializer-string for array of chars is too long [enabled by default] .name = KBUILD_MODNAME, ^ but it's merely a warning. This patch adds the check of the module name length in modpost and stops the build properly. Signed-off-by: Wanlong Gao --- scripts/mod/modpost.c | 29 ++++++++++++++++++++++++----- 1 file changed, 24 insertions(+), 5 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 30d752a..cb16985 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -47,6 +47,12 @@ enum export { export_unused_gpl, export_gpl_future, export_unknown }; +/* In kernel, this size is defined in linux/module.h; + * here we use Elf_Addr instead of long for covering cross-compile + */ + +#define MODULE_NAME_LEN (64 - sizeof(Elf_Addr)) + #define PRINTF __attribute__ ((format (printf, 1, 2))) PRINTF void fatal(const char *fmt, ...) @@ -2116,6 +2122,23 @@ static void check_exports(struct module *mod) } } +static int check_modname_len(struct module *mod) +{ + const char *mod_name; + + mod_name = strrchr(mod->name, '/'); + if (mod_name == NULL) + mod_name = mod->name; + else + mod_name++; + if (strlen(mod_name) >= MODULE_NAME_LEN) { + merror("module name is too long [%s.ko]\n", mod->name); + return 1; + } + + return 0; +} + /** * Header for the generated file **/ @@ -2154,11 +2177,6 @@ static void add_staging_flag(struct buffer *b, const char *name) buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n"); } -/* In kernel, this size is defined in linux/module.h; - * here we use Elf_Addr instead of long for covering cross-compile - */ -#define MODULE_NAME_LEN (64 - sizeof(Elf_Addr)) - /** * Record CRCs for unresolved symbols **/ @@ -2489,6 +2507,7 @@ int main(int argc, char **argv) buf.pos = 0; + err |= check_modname_len(mod); add_header(&buf, mod); add_intree_flag(&buf, !external_module); add_staging_flag(&buf, mod->name); -- 2.9.4