From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4649BC433E0 for ; Wed, 12 Aug 2020 01:36:23 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E7FCC2054F for ; Wed, 12 Aug 2020 01:36:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="k7Qav+a+" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E7FCC2054F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 87C228D0069; Tue, 11 Aug 2020 21:36:22 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 831148D0001; Tue, 11 Aug 2020 21:36:22 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 743638D0069; Tue, 11 Aug 2020 21:36:22 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0199.hostedemail.com [216.40.44.199]) by kanga.kvack.org (Postfix) with ESMTP id 5C97B8D0001 for ; Tue, 11 Aug 2020 21:36:22 -0400 (EDT) Received: from smtpin09.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 21D4A5853 for ; Wed, 12 Aug 2020 01:36:22 +0000 (UTC) X-FDA: 77140201404.09.kite02_2e04ff526fe7 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin09.hostedemail.com (Postfix) with ESMTP id EDCAD180AD806 for ; Wed, 12 Aug 2020 01:36:21 +0000 (UTC) X-HE-Tag: kite02_2e04ff526fe7 X-Filterd-Recvd-Size: 4231 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf24.hostedemail.com (Postfix) with ESMTP for ; Wed, 12 Aug 2020 01:36:21 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 681FC20658; Wed, 12 Aug 2020 01:36:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597196180; bh=8+7bHb/Ors1rycfH9WEQrlC5SDs+nT19hFIT/ByBNzw=; h=Date:From:To:Subject:In-Reply-To:From; b=k7Qav+a+B4Q35QuKW/PqI0GUOKksKjt2lA5xwgnTn/Ns5APsXWsHMCzx7PuY76fT1 RrHpkNXlOrX/vwqCHvuEeztr/xWqGLcKSpSw5cmhyicvXhembLvnmQRP2tkFqCngFh CTffuzPrp6cOCs6caInvgr6ai4ylGpeKm4J0uBSo= Date: Tue, 11 Aug 2020 18:36:20 -0700 From: Andrew Morton To: akpm@linux-foundation.org, linux-mm@kvack.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org, ytht.net@gmail.com Subject: [patch 115/165] coredump: add %f for executable filename Message-ID: <20200812013620.UOn7owBkI%akpm@linux-foundation.org> In-Reply-To: <20200811182949.e12ae9a472e3b5e27e16ad6c@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Rspamd-Queue-Id: EDCAD180AD806 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam01 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Lepton Wu Subject: coredump: add %f for executable filename The document reads "%e" should be "executable filename" while actually it could be changed by things like pr_ctl PR_SET_NAME. People who uses "%e" in core_pattern get surprised when they find out they get thread name instead of executable filename. This is either a bug of document or a bug of code. Since the behavior of "%e" is there for long time, it could bring another surprise for users if we "fix" the code. So we just "fix" the document. And more, for users who really need the "executable filename" in core_pattern, we introduce a new "%f" for the real executable filename. We already have "%E" for executable path in kernel, so just reuse most of its code for the new added "%f" format. Link: http://lkml.kernel.org/r/20200701031432.2978761-1-ytht.net@gmail.com Signed-off-by: Lepton Wu Signed-off-by: Andrew Morton --- Documentation/admin-guide/sysctl/kernel.rst | 3 ++- fs/coredump.c | 17 +++++++++++++---- 2 files changed, 15 insertions(+), 5 deletions(-) --- a/Documentation/admin-guide/sysctl/kernel.rst~coredump-add-%f-for-executable-filename +++ a/Documentation/admin-guide/sysctl/kernel.rst @@ -164,7 +164,8 @@ core_pattern %s signal number %t UNIX time of dump %h hostname - %e executable filename (may be shortened) + %e executable filename (may be shortened, could be changed by prctl etc) + %f executable filename %E executable path %c maximum size of core file by resource limit RLIMIT_CORE % both are dropped --- a/fs/coredump.c~coredump-add-%f-for-executable-filename +++ a/fs/coredump.c @@ -153,10 +153,10 @@ int cn_esc_printf(struct core_name *cn, return ret; } -static int cn_print_exe_file(struct core_name *cn) +static int cn_print_exe_file(struct core_name *cn, bool name_only) { struct file *exe_file; - char *pathbuf, *path; + char *pathbuf, *path, *ptr; int ret; exe_file = get_mm_exe_file(current->mm); @@ -175,6 +175,11 @@ static int cn_print_exe_file(struct core goto free_buf; } + if (name_only) { + ptr = strrchr(path, '/'); + if (ptr) + path = ptr + 1; + } ret = cn_esc_printf(cn, "%s", path); free_buf: @@ -301,12 +306,16 @@ static int format_corename(struct core_n utsname()->nodename); up_read(&uts_sem); break; - /* executable */ + /* executable, could be changed by prctl PR_SET_NAME etc */ case 'e': err = cn_esc_printf(cn, "%s", current->comm); break; + /* file name of executable */ + case 'f': + err = cn_print_exe_file(cn, true); + break; case 'E': - err = cn_print_exe_file(cn); + err = cn_print_exe_file(cn, false); break; /* core limit size */ case 'c': _