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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 74D1BC33CAF for ; Thu, 16 Jan 2020 16:57:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 46C7721582 for ; Thu, 16 Jan 2020 16:57:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579193856; bh=HfjzakrVtLjTgqpXPzTXGJej62/144SRDCqaI5/iiDg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=IG5ioLCgdwCja/hVOnMEoqVx3nWMlTGwhlLUyMlmorVKxt/Z6iFSBnQprXTwPH4kZ XdyyqfdFWSFPm9fHxVqdFqMWB59rxq1WzzpC/G3FcNQGQRPvKuNnGX0ApPfkrgXPwA zdlkVYCxR4KFCTwGNtlFR9OCDATaJCwMGwplFSKk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732717AbgAPQ5f (ORCPT ); Thu, 16 Jan 2020 11:57:35 -0500 Received: from mail.kernel.org ([198.145.29.99]:40570 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730131AbgAPQzW (ORCPT ); Thu, 16 Jan 2020 11:55:22 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4E9D024656; Thu, 16 Jan 2020 16:55:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579193722; bh=HfjzakrVtLjTgqpXPzTXGJej62/144SRDCqaI5/iiDg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TPVN70wSSX1IXum6a59TngPbPrc+XqatkRamkGe3/kQJvshRad4stHM7buktXzc+K WIeE+ZSxcynx94Oqf8wJv2WZ9JsmWwy/SYd3Jd0C696PMazlT3VNa7ZwkhFQH8RTT4 HQoizE50l7XWX/7k626B0hhvnE5EjecjwJJme0aw= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "Eric W. Biederman" , Tony Luck , Fenghua Yu , linux-ia64@vger.kernel.org, Sasha Levin Subject: [PATCH AUTOSEL 4.19 016/671] signal/ia64: Use the force_sig(SIGSEGV,...) in ia64_rt_sigreturn Date: Thu, 16 Jan 2020 11:44:07 -0500 Message-Id: <20200116165502.8838-16-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200116165502.8838-1-sashal@kernel.org> References: <20200116165502.8838-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Eric W. Biederman" [ Upstream commit b92adb74adde62d9a9780ff2977d63dcb21aeaa6 ] The ia64 handling of failure to return from a signal frame has been trying to set overlapping fields in struct siginfo since 2.3.43. The si_code corresponds to the fields that were stomped (not the field that is actually written), so I can not imagine a piece of userspace code making sense of the signal frame if it looks closely. In practice failure to return from a signal frame is a rare event that almost never happens. Someone using an alternate signal stack to recover and looking in detail is even more rare. So I presume no one has ever noticed and reported this ia64 nonsense. Sort this out by causing ia64 to use force_sig(SIGSEGV) like other architectures. Fixes: 2.3.43 Cc: Tony Luck Cc: Fenghua Yu Cc: linux-ia64@vger.kernel.org Acked-by: Tony Luck Signed-off-by: "Eric W. Biederman" Signed-off-by: Sasha Levin --- arch/ia64/kernel/signal.c | 10 +--------- 1 file changed, 1 insertion(+), 9 deletions(-) diff --git a/arch/ia64/kernel/signal.c b/arch/ia64/kernel/signal.c index 01fc133b2e4c..9a960829a01d 100644 --- a/arch/ia64/kernel/signal.c +++ b/arch/ia64/kernel/signal.c @@ -110,7 +110,6 @@ ia64_rt_sigreturn (struct sigscratch *scr) { extern char ia64_strace_leave_kernel, ia64_leave_kernel; struct sigcontext __user *sc; - struct siginfo si; sigset_t set; long retval; @@ -153,14 +152,7 @@ ia64_rt_sigreturn (struct sigscratch *scr) return retval; give_sigsegv: - clear_siginfo(&si); - si.si_signo = SIGSEGV; - si.si_errno = 0; - si.si_code = SI_KERNEL; - si.si_pid = task_pid_vnr(current); - si.si_uid = from_kuid_munged(current_user_ns(), current_uid()); - si.si_addr = sc; - force_sig_info(SIGSEGV, &si, current); + force_sig(SIGSEGV, current); return retval; } -- 2.20.1