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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 67446C433EF for ; Wed, 3 Nov 2021 19:07:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4B8A6610EA for ; Wed, 3 Nov 2021 19:07:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231288AbhKCTKX (ORCPT ); Wed, 3 Nov 2021 15:10:23 -0400 Received: from out03.mta.xmission.com ([166.70.13.233]:60278 "EHLO out03.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229697AbhKCTKV (ORCPT ); Wed, 3 Nov 2021 15:10:21 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]:47506) by out03.mta.xmission.com with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1miLbs-000ch0-4k; Wed, 03 Nov 2021 13:07:44 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95]:53986 helo=email.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1miLbq-002G6s-PB; Wed, 03 Nov 2021 13:07:43 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Linus Torvalds Cc: , Oleg Nesterov , Al Viro , Kees Cook , Date: Wed, 03 Nov 2021 14:07:36 -0500 Message-ID: <878ry512iv.fsf@disp2133> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-XM-SPF: eid=1miLbq-002G6s-PB;;;mid=<878ry512iv.fsf@disp2133>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX1/L36RxVZc3PY5oCLUJ61fTl/cpMvTH2qc= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com Subject: [GIT PULL] per signal_struct coredumps X-SA-Exim-Version: 4.2.1 (built Sat, 08 Feb 2020 21:53:50 +0000) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Linus, Please pull the per_signal_struct_coredumps-for-v5.16 branch from the git tree: git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git per_signal_struct_coredumps-for-v5.16 HEAD: 3f66f86bfed33dee2e9c1d0e14486915bb0750b0 per signal_struct coredumps Current coredumps are mixed up with the exit code, the signal handling code, and the ptrace code making coredumps much more complicated than necessary and difficult to follow. This series of changes starts with ptrace_stop and cleans it up, making it easier to follow what is happening in ptrace_stop. Then cleans up the exec interactions with coredumps. Then cleans up the coredump interactions with exit. Then the coredump interactions with the signal handling code is cleaned up. The first and last changes are bug fixes for minor bugs. I believe the fact that vfork followed by execve can kill the process the called vfork if exec fails is sufficient justification to change the userspace visible behavior. In previous discussions some of these changes were organized differently and individually appeared to make the code base worse. As currently written I believe they all stand on their own as cleanups and bug fixes. Which means that even if the worst should happen and the last change needs to be reverted for some unimaginable reason, the code base will still be improved. If the worst does not happen there are a more cleanups that can be made. Signals that generate coredumps can easily become eligible for short circuit delivery in complete_signal. The entire rendezvous for generating a coredump can move into get_signal. The function force_sig_info_to_task be written in a way that does not modify the signal handling state of the target task (because coredumps are eligible for short circuit delivery). Many of these future cleanups can be done another way but nothing so cleanly as if coredumps become per signal_struct. Eric W. Biederman (7): signal: Remove the bogus sigkill_pending in ptrace_stop ptrace: Remove the unnecessary arguments from arch_ptrace_stop exec: Check for a pending fatal signal instead of core_state exit: Factor coredump_exit_mm out of exit_mm coredump: Don't perform any cleanups before dumping core coredump: Limit coredumps to a single thread group per signal_struct coredumps arch/ia64/include/asm/ptrace.h | 4 +- arch/sparc/include/asm/ptrace.h | 8 ++-- fs/binfmt_elf.c | 4 +- fs/binfmt_elf_fdpic.c | 2 +- fs/coredump.c | 88 ++++++----------------------------------- fs/exec.c | 14 +++---- fs/proc/array.c | 6 +-- include/linux/mm_types.h | 13 ------ include/linux/ptrace.h | 22 +++++------ include/linux/sched.h | 1 + include/linux/sched/signal.h | 13 ++++++ kernel/exit.c | 76 +++++++++++++++++++---------------- kernel/fork.c | 4 +- kernel/signal.c | 49 ++++------------------- mm/debug.c | 4 +- mm/oom_kill.c | 6 +-- 16 files changed, 106 insertions(+), 208 deletions(-) Link: https://lkml.kernel.org/r/87v92qx2c6.fsf@disp2133 Signed-off-by: "Eric W. Biederman" Eric