Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751190AbeAAGmO (ORCPT + 1 other); Mon, 1 Jan 2018 01:42:14 -0500 Received: from conssluserg-06.nifty.com ([210.131.2.91]:38290 "EHLO conssluserg-06.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750992AbeAAGmM (ORCPT ); Mon, 1 Jan 2018 01:42:12 -0500 DKIM-Filter: OpenDKIM Filter v2.10.3 conssluserg-06.nifty.com w016fqCQ024754 X-Nifty-SrcIP: [209.85.217.178] X-Google-Smtp-Source: ACJfBovtejIfMNHUHNOxh2a8iunRtdq9sK0qjaD9endQ4iCKrJV+ddrNKdF+KkXPDVkYqiU4uucMpkrFTwwTlFqECaQ= MIME-Version: 1.0 In-Reply-To: <20171231154548.GA27372@osadl.at> References: <1513801623-19069-1-git-send-email-lukas.bulwahn@gmail.com> <1513883429-9527-1-git-send-email-lukas.bulwahn@gmail.com> <20171231154548.GA27372@osadl.at> From: Masahiro Yamada Date: Mon, 1 Jan 2018 15:41:10 +0900 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v2] fixdep: exit with error code in error branches of do_config_file() To: Nicholas Mc Guire Cc: Lukas Bulwahn , Linux Kbuild mailing list , sil2review@lists.osadl.org, Michal Marek , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: 2018-01-01 0:45 GMT+09:00 Nicholas Mc Guire : > On Sun, Dec 31, 2017 at 01:51:33AM +0900, Masahiro Yamada wrote: >> 2017-12-22 4:10 GMT+09:00 Lukas Bulwahn : >> > do_config_file() should exit with an error code, and not return if it fails >> > as then the error in do_config_file() would go unnoticed in the current >> > code and allow the build to continue. The exit with error code will make >> > the build fail in those very exceptional cases. If this occurs, this >> > actually indicates a deeper problem in the execution of the kernel build >> > process. >> > >> > Now, that the function exists, we do not explicitly free memory and close >> > the file handlers in do_config_file(), as this is covered by exit(). >> > >> > This issue in the fixdep script was introduced with its initial >> > implementation back in 2002 by the original author Kai Germaschewski with >> > this commit 04bd72170653 ("kbuild: Make dependencies at compile time"). >> >> "04bd72170653" is just confusing. >> >> If you really want to mention this hash, >> please clearly say it is in the history repository >> outside of this. >> >> >> > This issue was identified during the review of a previous patch that >> > intended to address a memory leak detected by a static analysis tool. >> > >> > Link: https://lkml.org/lkml/2017/12/14/736 >> > >> > Fixes: 04bd72170653 ("kbuild: Make dependencies at compile time") >> >> Please drop this pointless Fixes tag >> because that commit is not reachable from this patch. >> >> >> >> > Suggested-by: Nicholas Mc Guire >> > Suggested-by: Masahiro Yamada >> > Signed-off-by: Lukas Bulwahn >> > --- >> > compile tested on top of next-20171220 with clang and gcc >> > Change in v2: >> > - no code change; only include proper Fixes tag and explain it >> > >> > scripts/basic/fixdep.c | 11 +++++------ >> > 1 file changed, 5 insertions(+), 6 deletions(-) >> > >> > diff --git a/scripts/basic/fixdep.c b/scripts/basic/fixdep.c >> > index bbf62cb..4274610 100644 >> > --- a/scripts/basic/fixdep.c >> > +++ b/scripts/basic/fixdep.c >> > @@ -284,19 +284,18 @@ static void do_config_file(const char *filename) >> > exit(2); >> > } >> > if (st.st_size == 0) { >> > - close(fd); >> > - return; >> > + fprintf(stderr, "fixdep: error empty file config file: "); >> > + perror(filename); >> > + exit(2); >> > } >> >> No. This is correct as-is. >> >> do_config_file() does not parse .cmd files >> but parse source files (.c .h .S etc.) >> > > What case for a legitimately empty source file would there be ? > the files being checked are assumed to be mandatory for the > given configuration right ? if so how can a configuration depend > on an empty file ? would that not point to a config problem and > rather be fixed there ? or am I misunderstanding this here ? > >> Having an empty source file is rare, but possible. >> > > putting a printf in the empty case handling and running a set of > randconfigs did not reveal such an event (10 runs). Remove the comment line in scripts/mod/empty.c > thx! > hofrat > >> >> >> >> >> >> > map = malloc(st.st_size + 1); >> > if (!map) { >> > perror("fixdep: malloc"); >> > - close(fd); >> > - return; >> > + exit(2); >> > } >> > if (read(fd, map, st.st_size) != st.st_size) { >> > perror("fixdep: read"); >> > - close(fd); >> > - return; >> > + exit(2); >> > } >> > map[st.st_size] = '\0'; >> > close(fd); >> > -- >> > 2.7.4 >> > >> >> These two changes are OK. >> >> >> >> -- >> Best Regards >> Masahiro Yamada > -- > To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Best Regards Masahiro Yamada