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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_RED,USER_AGENT_GIT autolearn=unavailable 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 B35F5C433ED for ; Mon, 26 Apr 2021 07:47:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 802E860FEF for ; Mon, 26 Apr 2021 07:47:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233454AbhDZHsW (ORCPT ); Mon, 26 Apr 2021 03:48:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:50384 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233613AbhDZHjr (ORCPT ); Mon, 26 Apr 2021 03:39:47 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 87328611C1; Mon, 26 Apr 2021 07:38:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1619422689; bh=lvDTFbO2kjOhNiaJHK/06WRErW0tZZG9MqNptvbm+NM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YG5oLzWw29RwEymG7EQKexDj+I1eC64h91H/7RdTUKYxh6thY7rUqasogbCTcSRKw T4FQ8jpF3LihbLeIfRK/W1xkm0xGsFO8yL7kvLzgFIHSJrdQJOO7Ouxf7s9VBCo2cp g73Uw5x4SR5HlVpXIA9T8S2dPxOxDmkCfiH12pq8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sven Schnelle , Vasily Gorbik , Krzysztof Kozlowski Subject: [PATCH 5.4 01/20] s390/ptrace: return -ENOSYS when invalid syscall is supplied Date: Mon, 26 Apr 2021 09:29:52 +0200 Message-Id: <20210426072816.735738001@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210426072816.686976183@linuxfoundation.org> References: <20210426072816.686976183@linuxfoundation.org> User-Agent: quilt/0.66 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sven Schnelle commit cd29fa798001075a554b978df3a64e6656c25794 upstream. The current code returns the syscall number which an invalid syscall number is supplied and tracing is enabled. This makes the strace testsuite fail. Signed-off-by: Sven Schnelle Signed-off-by: Vasily Gorbik Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1895132 [krzysztof: adjusted the backport around missing ifdef CONFIG_SECCOMP, add Link and Fixes; apparently this should go with the referenced commit] Fixes: 00332c16b160 ("s390/ptrace: pass invalid syscall numbers to tracing") Signed-off-by: Krzysztof Kozlowski Signed-off-by: Greg Kroah-Hartman --- arch/s390/kernel/ptrace.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) --- a/arch/s390/kernel/ptrace.c +++ b/arch/s390/kernel/ptrace.c @@ -867,6 +867,7 @@ long compat_arch_ptrace(struct task_stru asmlinkage long do_syscall_trace_enter(struct pt_regs *regs) { unsigned long mask = -1UL; + long ret = -1; /* * The sysc_tracesys code in entry.S stored the system @@ -878,27 +879,33 @@ asmlinkage long do_syscall_trace_enter(s * Tracing decided this syscall should not happen. Skip * the system call and the system call restart handling. */ - clear_pt_regs_flag(regs, PIF_SYSCALL); - return -1; + goto skip; } /* Do the secure computing check after ptrace. */ if (secure_computing(NULL)) { /* seccomp failures shouldn't expose any additional code. */ - return -1; + goto skip; } if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT))) - trace_sys_enter(regs, regs->gprs[2]); + trace_sys_enter(regs, regs->int_code & 0xffff); if (is_compat_task()) mask = 0xffffffff; - audit_syscall_entry(regs->gprs[2], regs->orig_gpr2 & mask, + audit_syscall_entry(regs->int_code & 0xffff, regs->orig_gpr2 & mask, regs->gprs[3] &mask, regs->gprs[4] &mask, regs->gprs[5] &mask); + if ((signed long)regs->gprs[2] >= NR_syscalls) { + regs->gprs[2] = -ENOSYS; + ret = -ENOSYS; + } return regs->gprs[2]; +skip: + clear_pt_regs_flag(regs, PIF_SYSCALL); + return ret; } asmlinkage void do_syscall_trace_exit(struct pt_regs *regs)