From patchwork Thu Feb 13 07:24:34 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Finn Thain X-Patchwork-Id: 13972932 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 aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9509DC0219D for ; Thu, 13 Feb 2025 08:15:19 +0000 (UTC) Received: from fhigh-b1-smtp.messagingengine.com (fhigh-b1-smtp.messagingengine.com [202.12.124.152]) by mx.groups.io with SMTP id smtpd.web11.5855.1739431482790307350 for ; Wed, 12 Feb 2025 23:24:42 -0800 Authentication-Results: mx.groups.io; dkim=pass header.i=@messagingengine.com header.s=fm3 header.b=JLXTCSQT; spf=none, err=SPF record not found (domain: linux-m68k.org, ip: 202.12.124.152, mailfrom: fthain@linux-m68k.org) Received: from phl-compute-02.internal (phl-compute-02.phl.internal [10.202.2.42]) by mailfhigh.stl.internal (Postfix) with ESMTP id B501E25401EB; Thu, 13 Feb 2025 02:24:41 -0500 (EST) Received: from phl-mailfrontend-02 ([10.202.2.163]) by phl-compute-02.internal (MEProxy); Thu, 13 Feb 2025 02:24:41 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:date:date:feedback-id :feedback-id:from:from:in-reply-to:message-id:reply-to:subject :subject:to:to:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s= fm3; t=1739431481; x=1739517881; bh=Kpjd1dlpYPRSKTDwyzlMgPlazmO2 anW6vzHpGHs+Oh4=; b=JLXTCSQTwymWH67p4RTvIiEGC/3eBUBvch9tnwY9BktP 5jlp4C7NM7grf8n3X1THozL9WFdhdcIRrzFTt5wHBjX5QwpCp4F6qVjykw9BX+mu dZMm8GJdcu5g/hxjH9FKZyITWGlVr3v2igptHJtJpAu6YI7S2gCj0oFLghnBAuh7 MHgS65MqbvQa/1+KG796ZtKJl4e0Q5uAaXmY5uFE5NDVpxVN4VeDe8z8OshZtKto X5+fwB5U0UndEVB8WZx3vd2R8RelySUM8kukBR9wnLlLhAY8XlAzMErvoi521KZe 2rMK9Qok+Nyhb8iHOiuW9DMeHNVUGlSxSeWw1/mcTQ== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeefvddrtddtgdegieduiecutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpggftfghnshhusghstghrihgsvgdp uffrtefokffrpgfnqfghnecuuegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivg hnthhsucdlqddutddtmdenucfjughrpeffkffhvfevufestddtjhdttddttdenucfhrhho mhephfhinhhnucfvhhgrihhnuceofhhthhgrihhnsehlihhnuhigqdhmieekkhdrohhrgh eqnecuggftrfgrthhtvghrnheptdfhleduudejjefgvdetfeeijedtfeeukeduteeuffeu veejieevhefgleeuffffnecuffhomhgrihhnpehkvghrnhgvlhdrohhrghdpshhkvghlvg htohhnrdhssgenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhr ohhmpehfthhhrghinheslhhinhhugidqmheikehkrdhorhhgpdhnsggprhgtphhtthhope eipdhmohguvgepshhmthhpohhuthdprhgtphhtthhopehnohgsuhhhihhrohdurdhifigr mhgrthhsuhesthhoshhhihgsrgdrtghordhjphdprhgtphhtthhopehprghvvghlseguvg hngidruggvpdhrtghpthhtohepvggsihgvuggvrhhmseigmhhishhsihhonhdrtghomhdp rhgtphhtthhopehstghhmhhithiimhhitgesghhmrghilhdrtghomhdprhgtphhtthhope gtihhpqdguvghvsehlihhsthhsrdgtihhpqdhprhhojhgvtghtrdhorhhgpdhrtghpthht oheplhhinhhugidqmheikehksehlihhsthhsrdhlihhnuhigqdhmieekkhdrohhrgh X-ME-Proxy: Feedback-ID: i58a146ae:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Thu, 13 Feb 2025 02:24:38 -0500 (EST) Date: Thu, 13 Feb 2025 18:24:34 +1100 Message-ID: <365a4f78cfdfbb5cbccae64e14539742@linux-m68k.org> From: Finn Thain To: Nobuhiro Iwamatsu , Pavel Machek Cc: "Eric W. Biederman" , Michael Schmitz , cip-dev@lists.cip-project.org, linux-m68k@lists.linux-m68k.org Subject: [PATCH 4.19.y-cip] signal/m68k: Use force_sigsegv(SIGSEGV) in fpsp040_die List-Id: X-Webhook-Received: from li982-79.members.linode.com [45.33.32.79] by aws-us-west-2-korg-lkml-1.web.codeaurora.org with HTTPS for ; Thu, 13 Feb 2025 08:15:19 -0000 X-Groupsio-URL: https://lists.cip-project.org/g/cip-dev/message/17826 From: "Eric W. Biederman" [ Upstream commit a3616a3c02722d1edb95acc7fceade242f6553ba ] In the fpsp040 code when copyin or copyout fails call force_sigsegv(SIGSEGV) instead of do_exit(SIGSEGV). This solves a couple of problems. Because do_exit embeds the ptrace stop PTRACE_EVENT_EXIT a complete stack frame needs to be present for that to work correctly. There is always the information needed for a ptrace stop where get_signal is called. So exiting with a signal solves the ptrace issue. Further exiting with a signal ensures that all of the threads in a process are killed not just the thread that malfunctioned. Which avoids confusing userspace. To make force_sigsegv(SIGSEGV) work in fpsp040_die modify the code to save all of the registers and jump to ret_from_exception (which ultimately calls get_signal) after fpsp040_die returns. v2: Updated the branches to use gas's pseudo ops that automatically calculate the best branch instruction to use for the purpose. v1: https://lkml.kernel.org/r/87a6m8kgtx.fsf_-_@disp2133 Link: https://lkml.kernel.org/r/87tukghjfs.fsf_-_@disp2133 Acked-by: Geert Uytterhoeven Signed-off-by: "Eric W. Biederman" [ Pass 'current' to force_sigsegv() as was done prior to v5.3 ] Signed-off-by: Finn Thain --- arch/m68k/fpsp040/skeleton.S | 3 ++- arch/m68k/kernel/traps.c | 2 +- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/m68k/fpsp040/skeleton.S b/arch/m68k/fpsp040/skeleton.S index 31a9c634c81e..081922c72daa 100644 --- a/arch/m68k/fpsp040/skeleton.S +++ b/arch/m68k/fpsp040/skeleton.S @@ -502,7 +502,8 @@ in_ea: .section .fixup,"ax" .even 1: - jbra fpsp040_die + jbsr fpsp040_die + jbra .Lnotkern .section __ex_table,"a" .align 4 diff --git a/arch/m68k/kernel/traps.c b/arch/m68k/kernel/traps.c index 35f706d836c5..c6f18dc5884b 100644 --- a/arch/m68k/kernel/traps.c +++ b/arch/m68k/kernel/traps.c @@ -1155,7 +1155,7 @@ asmlinkage void set_esp0(unsigned long ssp) */ asmlinkage void fpsp040_die(void) { - do_exit(SIGSEGV); + force_sigsegv(SIGSEGV, current); } #ifdef CONFIG_M68KFPU_EMU